PhD dissertation defense proposal. This presentation details my research work with the Compact Muon Solenoid (CMS) Collaboration of the European Organization for Nuclear Research's (CERN) Large Hadron Collider (LHC). Specifically, my investigations of the behavior the strong nuclear force by studying the production rate of beauty and antibeauty quark pairs are presented, and a comparison with leading theoretical models is shown.
Este documento presenta los diagramas y listas de materiales para construir un vúmetro con LEDs que mide el nivel de salida de un amplificador. El circuito utiliza un chip LM3915 para controlar los LEDs en función de la señal de entrada. Se proporcionan diagramas para versiones mono y estéreo, así como circuitos impresos y máscaras para la fabricación. El objetivo es construir un instrumento de medición que indique el nivel de salida del amplificador de manera estética y funcional.
Ch8 lecture slides Chenming Hu Device for ICChenming Hu
The document discusses bipolar junction transistors (BJTs). It begins by stating that BJTs are still preferred for some high-frequency and analog applications due to their high speed and power output, despite MOS technology eroding their early dominance since 1970. It then provides information on the basic operation and characteristics of BJTs, including definitions of terms like bipolar (referring to both holes and electrons conducting current), collector current, current gain, and how the current gain is affected by factors like emitter doping concentration and bandgap narrowing effects. It also discusses the Ebers-Moll model for describing BJT operation in both the active and saturation regions.
Design procedures of bipolar low noise amplifier at radio frequency using s p...mohamed albanna
This document describes the design procedures for an RF bipolar low noise amplifier using S-parameters. It involves selecting a transistor, determining the DC bias point, checking for stability, and designing the input and output matching networks. The procedures are demonstrated through the design of an amplifier using an Infineon BFP640 transistor. Key steps include choosing the transistor based on specifications, examining its data sheet parameters, simulating the DC transfer characteristics to determine the bias point, and considering biasing for gain and noise performance.
Đề Tiếng Anh 12 cơ bản unit 5 có đáp án - VipLam.NetThùy Linh
This document provides a summary of an article about Atlantic College, an excellent private college in Wales. The college gives students experiences outside the classroom in addition to their studies. Students from ages 16 to 18 come from around the world to study. In the afternoons, students do activities like farm work or environmental work. The text notes that students come from diverse backgrounds and many receive grants due to the high fees. It quotes a student from the Netherlands who says the college teaches understanding between people. In conclusion, the college provides an excellent education through effective methods.
Đề Tiếng Anh 12 cơ bản unit 6 có đáp án - VipLam.NetThùy Linh
This document contains an English proficiency test with multiple choice questions on grammar, vocabulary, and reading comprehension. The reading comprehension section provides a passage about a 16-year-old computer programmer named David Jones who earns a high salary but faces challenges in being treated like an adult by banks due to his age. It discusses his job designing computer games, living situation, and aspirations for continued success in the computer industry.
Ch7 lecture slides Chenming Hu Device for ICChenming Hu
The document discusses technology scaling of MOSFETs used in integrated circuits. Key points include:
1) Feature sizes are reduced by around 30% with each new technology node to improve cost, speed, and power consumption.
2) Scaling challenges include increased subthreshold leakage current and threshold voltage roll-off.
3) Innovations such as high-k dielectrics, metal gates, strained silicon, and retrograde well doping help address these challenges and allow scaling to continue.
4) Variations in manufacturing must also be considered and techniques like multiple threshold voltages and supply voltages are used.
This document discusses the position of the Fermi level in intrinsic and extrinsic semiconductors. It begins by defining the intrinsic Fermi level position in an intrinsic semiconductor. It then describes how the Fermi level shifts in n-type and p-type extrinsic semiconductors due to the introduction of donor and acceptor dopants. Equations are provided for calculating the intrinsic carrier concentration and extrinsic carrier concentrations in n-type and p-type materials.
Este documento presenta los diagramas y listas de materiales para construir un vúmetro con LEDs que mide el nivel de salida de un amplificador. El circuito utiliza un chip LM3915 para controlar los LEDs en función de la señal de entrada. Se proporcionan diagramas para versiones mono y estéreo, así como circuitos impresos y máscaras para la fabricación. El objetivo es construir un instrumento de medición que indique el nivel de salida del amplificador de manera estética y funcional.
Ch8 lecture slides Chenming Hu Device for ICChenming Hu
The document discusses bipolar junction transistors (BJTs). It begins by stating that BJTs are still preferred for some high-frequency and analog applications due to their high speed and power output, despite MOS technology eroding their early dominance since 1970. It then provides information on the basic operation and characteristics of BJTs, including definitions of terms like bipolar (referring to both holes and electrons conducting current), collector current, current gain, and how the current gain is affected by factors like emitter doping concentration and bandgap narrowing effects. It also discusses the Ebers-Moll model for describing BJT operation in both the active and saturation regions.
Design procedures of bipolar low noise amplifier at radio frequency using s p...mohamed albanna
This document describes the design procedures for an RF bipolar low noise amplifier using S-parameters. It involves selecting a transistor, determining the DC bias point, checking for stability, and designing the input and output matching networks. The procedures are demonstrated through the design of an amplifier using an Infineon BFP640 transistor. Key steps include choosing the transistor based on specifications, examining its data sheet parameters, simulating the DC transfer characteristics to determine the bias point, and considering biasing for gain and noise performance.
Đề Tiếng Anh 12 cơ bản unit 5 có đáp án - VipLam.NetThùy Linh
This document provides a summary of an article about Atlantic College, an excellent private college in Wales. The college gives students experiences outside the classroom in addition to their studies. Students from ages 16 to 18 come from around the world to study. In the afternoons, students do activities like farm work or environmental work. The text notes that students come from diverse backgrounds and many receive grants due to the high fees. It quotes a student from the Netherlands who says the college teaches understanding between people. In conclusion, the college provides an excellent education through effective methods.
Đề Tiếng Anh 12 cơ bản unit 6 có đáp án - VipLam.NetThùy Linh
This document contains an English proficiency test with multiple choice questions on grammar, vocabulary, and reading comprehension. The reading comprehension section provides a passage about a 16-year-old computer programmer named David Jones who earns a high salary but faces challenges in being treated like an adult by banks due to his age. It discusses his job designing computer games, living situation, and aspirations for continued success in the computer industry.
Ch7 lecture slides Chenming Hu Device for ICChenming Hu
The document discusses technology scaling of MOSFETs used in integrated circuits. Key points include:
1) Feature sizes are reduced by around 30% with each new technology node to improve cost, speed, and power consumption.
2) Scaling challenges include increased subthreshold leakage current and threshold voltage roll-off.
3) Innovations such as high-k dielectrics, metal gates, strained silicon, and retrograde well doping help address these challenges and allow scaling to continue.
4) Variations in manufacturing must also be considered and techniques like multiple threshold voltages and supply voltages are used.
This document discusses the position of the Fermi level in intrinsic and extrinsic semiconductors. It begins by defining the intrinsic Fermi level position in an intrinsic semiconductor. It then describes how the Fermi level shifts in n-type and p-type extrinsic semiconductors due to the introduction of donor and acceptor dopants. Equations are provided for calculating the intrinsic carrier concentration and extrinsic carrier concentrations in n-type and p-type materials.
IC Design of Power Management Circuits (IV)Claudia Sin
by Wing-Hung Ki
Integrated Power Electronics Laboratory
ECE Dept., HKUST
Clear Water Bay, Hong Kong
www.ee.ust.hk/~eeki
International Symposium on Integrated Circuits
Singapore, Dec. 14, 2009
This document contains several HSPICE examples demonstrating circuit analysis techniques, including:
1) Voltage divider, subcircuit, and calling subcircuit simulations;
2) Switching circuits using transmission line gates;
3) Pulse and triangle wave generator circuits;
4) Dependent source examples using VCCS and CCVS;
5) Ideal transformer and rectifier with filter simulations;
6) Mutual inductor, ideal op-amp, and identifying op-amp parameters;
7) Characteristic curve plotting for diode and maximum power transfer analysis.
1. The document discusses transmission lines and their characteristics including different types of transmission lines, distributed circuit models, transmission line equations, and phasor analysis.
2. It also covers topics such as impedance matching, transmission line parameters, wavelength, wave velocity, and signal propagation on transmission lines.
3. Examples of wavelength and wave velocity for different materials at frequencies of 1 GHz and 10 GHz are provided.
1. The document discusses key concepts in amplifier design using the scattering matrix (S-parameters) model. It defines concepts like transducer power gain, operating power gain, available power gain, and stability circles.
2. Operating power gain and available power gain are represented by circles on the Smith chart known as the operating power gain circle and available power gain circle respectively. These circles define the range of stable input/output impedance values that produce constant gain.
3. Several tests for stability are described, including Rollett's K-factor test and stability circles. Unilateral and bilateral cases are also distinguished, with the unilateral case requiring one port to be matched.
This document discusses traveling waves and scattering parameters for analyzing multi-port networks. It begins by defining traveling waves as voltage and current waves that propagate through transmission lines. It then introduces scattering parameters (S-parameters) which describe the input-output relationship of linear electrical networks with multiple ports. S-parameters are presented as elements of a scattering matrix that relates incoming and outgoing wave amplitudes at each port. Methods for calculating reflection and transmission coefficients from S-parameters are provided for characterizing two-port networks. The analysis is then generalized to n-port networks using scattering matrices. Key parameters like return loss, insertion loss, and available power are defined in terms of S-parameters.
KAN Talks 6: Quantum Physics for kids (By Srinivas)Mango Education
About the presenter:
Srinivas is 10 years old. He is a part of Mango Astronomy Club. He is passionate about physics and astronomy. Enjoys sharing whatever he has learnt in science with his peers.
Đề Tiếng Anh 12 cơ bản unit 2 có đáp án - VipLam.NetThùy Linh
This document contains a practice test on English grammar and vocabulary. It includes 50 multiple choice questions testing understanding of word stress, pronunciation, grammar structures, vocabulary meaning, and sentence structure. It also contains short passages testing reading comprehension skills like identifying main ideas, details, and inferences. The document provides an English skills assessment for non-native English speakers.
This document outlines the dissertation of Naomi M. Mangatu titled "Beyond the Glass Ceiling: A Phenomenological Study of Women Managers in the Kenyan Banking Industry." The study explores the lived experiences of 24 women managers in Kenyan banks to understand factors contributing to or hindering their advancement to CEO positions. It uses a qualitative phenomenological research method and the van Kaam 7-step process for data analysis. The findings reveal that while women have made progress in their careers, few break through the glass ceiling to attain top leadership roles in Kenyan banks due to social pressures, cultural norms, and expectations that suppress women's advancement.
The document summarizes research from a dissertation on microbial contributions to carbon and nutrient cycling across tropical landscapes. It finds that:
1) Soil carbon and nutrients decline rapidly with depth, while microbial biomass and activity also decline but metabolic activity per unit biomass remains similar or increases in deeper soils.
2) Soil organic matter chemistry differs between forest types near the surface but not with soil type, and alkyl carbon may be important for long-term tropical carbon storage.
3) Specific phosphatase enzyme activity is higher in deeper soils, suggesting microbes invest more in phosphorus acquisition under resource-limited conditions.
The dissertation defense presentation summarized Hany SalahEldeen's dissertation research on detecting, modeling, and predicting user temporal intention in social media. The research aimed to estimate the temporal intention of authors when sharing content and readers when accessing content. It also sought to model intention over time, predict how shared resources change over time, and implement models to preserve at-risk social media content and provide smooth temporal navigation of the social web. Key aspects of the research included analyzing loss and persistence of shared URLs over time, measuring existence and disappearance as a function of time, and using social context to find replacements for missing resources.
This document provides an overview of a dissertation that examines the influence of export control policy on the competitiveness of machine tool producing organizations. The study aims to quantitatively examine how export control policies may impact the competitiveness of US machine tool manufacturers. It outlines two research questions that assess the relationship between perceptions of export policy and export sales, and whether export policy determines market participation. The methodology involves a survey and comparison of theoretical and actual market models. Key results found no significant relationship between export policy perceptions and sales, but found differences in market participation between firms with supportive versus non-supportive export policies. Overall conclusions are that export control policies do not impose a competitive obstacle on these organizations.
This document summarizes Ed Turner's dissertation on trust in an organization undergoing change. The study examines the relationship between trusting behaviors of senior leaders at a Colorado telecommunications company and subordinates' perceptions of trust during a period of mergers, downsizings and restructuring. The dissertation committee and informed consent are noted. The problem statement, purpose statement, significance, research questions and methodology are outlined. A correlational study using a trust inventory survey of 357 employees from different levels will determine if trust differs by gender, job level or position in the changing organization.
This document contains the agenda for Shobeir K. S. Mazinani's PhD dissertation oral defense at the School of Molecular Sciences. The defense will take place on November 13th and focus on Mazinani's research using molecular models and descriptors to study electron transport in molecular junctions and electrochemical electron transfer. The document outlines Mazinani's work applying theoretical approaches like the Landauer formula and polarizability calculations to examine conductance in examples like halo-benzenes and hydrogen bonds. It also summarizes Mazinani's studies of a nickel phosphine catalyst for hydrogen production and contributions of ligand geometry to its redox properties.
Example Dissertation Proposal Defense Power Point SlideDr. Vince Bridges
Vincent Bridges will defend his dissertation proposal on examining the effectiveness of medical assistant programs at three Midwestern schools in meeting stakeholder needs. The proposal will cover the problem background, purpose of the study, research questions, and literature review. Bridges will use a qualitative survey methodology to collect data from 20-25 healthcare professionals on their organizations' use of medical assistants and program competencies. The data will be analyzed for themes to provide feedback to the schools on curriculum alignment with industry needs.
Presentation for Dissertation Proposal Defenseandrearoofe
This document provides an overview of Andrea Roofe's dissertation proposal on examining the effect of business cycles on the financial performance of socially responsible investments. The summary includes:
1) The proposal outlines research questions on whether SRI delivers financial value and whether performance varies across economic expansions and contractions.
2) The theoretical framework discusses stakeholder theory, social and financial performance links, and how SRI investor attitudes toward risk may impact performance across economic conditions.
3) The methodology proposes examining SRI index and fund returns against benchmarks in both bull and bear markets using Fama-French and Carhart models with Markov switching regimes.
IC Design of Power Management Circuits (IV)Claudia Sin
by Wing-Hung Ki
Integrated Power Electronics Laboratory
ECE Dept., HKUST
Clear Water Bay, Hong Kong
www.ee.ust.hk/~eeki
International Symposium on Integrated Circuits
Singapore, Dec. 14, 2009
This document contains several HSPICE examples demonstrating circuit analysis techniques, including:
1) Voltage divider, subcircuit, and calling subcircuit simulations;
2) Switching circuits using transmission line gates;
3) Pulse and triangle wave generator circuits;
4) Dependent source examples using VCCS and CCVS;
5) Ideal transformer and rectifier with filter simulations;
6) Mutual inductor, ideal op-amp, and identifying op-amp parameters;
7) Characteristic curve plotting for diode and maximum power transfer analysis.
1. The document discusses transmission lines and their characteristics including different types of transmission lines, distributed circuit models, transmission line equations, and phasor analysis.
2. It also covers topics such as impedance matching, transmission line parameters, wavelength, wave velocity, and signal propagation on transmission lines.
3. Examples of wavelength and wave velocity for different materials at frequencies of 1 GHz and 10 GHz are provided.
1. The document discusses key concepts in amplifier design using the scattering matrix (S-parameters) model. It defines concepts like transducer power gain, operating power gain, available power gain, and stability circles.
2. Operating power gain and available power gain are represented by circles on the Smith chart known as the operating power gain circle and available power gain circle respectively. These circles define the range of stable input/output impedance values that produce constant gain.
3. Several tests for stability are described, including Rollett's K-factor test and stability circles. Unilateral and bilateral cases are also distinguished, with the unilateral case requiring one port to be matched.
This document discusses traveling waves and scattering parameters for analyzing multi-port networks. It begins by defining traveling waves as voltage and current waves that propagate through transmission lines. It then introduces scattering parameters (S-parameters) which describe the input-output relationship of linear electrical networks with multiple ports. S-parameters are presented as elements of a scattering matrix that relates incoming and outgoing wave amplitudes at each port. Methods for calculating reflection and transmission coefficients from S-parameters are provided for characterizing two-port networks. The analysis is then generalized to n-port networks using scattering matrices. Key parameters like return loss, insertion loss, and available power are defined in terms of S-parameters.
KAN Talks 6: Quantum Physics for kids (By Srinivas)Mango Education
About the presenter:
Srinivas is 10 years old. He is a part of Mango Astronomy Club. He is passionate about physics and astronomy. Enjoys sharing whatever he has learnt in science with his peers.
Đề Tiếng Anh 12 cơ bản unit 2 có đáp án - VipLam.NetThùy Linh
This document contains a practice test on English grammar and vocabulary. It includes 50 multiple choice questions testing understanding of word stress, pronunciation, grammar structures, vocabulary meaning, and sentence structure. It also contains short passages testing reading comprehension skills like identifying main ideas, details, and inferences. The document provides an English skills assessment for non-native English speakers.
This document outlines the dissertation of Naomi M. Mangatu titled "Beyond the Glass Ceiling: A Phenomenological Study of Women Managers in the Kenyan Banking Industry." The study explores the lived experiences of 24 women managers in Kenyan banks to understand factors contributing to or hindering their advancement to CEO positions. It uses a qualitative phenomenological research method and the van Kaam 7-step process for data analysis. The findings reveal that while women have made progress in their careers, few break through the glass ceiling to attain top leadership roles in Kenyan banks due to social pressures, cultural norms, and expectations that suppress women's advancement.
The document summarizes research from a dissertation on microbial contributions to carbon and nutrient cycling across tropical landscapes. It finds that:
1) Soil carbon and nutrients decline rapidly with depth, while microbial biomass and activity also decline but metabolic activity per unit biomass remains similar or increases in deeper soils.
2) Soil organic matter chemistry differs between forest types near the surface but not with soil type, and alkyl carbon may be important for long-term tropical carbon storage.
3) Specific phosphatase enzyme activity is higher in deeper soils, suggesting microbes invest more in phosphorus acquisition under resource-limited conditions.
The dissertation defense presentation summarized Hany SalahEldeen's dissertation research on detecting, modeling, and predicting user temporal intention in social media. The research aimed to estimate the temporal intention of authors when sharing content and readers when accessing content. It also sought to model intention over time, predict how shared resources change over time, and implement models to preserve at-risk social media content and provide smooth temporal navigation of the social web. Key aspects of the research included analyzing loss and persistence of shared URLs over time, measuring existence and disappearance as a function of time, and using social context to find replacements for missing resources.
This document provides an overview of a dissertation that examines the influence of export control policy on the competitiveness of machine tool producing organizations. The study aims to quantitatively examine how export control policies may impact the competitiveness of US machine tool manufacturers. It outlines two research questions that assess the relationship between perceptions of export policy and export sales, and whether export policy determines market participation. The methodology involves a survey and comparison of theoretical and actual market models. Key results found no significant relationship between export policy perceptions and sales, but found differences in market participation between firms with supportive versus non-supportive export policies. Overall conclusions are that export control policies do not impose a competitive obstacle on these organizations.
This document summarizes Ed Turner's dissertation on trust in an organization undergoing change. The study examines the relationship between trusting behaviors of senior leaders at a Colorado telecommunications company and subordinates' perceptions of trust during a period of mergers, downsizings and restructuring. The dissertation committee and informed consent are noted. The problem statement, purpose statement, significance, research questions and methodology are outlined. A correlational study using a trust inventory survey of 357 employees from different levels will determine if trust differs by gender, job level or position in the changing organization.
This document contains the agenda for Shobeir K. S. Mazinani's PhD dissertation oral defense at the School of Molecular Sciences. The defense will take place on November 13th and focus on Mazinani's research using molecular models and descriptors to study electron transport in molecular junctions and electrochemical electron transfer. The document outlines Mazinani's work applying theoretical approaches like the Landauer formula and polarizability calculations to examine conductance in examples like halo-benzenes and hydrogen bonds. It also summarizes Mazinani's studies of a nickel phosphine catalyst for hydrogen production and contributions of ligand geometry to its redox properties.
Example Dissertation Proposal Defense Power Point SlideDr. Vince Bridges
Vincent Bridges will defend his dissertation proposal on examining the effectiveness of medical assistant programs at three Midwestern schools in meeting stakeholder needs. The proposal will cover the problem background, purpose of the study, research questions, and literature review. Bridges will use a qualitative survey methodology to collect data from 20-25 healthcare professionals on their organizations' use of medical assistants and program competencies. The data will be analyzed for themes to provide feedback to the schools on curriculum alignment with industry needs.
Presentation for Dissertation Proposal Defenseandrearoofe
This document provides an overview of Andrea Roofe's dissertation proposal on examining the effect of business cycles on the financial performance of socially responsible investments. The summary includes:
1) The proposal outlines research questions on whether SRI delivers financial value and whether performance varies across economic expansions and contractions.
2) The theoretical framework discusses stakeholder theory, social and financial performance links, and how SRI investor attitudes toward risk may impact performance across economic conditions.
3) The methodology proposes examining SRI index and fund returns against benchmarks in both bull and bear markets using Fama-French and Carhart models with Markov switching regimes.
This presentation from Drug Regulations, a nonprofit organization, provides information on sampling procedures from regulatory agencies like the FDA and EMA. It outlines guidelines for sampling components, in-process materials, packaging materials, and finished drug products to ensure quality and batch uniformity according to good manufacturing practices.
This document discusses different types of sampling methods used in qualitative research. It defines key terms like sample, random sampling, and non-probability sampling. It then explains different sampling techniques in more detail, including simple random sampling, systematic random sampling, stratified random sampling, multi-stage cluster sampling, convenience sampling, snowball sampling, quota sampling, accidental sampling, panel sampling, and improving response rates. The document emphasizes that qualitative researchers are more concerned with understanding phenomena in depth than statistical validity or generalizability.
This document summarizes a research project that involves building a toy model of particle collisions using C++ and ROOT. The model simulates collisions by sampling probability distributions measured in real collisions. It generates particles and assigns them properties like momentum and angle. It also models physical processes like jet production and elliptic flow. The goal is to study how properties of particles like jets are affected by a quark-gluon plasma and vice versa. The model allows tuning parameters to learn about collision interactions and switch physics processes on or off.
Ab-initio real-time spectroscopy: application to non-linear opticsClaudio Attaccalite
This document discusses ab-initio real-time spectroscopy and its application to non-linear optics. It begins with an overview of non-linear optics and the polarization response. It then discusses using time-dependent density functional theory to calculate nonlinear optical properties in real-time by solving the time-dependent Schrodinger equation under an external electric field. Examples are given of calculating second and third harmonic generation in materials. The document also discusses approaches to address challenges like treating bulk polarization and including many-body effects.
Search for microscopic black hole signatures at the large hadron colliderSérgio Sacani
The CMS Collaboration at the LHC searched for microscopic black hole signatures using 35 pb-1 of 7 TeV proton-proton collision data. No significant excess beyond standard model expectations was observed in events with high total transverse energy. Limits are set on the minimum black hole mass in the range of 3.5-4.5 TeV for various parameters in the large extra dimensions model. These are the first direct limits on black hole production at a particle collider.
Phonon assisted Luminescence in Hexagonal Boron NitrideElena Cannuccia
Hexagonal boron nitride (h-BN) is an indirect bandgap semiconductor that exhibits phonon-assisted luminescence. Theoretical calculations reproduce the position and intensity of luminescence peaks in h-BN and show they result from indirect excitons being replicated by different phonon modes. While the theory captures single-phonon processes, it cannot fully reproduce overtones involving higher-order phonon sidebands. Recent work has extended the theory to include a finer sampling of exciton and phonon dispersions in order to model multi-phonon scattering processes in the luminescence of h-BN.
35 Charged particle detection at GRAAL - Radiation Effects & Defects in Solid...Cristian Randieri PhD
Charged particle detection at GRAAL - Radiation Effects & Defects in Solids, Taylor & Francis, May June 2009, Vol. 164, N. 5-6, pp. 357-362, ISSN:1042-0150, doi: 10.1080/10420150902811698
di F. Mammoliti, V. Bellini, A. Giusa, C. Randieri, G. Russo, M. L. Sperduto, M. C. Sutera, A. D’Angelo, R. Di Salvo, A. Fantini, D. Franco, D. Moricciani, C. Schaerf, V. Vegna, P. Levi Sandri, G. Mandaglio, G. Giardina (2009)
Abstract
Experimental results on proton and charged pion detection obtained from a study of the γ+n→p+π− reaction are reported in detail. Data have been collected using the tagged and linearly polarized photon beam, impinging on a deuterium target, and the large solid angle apparatus of the GRAAL facility in Grenoble (France). The energy of the charged particles was measured using a BGO calorimeter. A comparison of the experimental data with a GEANT3-based simulation is also presented.
Search for Excited Randall-Sundrum Gravitons from Warped Extra Dimensions wit...Eric Williams
This document describes Eric Williams' thesis defense analyzing data from the ATLAS detector at the LHC to search for excited Randall-Sundrum gravitons decaying to diboson final states. The analysis focuses on the semi-leptonic WW decay channel with one W decaying to a neutrino and the other to two jets. After discussing the Large Hadron Collider, ATLAS detector, and motivations from theories with extra dimensions, the analysis strategy and object selection criteria are outlined. Background processes like W+jets, top, and QCD multijets are estimated, and event yields after preselection are shown to be in agreement between data and simulation. No significant excess is observed.
This document discusses various techniques for crystal structure analysis using diffraction methods, including X-ray diffraction, electron diffraction, and neutron diffraction. It provides background on the essential physics of Bragg diffraction and scattering. Key topics covered include generating X-rays, basic diffractometer setups, powder and thin film diffraction techniques, and applications such as phase identification and structure determination.
The remote sensing working group has investigated methodology for atmospheric remotesensing retrievals, which are mathematical and computational procedures for inferring the state of the atmosphere from remote sensing observations. Satellite data with fine spatial and temporal
resolution present opportunities to combine information across satellite pixels using spatiotemporal statistical modeling. We present examples of this approach at the process level of a hierarchical model, with a nonlinear radiative transfer model incorporated into the likelihood. In
this framework, we assess the impact of various statistical properties on the relative performance of a multi-pixel retrieval strategy versus an operational one-at-a-time approach. The prospect of adopting the approach is illustrated in the context of estimating atmospheric carbon dioxide concentration with data from NASA's Orbiting Carbon Observatory-2 (OCO-2).
The CMS detector at the LHC has a mature and diverse search program for long-lived particles and unconventional signatures. Searches are conducted for displaced jets, muons, vertices, and other signatures using specialized triggers, reconstruction techniques, and analysis categories. Recent results set strong constraints on particle lifetimes from 1 cm to over 100 m, and exclude new parameter space for models of heavy neutral leptons, dark photons, R-parity violating supersymmetry, and more. Ongoing and future searches will further exploit the CMS detector capabilities and refined analysis methods to explore an even wider range of lifetimes and new physics models.
The distribution and_annihilation_of_dark_matter_around_black_holesSérgio Sacani
Uma nova simulação computacional feita pela NASA mostra que as partículas da matéria escura colidindo na extrema gravidade de um buraco negro pode produzir uma luz de raios-gamma forte e potencialmente observável. Detectando essa emissão forneceria aos astrônomos com uma nova ferramenta para entender tanto os buracos negros como a natureza da matéria escura, uma elusiva substância responsável pela maior parte da massa do universo que nem reflete, absorve ou emite luz.
The current ability to test theories of gravity with black hole shadowsSérgio Sacani
Our Galactic Centre, Sagittarius A*, is believed to harbour a
supermassive black hole, as suggested by observations tracking
individual orbiting stars1,2
. Upcoming submillimetre verylong
baseline interferometry images of Sagittarius A* carried
out by the Event Horizon Telescope collaboration (EHTC)3,4
are expected to provide critical evidence for the existence of
this supermassive black hole5,6. We assess our present ability
to use EHTC images to determine whether they correspond
to a Kerr black hole as predicted by Einstein’s theory
of general relativity or to a black hole in alternative theories
of gravity. To this end, we perform general-relativistic magnetohydrodynamical
simulations and use general-relativistic
radiative-transfer calculations to generate synthetic shadow
images of a magnetized accretion flow onto a Kerr black hole.
In addition, we perform these simulations and calculations for
a dilaton black hole, which we take as a representative solution
of an alternative theory of gravity. Adopting the very-long
baseline interferometry configuration from the 2017 EHTC
campaign, we find that it could be extremely difficult to distinguish
between black holes from different theories of gravity,
thus highlighting that great caution is needed when interpreting
black hole images as tests of general relativity.
Rare Kaon Decays: Matching Long and Short Distance Physics in K-> Pi e+ e-Atanu Nath
The document discusses matching long distance and short distance physics in the rare kaon decay process K → πe+e−. It first summarizes the chiral perturbation theory calculation of the form factors for this process at O(p2) and O(p4). It then discusses using the Bardeen-Buras-Gérard matching scheme to extract short distance information and predict the values of the form factor parameters a+ and b+. The matching scheme involves bosonizing quark operators at low energies and interpreting one-loop matrix elements as renormalization group evolution from low to high scales, where matching between long and short distance occurs.
1) The document discusses using quantum probes to indirectly extract information about complex quantum systems like ultracold atomic gases, without directly measuring the system.
2) One method is to use an impurity atom as a qubit probe immersed in a 2D Bose-Einstein condensate. Interactions between the probe and gas induce decoherence on the probe that depends on properties of the gas like dimensionality and phase fluctuations, allowing characterization of the gas.
3) The non-Markovianity of the probe's dynamics, quantified by information flow between the probe and gas, can reveal information about the gas without directly measuring it. Positive information flow indicates non-Markovian dynamics and backflow of information
This document presents a comparative study of the dynamic optical filtering and temperature sensing capabilities of one-dimensional binary and ternary photonic crystals (PHCs). The study finds that:
1) The binary PHC shows four optical bandgaps compared to seven bandgaps in the ternary PHC.
2) For temperatures between 100-700K, both PHCs show improved temperature sensing effectiveness as temperature increases, except for the first bandgap of the binary and the first two bandgaps of the ternary.
3) The binary PHC performs better as a temperature sensor between 840-1100nm, but the ternary PHC outperforms at longer wavelengths.
4)
IOSR Journal of Applied Physics (IOSR-JAP) is an open access international journal that provides rapid publication (within a month) of articles in all areas of physics and its applications. The journal welcomes publications of high quality papers on theoretical developments and practical applications in applied physics. Original research papers, state-of-the-art reviews, and high quality technical notes are invited for publications.
This document discusses nonlinear optics and the dynamical Berry phase. It introduces nonlinear optics and summarizes early experiments. It then discusses how the Berry phase is related to nonlinear optical effects like second harmonic generation (SHG). Computational methods are presented for calculating SHG and other nonlinear optical properties from first principles using time-dependent density functional theory and the dynamical Berry phase. Examples of applying these methods to study SHG in semiconductors are provided.
Collective modes of CFL phase of QCD (QCD@Work 2010)Roberto Anglani
The document discusses collective modes in the color-flavor-locked phase of quantum chromodynamics. It aims to study the low energy effective action for collective modes of the color-flavor-locked phase from a microscopic perspective. In particular, it focuses on determining the Higgs mode and Nambu-Goldstone (phonon) mode of the diquark condensate and their interaction terms. The author develops an effective field theory approach to derive the spectrum and interactions of these collective modes, which could influence properties of compact stars.
Phase-field modeling of crystal nucleation II: Comparison with simulations an...Daniel Wheeler
This document summarizes phase-field modeling of crystal nucleation. It discusses:
1) Homogeneous nucleation models using the phase-field method and their comparison to molecular dynamics simulations and experiments for systems like nickel and Lennard-Jones argon.
2) Applications of the phase-field model to heterogeneous systems like ice-water nucleation.
3) The effects of different double-well and interpolation functions on nucleation behavior in phase-field models.
Phase-field modeling of crystal nucleation II: Comparison with simulations an...PFHub PFHub
This document summarizes phase-field modeling of crystal nucleation. It discusses:
1) Homogeneous nucleation models using the phase-field method and their comparison to molecular dynamics simulations and experiments for systems like nickel and Lennard-Jones argon.
2) Applications of the phase-field model to heterogeneous systems like ice-water nucleation.
3) The effects of different double-well and interpolation functions on nucleation behavior in phase-field models.
Himmetoglu presents research on modeling polarons and their effects in complex oxide materials like YTiO3 using first-principles calculations. Small polarons form when holes become self-trapped due to strong electron-phonon coupling, leading to localized distortions around the hole. Calculations find two stable configurations for a single hole - a small polaron state and a delocalized hole state. The transition between these states is attributed to the 0.6eV onset seen in optical absorption measurements, rather than representing the fundamental band gap. Accounting for small polaron formation reconciles theoretical predictions of band gaps around 2eV with experimental observations.
Leveraging Generative AI to Drive Nonprofit InnovationTechSoup
In this webinar, participants learned how to utilize Generative AI to streamline operations and elevate member engagement. Amazon Web Service experts provided a customer specific use cases and dived into low/no-code tools that are quick and easy to deploy through Amazon Web Service (AWS.)
বাংলাদেশের অর্থনৈতিক সমীক্ষা ২০২৪ [Bangladesh Economic Review 2024 Bangla.pdf] কম্পিউটার , ট্যাব ও স্মার্ট ফোন ভার্সন সহ সম্পূর্ণ বাংলা ই-বুক বা pdf বই " সুচিপত্র ...বুকমার্ক মেনু 🔖 ও হাইপার লিংক মেনু 📝👆 যুক্ত ..
আমাদের সবার জন্য খুব খুব গুরুত্বপূর্ণ একটি বই ..বিসিএস, ব্যাংক, ইউনিভার্সিটি ভর্তি ও যে কোন প্রতিযোগিতা মূলক পরীক্ষার জন্য এর খুব ইম্পরট্যান্ট একটি বিষয় ...তাছাড়া বাংলাদেশের সাম্প্রতিক যে কোন ডাটা বা তথ্য এই বইতে পাবেন ...
তাই একজন নাগরিক হিসাবে এই তথ্য গুলো আপনার জানা প্রয়োজন ...।
বিসিএস ও ব্যাংক এর লিখিত পরীক্ষা ...+এছাড়া মাধ্যমিক ও উচ্চমাধ্যমিকের স্টুডেন্টদের জন্য অনেক কাজে আসবে ...
A workshop hosted by the South African Journal of Science aimed at postgraduate students and early career researchers with little or no experience in writing and publishing journal articles.
How to Fix the Import Error in the Odoo 17Celine George
An import error occurs when a program fails to import a module or library, disrupting its execution. In languages like Python, this issue arises when the specified module cannot be found or accessed, hindering the program's functionality. Resolving import errors is crucial for maintaining smooth software operation and uninterrupted development processes.
Strategies for Effective Upskilling is a presentation by Chinwendu Peace in a Your Skill Boost Masterclass organisation by the Excellence Foundation for South Sudan on 08th and 09th June 2024 from 1 PM to 3 PM on each day.
A review of the growth of the Israel Genealogy Research Association Database Collection for the last 12 months. Our collection is now passed the 3 million mark and still growing. See which archives have contributed the most. See the different types of records we have, and which years have had records added. You can also see what we have for the future.
How to Make a Field Mandatory in Odoo 17Celine George
In Odoo, making a field required can be done through both Python code and XML views. When you set the required attribute to True in Python code, it makes the field required across all views where it's used. Conversely, when you set the required attribute in XML views, it makes the field required only in the context of that particular view.
Walmart Business+ and Spark Good for Nonprofits.pdfTechSoup
"Learn about all the ways Walmart supports nonprofit organizations.
You will hear from Liz Willett, the Head of Nonprofits, and hear about what Walmart is doing to help nonprofits, including Walmart Business and Spark Good. Walmart Business+ is a new offer for nonprofits that offers discounts and also streamlines nonprofits order and expense tracking, saving time and money.
The webinar may also give some examples on how nonprofits can best leverage Walmart Business+.
The event will cover the following::
Walmart Business + (https://business.walmart.com/plus) is a new shopping experience for nonprofits, schools, and local business customers that connects an exclusive online shopping experience to stores. Benefits include free delivery and shipping, a 'Spend Analytics” feature, special discounts, deals and tax-exempt shopping.
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Spark Good (walmart.com/sparkgood) is a charitable platform that enables nonprofits to receive donations directly from customers and associates.
Answers about how you can do more with Walmart!"
Chapter wise All Notes of First year Basic Civil Engineering.pptxDenish Jangid
Chapter wise All Notes of First year Basic Civil Engineering
Syllabus
Chapter-1
Introduction to objective, scope and outcome the subject
Chapter 2
Introduction: Scope and Specialization of Civil Engineering, Role of civil Engineer in Society, Impact of infrastructural development on economy of country.
Chapter 3
Surveying: Object Principles & Types of Surveying; Site Plans, Plans & Maps; Scales & Unit of different Measurements.
Linear Measurements: Instruments used. Linear Measurement by Tape, Ranging out Survey Lines and overcoming Obstructions; Measurements on sloping ground; Tape corrections, conventional symbols. Angular Measurements: Instruments used; Introduction to Compass Surveying, Bearings and Longitude & Latitude of a Line, Introduction to total station.
Levelling: Instrument used Object of levelling, Methods of levelling in brief, and Contour maps.
Chapter 4
Buildings: Selection of site for Buildings, Layout of Building Plan, Types of buildings, Plinth area, carpet area, floor space index, Introduction to building byelaws, concept of sun light & ventilation. Components of Buildings & their functions, Basic concept of R.C.C., Introduction to types of foundation
Chapter 5
Transportation: Introduction to Transportation Engineering; Traffic and Road Safety: Types and Characteristics of Various Modes of Transportation; Various Road Traffic Signs, Causes of Accidents and Road Safety Measures.
Chapter 6
Environmental Engineering: Environmental Pollution, Environmental Acts and Regulations, Functional Concepts of Ecology, Basics of Species, Biodiversity, Ecosystem, Hydrological Cycle; Chemical Cycles: Carbon, Nitrogen & Phosphorus; Energy Flow in Ecosystems.
Water Pollution: Water Quality standards, Introduction to Treatment & Disposal of Waste Water. Reuse and Saving of Water, Rain Water Harvesting. Solid Waste Management: Classification of Solid Waste, Collection, Transportation and Disposal of Solid. Recycling of Solid Waste: Energy Recovery, Sanitary Landfill, On-Site Sanitation. Air & Noise Pollution: Primary and Secondary air pollutants, Harmful effects of Air Pollution, Control of Air Pollution. . Noise Pollution Harmful Effects of noise pollution, control of noise pollution, Global warming & Climate Change, Ozone depletion, Greenhouse effect
Text Books:
1. Palancharmy, Basic Civil Engineering, McGraw Hill publishers.
2. Satheesh Gopi, Basic Civil Engineering, Pearson Publishers.
3. Ketki Rangwala Dalal, Essentials of Civil Engineering, Charotar Publishing House.
4. BCP, Surveying volume 1
LAND USE LAND COVER AND NDVI OF MIRZAPUR DISTRICT, UPRAHUL
This Dissertation explores the particular circumstances of Mirzapur, a region located in the
core of India. Mirzapur, with its varied terrains and abundant biodiversity, offers an optimal
environment for investigating the changes in vegetation cover dynamics. Our study utilizes
advanced technologies such as GIS (Geographic Information Systems) and Remote sensing to
analyze the transformations that have taken place over the course of a decade.
The complex relationship between human activities and the environment has been the focus
of extensive research and worry. As the global community grapples with swift urbanization,
population expansion, and economic progress, the effects on natural ecosystems are becoming
more evident. A crucial element of this impact is the alteration of vegetation cover, which plays a
significant role in maintaining the ecological equilibrium of our planet.Land serves as the foundation for all human activities and provides the necessary materials for
these activities. As the most crucial natural resource, its utilization by humans results in different
'Land uses,' which are determined by both human activities and the physical characteristics of the
land.
The utilization of land is impacted by human needs and environmental factors. In countries
like India, rapid population growth and the emphasis on extensive resource exploitation can lead
to significant land degradation, adversely affecting the region's land cover.
Therefore, human intervention has significantly influenced land use patterns over many
centuries, evolving its structure over time and space. In the present era, these changes have
accelerated due to factors such as agriculture and urbanization. Information regarding land use and
cover is essential for various planning and management tasks related to the Earth's surface,
providing crucial environmental data for scientific, resource management, policy purposes, and
diverse human activities.
Accurate understanding of land use and cover is imperative for the development planning
of any area. Consequently, a wide range of professionals, including earth system scientists, land
and water managers, and urban planners, are interested in obtaining data on land use and cover
changes, conversion trends, and other related patterns. The spatial dimensions of land use and
cover support policymakers and scientists in making well-informed decisions, as alterations in
these patterns indicate shifts in economic and social conditions. Monitoring such changes with the
help of Advanced technologies like Remote Sensing and Geographic Information Systems is
crucial for coordinated efforts across different administrative levels. Advanced technologies like
Remote Sensing and Geographic Information Systems
9
Changes in vegetation cover refer to variations in the distribution, composition, and overall
structure of plant communities across different temporal and spatial scales. These changes can
occur natural.
RHEOLOGY Physical pharmaceutics-II notes for B.pharm 4th sem students
Dissertation Defense Presentation
1. Measurement of Angular Correlation in b Quark Pair
Production at the LHC as a Test of Perturbative QCD
Dissertation Defense
Brian L. Dorney
Florida Institute of Technology
Dissertation Committee:
Marc Baarmand (advisor)
Ugur Abdulla (outside)
Daniel Batcheldor
Marcus Hohlmann
Ming Zhang
Brian L. Dorney 07/03/13
Dissertation Defense
1
2. The Standard Model...
...of Particle Physics
Describes interactions of
fermions and bosons
Image courtesy of MissMJ, “Standard Model of Elementary Particles,” Wikipedia, 2013.
Fermions: half-integer spin,
i.e. quarks and leptons
Bosons: integer spin, i.e. γ, g,
Z0, W±, and H
Incorporates “two” theories
Quantum Chromodynamics
Electroweak Theory
Quantum Electrodynamics
Quantum Flavordynamics
(i.e. weak interactions)
Brian L. Dorney 07/03/13
Dissertation Defense
2
3. Quantum Chromodynamics
Renormalizable nonabelian gauge
theory that describes interactions of
quarks and gluons
Anticharge screening
At high energies quarks and gluons
behave as free particles
Color confinement
As distance between quarks and gluons
increases their color charge increases
Asymptotic freedom
J. Beringer et al. (Particle Data Group), Phys. Rev. D86, 010001 (2012).
All searches for free quarks since 1977
have yielded negative results
Quarks form color singlet bound states
Perturbation Theory
Observables described by perturbative
series in terms of αS
Brian L. Dorney 07/03/13
Dissertation Defense
3
4. bb Production Mechanisms
Left image courtesy of D. Acosta et al., Phys. Rev. D71,092001 (2005).
Right image courtsey of M. Baarmand et al., CMS-AN-2010/022.
FCR gives rise to a back-to-back topology for the bb pair
In FEX a bb pair is created within the parent proton
Angle in transverse plane between the b and b is ~π radians
Only one member of the bb pair is involved in collision causing a wide range of
angular separations between the b and b
In GSP, a gluon splits into a bb pair
The b and b are roughly collinear w/small angular separation in the transverse plane
Brian L. Dorney 07/03/13
Dissertation Defense
4
5. Properties of B Hadrons
Daughters generally have
high impact parameters
Perpendicular distance
between particle trajectory
and primary vertex
Generally decay into
several charged
secondary particles
Makes it possible to find
the location of the B
hadron's decay
(i.e. secondary vertex)
Brian L. Dorney 07/03/13
Dissertation Defense
5
6. Properties of B Hadrons
Large semileptonic branching fraction
How often a B hadron decays to leptons+hadrons
B B l l X =
Bl l X
B Y
At LO, decay proceeds via emission of virtual W
boson and a charm quark
νμ
μ+
0.29
−0.25
B( B → μ νμ X) = 10.95
Brian L. Dorney 07/03/13
% as quoted by PDG
Dissertation Defense
6
7. Proton-Proton Collision
Underlying
Event
Spectator Partons
f k x1
h1 P 1
1
qk x1 P 1
1
1
k
k
q1 q 2 y
1
q
h2 P 2
k2
2
x2 P 2
2
FSR Included
Y
Jets
f k x2
2
Underlying
Event
ISR
Protons
Approach
Hard
Scattering
1
Parton
Shower
1
Decays
h1 h2 Y =∫0 dx 1∫0 dx2 ∑ ∑ f k x 1 f k x 2 q1 x1 P 1 q 2 x 2 P 2 y
Brian L. Dorney 07/03/13
7
k1
k2
1
2
Dissertation Defense
Hadronization
k1
k2
9. Large Hadron Collider
Image courtesy of LHC@home, http://lhcathome.web.cern.ch/LHCathome/LHC/lhc.shtml, 2013.
Brian L. Dorney 07/03/13
Dissertation Defense
9
10. Compact Muon Solenoid (CMS)
CMS Collaboration, Lucas Talyor, “CMS detector design,”
http://cms.web.cern/ch/news/cms-detector-design, 2013.
Brian L. Dorney 07/03/13
Dissertation Defense
10
11. CMS Coordinate System
+y
+y
+z
+x
x-axis points out of page
z-axis points into page
yz-plane
xy-plane
= −ln tan / 2
= 2 − 1
R =
p x p y
= 2 − 1
A = or R
pT =
2
2
2
CMS Collaboration, Detector Drawings, CMS-PHO-GEN-2012-002.
Brian L. Dorney 07/03/13
Dissertation Defense
11
2
13. Previous bb Angular Correlation
Measurements – LHC, ATLAS
Right: bb dijet production
cross section
ATLAS Collaboration. Eur. Phys. J. C, 71 (1846), 2011.
Disagreement at low Δφ
Full range of Δφ was not
studied
Cross section with
respect to ΔR has not
been presented
Brian L. Dorney 07/03/13
Dissertation Defense
13
14. Previous BB Angular Correlation
Measurements – LHC, CMS
CMS Collaboration, JHEP03(2011)136.
CMS Collaboration, JHEP03(2011)136.
BB production cross section
Overall uncertainty of 47% common to all data points
Brian L. Dorney 07/03/13
Dissertation Defense
14
15. Motivation
Why perform another bb angular correlation
measurement at LHC energy levels?
Large uncertainty on absolute cross section of previous
CMS results
Limited Δφ range covered in ATLAS study
Propose a new bb angular correlation measurement
to address these two concerns
Complimentary measurement using different
experimental technique and in differing phase-space
Angular correlations measured w.r.t. b-tagged jets
Brian L. Dorney 07/03/13
Dissertation Defense
15
16. Overview
b-jet
Two b-tagged jets
p
Experimental Signature
One of which has a muon
μ
Strategy
Select high purity sample of bb dijet events
X
Signal purity determined in data via System4
p
b-jet
Selection efficiency
Calculated from simulated PYTHIA events
Weighted by data trigger efficiency
Corrected by data-over-simulation scale factors (muon
reconstruction, jet energy resolution, b-tagging, etc...)
Data
SF =
Sim.
Measurement of differential cross section w.r.t. Δφ and ΔR
Brian L. Dorney 07/03/13
Dissertation Defense
16
17. Simulated Samples &
Monte-Carlo Event Generators
PYTHIA
Muon-enriched hard QCD process
Passed through Geant4 CMS detector simulation
MadGraph
CASCADE
Hard scattering: p p b b j for j = 0, 1, & 2 additional partons
Hard scattering: g g Q Q for Q = b
MadGraph and CASCADE passed to PYTHIA for parton
shower and hadronization
Not passed through Geant4 CMS detector simulation
Brian L. Dorney 07/03/13
Dissertation Defense
17
18. Data Samples
Proton-proton collision events collected in 2010 at
s=7 TeV with recorded integrated luminosity 3 pb-1
Two independent samples collected
Low-pT single-muon trigger, referred to as HLT_Mu7
Single-jet and multijet triggers
Use of muon triggers are a natural choice to select
bb data sample online
Jet triggers collect statistically independent sample
for measuring online selection efficiency Online
Brian L. Dorney 07/03/13
Dissertation Defense
18
19. Particle-Flow Event
Reconstruction in CMS
“Global event description”
Hits in CMS detector channels used to
form elements
Elements are linked together to form
blocks
Tracks, calorimeter clusters
Charged tracks linked to calorimeter clusters
Calorimeter clusters linked to calorimeter
clusters
Tracks linked to tracks
Blocks identified as particle-flow
candidates
Block formed from a charged track linked to a
HCAL cluster forms a particle-flow hadron
Brian L. Dorney 07/03/13
Dissertation Defense
CMS Collaboration, CMS PAS PFT-10-001, 2010.
19
20. Particle-Flow Jet
Reconstruction in CMS
Jets are clustered by the infrared and collinear safe
anti-kT particle-flow algorithm
Iterative clustering algorithm
Collection of particle-flow candidates used as input
Clusters particles into jets if the particles are within a
given distance parameter djet of the jet axis
Characterized by two resolution variables:
d kB = p
2a
Tk
d kl =min p , p
2a
Tk
Beam Resolution
2a
Tl
R
d
Cluster Resolution
2
kl
2
jet
For a = 1 (a = -1), kT (anti-kT) clustering algorithm
Brian L. Dorney 07/03/13
Dissertation Defense
20
21. Muon
Reconstruction in CMS
Global Muon reconstruction, i.e. “outside-in”
Standalone-muon track: reconstructed in muon detector
Standalone-muon track extrapolated to inner tracking
detector and required to match a tracker track
Global-muon track: track formed from combined fit of hits in
the standalone-muon and tracker track
Tracker Muon reconstruction, i.e. “inside-out”
Track reconstructed by inner tracking detector is extrapolated
to muon detector
Tracker-muon track: If this extrapolated track matches a
muon segment the tracker track is called a tracker-muon
Muon segment: track stub made of drift tube or cathode-strip
chamber hits
Brian L. Dorney 07/03/13
Dissertation Defense
21
22. Physics Object Matching
Objects are said to be matched if they are
within some parametric distance of each other
Example of matching
A generator-level jet and a reconstructed jet are
considered to be matched if the ΔR between them
is less than 0.25
Brian L. Dorney 07/03/13
Dissertation Defense
22
23. Physics Object Selection
Anti-kT particle-flow jets
Loose PF Jet ID
Distance parameter, djet = 0.5
pT > 30 GeV & |η| < 2.4
Muons
Tight Muon Selection
pT > 8 GeV & |η| < 2.1
This pT cut corresponds to plateau in online efficiency
Referred to as tight muons
Brian L. Dorney 07/03/13
Dissertation Defense
23
24. Muon Association
Tight muon found within a
jet referred to as the jet's
associated muon
Association uses a jet's
particle-flow constituents
If two or more tight muons
found the tight muon with
Rel
pT to jet axis
the highest
is taken
p jet p
∣ ×∣
p =
p
∣∣
Rel
T
Brian L. Dorney 07/03/13
Dissertation Defense
24
26. Online Selection
Data has at least one “offline” reconstructed tight muon
with HLT_Mu7 trigger object match
HLT_Mu7 trigger object is a muon (i.e. track) reconstructed by
the HLT_Mu7 trigger algorithm
ΔR matching, with ΔR < 0.5
The tight muon must be associated to a jet
Simulated PYTHIA events are weighted with Online
Simulated trigger information not used
Event weighting determined from η of highest pT tight muon
associated to a jet
Shown to be equivalent to a data-over-simulated efficiency
scale factor weighting
Brian L. Dorney 07/03/13
Dissertation Defense
26
28. Offline Preselection
At least one jet having an associated tight muon
with trigger-matched (ΔR < 0.5) object
No trigger-matched object criterion for simulation
At least one jet w/o an associated tight muon
The highest TCHE mu-jet and the highest TCHP
non-mu-jet must have ΔR > 0.6
Jets with (without) associated tight muons are
referred to as mu-jets (non-mu-jets)
Brian L. Dorney 07/03/13
Dissertation Defense
28
31. B-Tagging
Identification of jets arising from
the hadronization and decay of b
quarks
Signed impact parameter
significance (SIP)
Referred to as b jets
CMS Collaboration, CMS PAS BTV_07_002, 2008.
Impact parameter significance given by IP / IP
Impact parameter inherits the sign of the scalar product between the
IP and jet axis, tracks from B hadron decays favor positive SIP values
Track counting algo. orders a jet's tracks by decreasing SIP
Numeric discriminator formed by taking the SIP of the Nth track
Two versions, high eff. (TCHE, N = 2) and high purity (TCHP, N = 3)
Brian L. Dorney 07/03/13
Dissertation Defense
31
32. B-Tagging Selection
For TC discriminator values > X, the light (u, d, s, and g) jet
misidentification probability is Y
Form “operating points” which give specific values of Y
Loose (L), Y = 10%; Medium (M), Y = 1%; Tight (T), Y = 0.1%;
In each event highest TCHE mu-jet and highest TCHP non-mujet taken as a dijet pair
Event is finally selected if mu-jet (non-mu-jet) passes TCHEM
(TCHPT) operating point
TCHEM: TCHE > 3.30; TCHPT: TCHP > 3.41
Event is rejected if two or more mu-jets (non-mu-jets) pass TCHEM
(TCHPT), fraction of events rejected in data (sim.) is 0.7% (0.7%).
Brian L. Dorney 07/03/13
Dissertation Defense
32
34. Final Selection: Jet Kinematics
Brian L. Dorney 07/03/13
Dissertation Defense
34
35. Final Selection: Muon Kinematics
EWK contamination does not survive b-tagging selection
Brian L. Dorney 07/03/13
Dissertation Defense
35
36. Detector Response
ΔRReco
From true flavor bb dijets and their matched (ΔR < 0.25)
generator-level jets from final selected simulated events
ΔφReco
ΔφGen
ΔRGen
Off diagonal elements are an order of magnitude smaller
than their main diagonal counterparts
Bin-to-bin migration taken as negligible
Brian L. Dorney 07/03/13
Dissertation Defense
36
37. Purity Correction with System4
System of 4 equations in 4 unknowns, System4
Solves an “S x = b” system for each bin of ΔA
Designed to determine bin-by-bin bb signal purity in data
S = efficiency matrix; x = flavor vector; b = yields vector
Breaks analysis into four classes of cuts
TCHPT applied to non-mu-jet
TCHEM applied to mu-jet
Preselection
Both discriminators applied to both jets
Unknowns are the flavor content of preselected events
Transformed to purity of final selected events
Brian L. Dorney 07/03/13
Dissertation Defense
37
38. System4
Flavor
Vector
Efficiency Matrix
Unknowns
Description
Contents of preselected events by flavor.
First (second) letter is the flavor of the
mu-jet (non-mu-jet), X = non-b.
{ f BB , f BX , f XB , f XX }
Knowns
{f
TCHPT
{ B
TCHPT
,f
TCHPT
TCHEM
Description
,f
TCHEM
Both
Fraction of events passing cuts
}
TCHEM
, X
, B
, X
{ BB , BX , XB , XX }
{ BB , BX , XB , XX }
{ BB , BX , XB , XX }
Brian L. Dorney 07/03/13
Yields
Vector
}
B-tagging efficiencies
Ratios of dijet efficiency to single
jet efficiency
Dissertation Defense
38
39. System4 Toy MC
Use 100k pseudo-experiments for each bin of ΔA
Vary elements of yields vector & efficiency matrix by their
uncertainties
Solves “S x = b” via non-negative least squares algorithm
C. L. Lawson, R. H. Hanson, “Solving Least Squares Problems,”
Prentice-Hall, Inc., 1974.
Distributions of flavor vector elements and purity are
formed from all pseudo-experiments
Purity given as P IJ = IJ IJ f IJ / f Both
Fit with a Gaussian, mean (standard deviation) is set to the
central value (statistical uncertainty)
Brian L. Dorney 07/03/13
Dissertation Defense
39
40. bb Dijet Signal Purity in Data
Overall bb dijet signal purity in data: 93.3 ± 1.7 (stat.) %
Brian L. Dorney 07/03/13
Dissertation Defense
40
41. Online plus Offline Selection
Efficiency
H Sel
Sel =
H Gen
Taken from simulation as ratio of reconstructed bb
dijet to generated bb dijet ΔA distributions
Overall online plus offline efficiency Sel =17.1%
Brian L. Dorney 07/03/13
Dissertation Defense
41
42. Systematic Uncertainties
Calculated bin-by-bin in ΔA:
Signal purity
Muon reconstruction and identification efficiency scale factor
B-tagging efficiency scale factors
Jet energy correction (JEC)
Jet energy resolution (JER)
Fragmentation
Shape of online plus offline efficiency
Proton distributions functions
Taken as a flat value across all bins of ΔA:
Online efficiency
Recored integrated luminosity
Total syst. uncert. on absolute cross section +13.1/-9.8%
Brian L. Dorney 07/03/13
Dissertation Defense
42
43. Differential bb Dijet Production
Cross Section
Experimental cross section for ith bin of ΔA
N Data P bb
d
=
d A i
L A bin Sel
i
NData → raw number of final selected events
Pbb → bb dijet signal purity
L → recorded integrated luminosity
ΔAbin → bin width in ΔA
Sel → online plus offline selection efficiency
Brian L. Dorney 07/03/13
Dissertation Defense
43
44. Differential bb Dijet Production
Cross Section
Brian L. Dorney 07/03/13
Dissertation Defense
44
45. Comparison to Previous CMS
Results
Red: previous
CMS Results
Black: work
presented here
Brian L. Dorney 07/03/13
Dissertation Defense
45
46. Comparison with Theoretical
Preidctions of Perturbative QCD
All
Val
in n ues
b
e
lut ion
bso ect
A
S
ss
Cro
Brian L. Dorney 07/03/13
Dissertation Defense
46
47. Suggestions for Future Work
Extend study to full CMS pp collision dataset
Compare results with a complete NLO MC
event generator
Determine the fractions of bb pairs produced
by the FCR, FEX, and GSP mechanisms
Determine the double differential bb dijet
2
production cross section d / d A d E
Detemine the cross section as a function of ΔA
with n additional light jets in final state
Brian L. Dorney 07/03/13
Dissertation Defense
47
51. Previous BB Angular Correlation
Measurements – LHC, CMS
CMS Collaboration, JHEP03(2011)136.
CMS Collaboration, JHEP03(2011)136.
BB production cross section
Overall uncertainty of 47% common to all data points
Brian L. Dorney 07/03/13
Dissertation Defense
51
52. Corrections Made to Simulated
PYTHIA Sample
The analysis takes the online plus offline efficiency with
respect to ΔA from the simulated PYTHIA sample
Simulation has been weighted/corrected by:
Data-driven jet energy resolution scale factors jet-by-jet (CMS
PAS JME-10-011)
Semileptonic branching fraction scale factors for direct B
hadron to muon decays jet-by-jet (presented herein)
Data trigger efficiency event-by-event (presented herein)
Data-driven muon reco. and ID efficiency scale factor, muonby-muon and mu-jet-by-mu-jet (CMS PAS MUO-10-004)
Beauty, charm, and light b-tagging efficiency scale factors for
TCHEM and TCHPT jet-by-jet (Official CMS SFs)
Brian L. Dorney 07/03/13
Dissertation Defense
52
53. Jet Energy Resolution Scale
Factor
Corrects the JER in simulated samples to what is
observed in data
p
prime
T
=p
Gen
T
SF JER⋅ p
Reco
T
−p
Gen
T
SFJER reported in CMS PAS JME-10-011
JM
E10
-
01
1
SFJER =
Brian L. Dorney 07/03/13
Dissertation Defense
53
54. Branching Fraction Scale Factor
PDG branching fraction:
0.0029
B B X PDG = 0.10956−0.0025
PYTHIA branching fraction:
−3
B B X PYTHIA = 0.1048±1.663⋅10
Measurements made from B+, B0, B0s, b-baryons, Bc,
and charge conjugates
For both PDG and PYTHIA numbers given above
Cascade b → c → μX decays are not considered in
above PDG or PYTHIA numbers
They are not direct decays
Brian L. Dorney 07/03/13
Dissertation Defense
54
55. Branching Fraction Scale Factor
For true flavor b jets w/direct b to mu decays
SF BF =
B
PDG
B
PYTHIA
0.027
= 1.044− 0.024
For true flavor b jets w/o direct b to mu decays
non−
SF BF
=
1 − B PDG
1 − B PYTHIA
0.0032
= 0.9948−0.0028
Use the hadron ancestry chain method to identify which
case generator-level true flavor b jets belong to
Reconstructed true flavor b jets use their matched generator-level
jets to determine which case they belong to
Brian L. Dorney 07/03/13
Dissertation Defense
55
56. Muon Reconstruction and
Identification Efficiency Scale Factor
Efficiency to reconstruct and identify muons in CMS
detector presented in CMS PAS MUO-10-004
For both data and simulated samples
M
U
O
-1
000
4
Observables obtained from tight muons (or the jets they
are found w/in) are weighted by muon-by-muon (jet-by-jet)
with the muon reconstruction and identification efficiency
scale factor
Brian L. Dorney 07/03/13
Dissertation Defense
56
57. B-Tagging Efficiency Scale
Factors
Two sets of functions, { SF b , SF c , SF l }
Note SFc = SFb with double the quoted uncertainty
Separate functions for light, charm, and beauty jets
One set for each TCHEM and TCHPT
Parameterized in terms of jet pT
Scale factor functions are used jet-by-jet in simulated events
Randomly upgrades (degrades) tagged (untagged) jets in
simulation
Ensures b-tagging efficiencies in simulated events agree with
what is observed in data
Brian L. Dorney 07/03/13
Dissertation Defense
57
58. B-Tagging Efficiency Scale
Factors
Jet with transverse momentum pT and flavor i will
SF i = SF i pT and Sim. = Sim. pT
have
i
i
Obtain a uniformly distributed random number R such
that R ∈ [ 0, 1 ]
For SF i 1 & jet is untagged, calculate
1− SF i
f=
SF i
1− Sim.
i
If R < f, tag the jet (i.e. upgrade)
This is the fraction of jets we need to tag in simulation
For SF i 1 & jet is tagged
If R > SF i untag the jet (i.e. downgrade)
This is the fraction of jets we fail to tag in data
Brian L. Dorney 07/03/13
Dissertation Defense
58
59. TCHEM B-Tagging Efficiency
Scale Factor
Brian L. Dorney 07/03/13
Dissertation Defense
Note SFb = SFc with
twice the uncertainty
59
60. TCHPT B-Tagging Efficiency
Scale Factor
Brian L. Dorney 07/03/13
Dissertation Defense
Note SFb = SFc with
twice the uncertainty
60
61. B-Tagging Efficiency Scale
Factors, Factorizable at Low ΔR?
Study conducted by D. Bloch
at my request
Looked at b-tagging efficiency
scale factors in dijet events
D. Bloch, b tag meeting, 12th Dec. 2012
Mu-jet tagged by TCHEM
Non-mu-jet (“away- jet”) tagged
by TCHPT
Conclude scale factors are
factorizable at low ΔR
D. Bloch, b tag meeting, 12th Dec. 2012
Brian L. Dorney 07/03/13
Dissertation Defense
61
62. PYTHIA Hard QCD Process
All hard scattering processes of the form:
qi qi q j q j
qi qi g g
qi g qi g
g g qi qi
q i q j qi q j
gg gg
Where q is any flavor quark (top excluded) and
g is a gluon
Brian L. Dorney 07/03/13
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62
63.
p T in PYTHIA
Mandelstam Variables
Where pi are 4-vectors
s = p A p B
t = p A − pC
2
u = p A− p D
2
2
pC
pD
time
pA
pB
Form pT
1
pT =
t u − m3 m4
s
Brian L. Dorney 07/03/13
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63
64. Infrared & Collinear Safe Jet
Algorithms
Jet definition is insensitive to “infrared and
collinear divergences”
What does this Mean?
Theoretical predictions of the inclusive jet cross
section must be finite at all orders
Experimentally the jet definition does not
drastically change in the presence of additionally
emitted collinear or soft particles
i.e. Event topology/jet multiplicity is relatively constant
Brian L. Dorney 07/03/13
Dissertation Defense
64
65. Jet Matching
Before the Selection record the ΔR
of all possible reconstructed and
generator-level jet pairings
For conservative measure apply ΔR
matching criterion of 0.25
For reco jets with pT > 10 GeV
First inflection point at ΔR ≈ 0.3
1.19% remain unmatched
0.01% have two possible matches, no
jet with three possible matches
Fraction of unmatched reco jets
with pT > 30 GeV is ≈0.1%
Brian L. Dorney 07/03/13
Dissertation Defense
65
66. Assignment of True Flavor to
Jets in Simulated Samples
True flavor of a generator-level jet is determined from the jet's
three highest generator-level constituents
Heaviest-flavor hadron ancestor in the decay chain of these
three particles is assigned as the generator-level jet's flavor
Occurrence of a generator-level particle having more than one
mother in a decay chain was found to be negligible (≈0.03%)
True flavor of a reconstructed jet is taken from its matched
generator-level jet
True flavor of unmatched reconstructed jets assigned as light
Brian L. Dorney 07/03/13
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66
67. Tight Muon Selection
Muon is both a global muon and a tracker muon.
Global track
Global track has at least one muon chamber hit.
2
Tracker track required to be matched to muon
segments in at least two muon stations.
Tracker track has nhits ≥ 10.
fit's / n.D.o.F. 10.
At least one of these hits is in the pixel detector
Transverse impact parameter w.r.t. PV
∣d xy∣ 2 mm.
Brian L. Dorney 07/03/13
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67
68. Loose PFJetID
Neutral hadron energy fraction < 0.99
Neutral EM energy fraction < 0.99
Number of pfConstituents > 1
Charged hadron energy fraction > 0
Charged EM energy fraction < 0.99
Charged multiplicity > 0
Brian L. Dorney 07/03/13
Dissertation Defense
68
69. Trigger Muon Object Matching
Offline tight muons are matched to HLT_Mu7 trigger
objects
Matching Criteria
Only HLT_Mu7 trigger objects
ΔR between the tight muon and trigger object is less than 0.5
Matching is one-to-one
i.e. trigger objects matched to one tight muon are not considered for
other matches, and vice versa
Trigger object match candidates ordered by increasing ΔR
Tight muon-trigger object match with lowest ΔR is taken as the
matched pair
Brian L. Dorney 07/03/13
Dissertation Defense
69
70. Online Efficiency
SFOnline
SFOnline
Online Efficiency
Trigger Efficiency Weighting
Comparison
Online efficiency scale factor SFOnline flat for muon pT > 8 GeV
Noticeable variation w.r.t. muon η
Brian L. Dorney 07/03/13
Dissertation Defense
70
71. Trigger Efficiency Weighting
Comparison
Performed analysis using simulated trigger information
Event-by-event weighting: SF Online high
high is from the highest p muon, having a HLT_Mu7 trigger matched object,
associated to a jet
T
Observe that data trigger efficiency weighting is equivalent to online
efficiency scale factor weighting
Brian L. Dorney 07/03/13
Dissertation Defense
71
72. Determination of Online
Efficiency
Data collected by single-jet and mutlijet triggers provides
statistically independent sample for online efficiency
measurement
Event Selection
Only one offline reconstructed muon present
Muon is associated to a jet
Association uses the jet's particle-flow constituents
Jet passes TCHEM operating point (i.e. TCHE > 3.3)
Object Selection
Jet with muon must have pT > 30 GeV
Muon must pass the Tight Muon Selection with |η| < 2.1
Brian L. Dorney 07/03/13
Dissertation Defense
72
73. Determination of Online
Efficiency – Results
Efficiency defined as Online = N matched / N all
Nmatched → # of tight muons in a given p or bin, associated to a b-tagged jet,
T
matched with an HLT_Mu7 trigger object
Nall → # of tight muons in a given pT or bin that are associated to a b-tagged jet
Online efficiency Online = 85.5±1.1 stat.−1.5 syst. %
3.9
Brian L. Dorney 07/03/13
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73
74. Determination of Online
Efficiency – Systematic Uncertainties
Methodology taken from CMS PAS-MUO-10-004
Independently varied the following
Increased selection beyond Tight Muon Selection
Jet b-tagging operating point changed to TCHPT
Muon's track was required to be the track that
determined the jet's TCHE value
With and w/o the b-tagging requirement under both
the Tight Muon Selection and the more stringent
muon selection
Brian L. Dorney 07/03/13
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74
75. Online Efficiency
Online Efficiency
Determination of Online
Efficiency – Systematic Uncertainties
Black: nominal distribution
Red: increased selection beyond Tight Muon Selection
Brian L. Dorney 07/03/13
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75
76. Online Efficiency
Online Efficiency
Determination of Online
Efficiency – Systematic Uncertainties
Black: nominal distribution
Blue: jet passes TCHPT operating point
Brian L. Dorney 07/03/13
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76
77. Online Efficiency
Online Efficiency
Determination of Online
Efficiency – Systematic Uncertainties
Black: nominal distribution
Green: muon's track determines jet's TCHE value
Brian L. Dorney 07/03/13
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77
79. Determination of Online
Efficiency – Systematic Uncertainties
Effect on online efficiency
With & w/o B-tagging
under Normal &
Increased Selection
0.00%
Increase B-Tagging
-0.1%
0.00%
Increased Muon Sel
0.0%
+3.9%
Muon's track
determines TCHE
0.0%
+0.6%
Total
-1.5%
-1.5%
+3.9%
3.9
−1.5
Online efficiency Online = 85.5±1.1 stat.
Brian L. Dorney 07/03/13
Dissertation Defense
syst.%
79
80. Online Efficiency Cross Check
Efficiency of a different
low-pT single-muon
trigger published in
CMS PAS MUO-10-004
Referred to as HLT_Mu9
Measured efficiency of
HLT_Mu9 using my
technique
Find agreement with
published values
Brian L. Dorney 07/03/13
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80
84. Summary of Event Selection
Number of events passing each stage of the
event selection
Fraction of events remaining after each stage
of event selection w.r.t. previous stage allows
for direct comparison of data and simulation
Brian L. Dorney 07/03/13
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84
85. Δφ & ΔR Resolution
For all true flavor bb dijet pairs record A Reco− AGen
ΔA represents Δφ or ΔR
RMS of this distribution taken as resolution on ΔA
Brian L. Dorney 07/03/13
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85
86. Detector Response – Revisited
Decrease Δφ detector response matrix bin size by 2
Bin size now approximately five times Δφ resolution
Observe off diagonal elements in “larger” bin size are actually
part of main diagonal
Conclusion: bin-to-bin migration is negligible
Brian L. Dorney 07/03/13
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86
87. System4
Flavor
Vector
Efficiency Matrix
Dijet Tagging Efficiencies
TCHEM
ij = i
Description
First (second) letter is the flavor of the
mu-jet (non-mu-jet), i, j = B or X.
TCHPT
j
Non-b Tagging Efficiencies
all
X=
nc
all
Description
all
Sim.
all c
nc n l
Brian L. Dorney 07/03/13
nl
all
Yields
Vector
Sim.
all l
Efficiency to tag a non-b jet
nc n l
Dissertation Defense
87
88. System4
Flavor
Vector
Efficiency Matrix
Beta Factors
Both Tag
IJ =
IJ
TCHEM
I
TCHPT
J
Alpha & Gamma Factors
IJ =
IJ =
Mu Tag
IJ
TCHEM
I
Non Mu Tag
IJ
TCHPT
J
Brian L. Dorney 07/03/13
Yields
Vector
Description
Ratio of dijet efficiency to single jet
efficiency
Description
As above
Define κIJ = {αIJ, βIJ, γIJ}
As above
Dissertation Defense
88
89. System4
Flavor
Vector
Efficiency Matrix
Beta Factors
Description
Both Tag
IJ =
IJ
TCHEM
I
TCHPT
J
Dijet Efficiency Example
Tag
Both Tag
IJ
=
N IJ
Tag
Tag
N IJ N IJ
Brian L. Dorney 07/03/13
Yields
Vector
Ratio of dijet efficiency to single jet
efficiency
Description
Example dijet efficiency, similarly
for other two cases
Dissertation Defense
89
90. System4
Flavor
Vector
Efficiency Matrix
Purity Definition
P BB = BB BB f BB / f
Brian L. Dorney 07/03/13
Yields
Vector
Description
Both
First (second) letter is the flavor of the
mu-jet (non-mu-jet), i, j = B or X.
Dissertation Defense
90
91. System4 – IJ Factors, Δφ
Brian L. Dorney 07/03/13
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91
92. System4 – IJ Factors, ΔR
Brian L. Dorney 07/03/13
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92
93. System4 – IJ Factors,
Shape Investigation
Factors generally increase with decreasing
angular separation between two jets
Investigated whether factor behavior is due to
differing kinematic behavior
Investigated shape of factors in bins of jet
transverse momentum and absolute
pseudorapidity
Brian L. Dorney 07/03/13
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93
94. System4 – IJ Factors,
Binned by Mu-Jet pT
Approximately
uniform shape
over all pT bins
Brian L. Dorney 07/03/13
Dissertation Defense
94
95. System4 – IJ Factors,
Binned by Jet pT
Approximately
uniform shape
over all pT bins
Brian L. Dorney 07/03/13
Dissertation Defense
95
96. System4 – IJ Factors,
Binned by Non-Mu-Jet pT
Approximately
uniform shape
over all pT bins
Brian L. Dorney 07/03/13
Dissertation Defense
96
97. System4 – IJ Factors,
Binned by Jet |η|
Uniform shape
over all |η| bins
Brian L. Dorney 07/03/13
Dissertation Defense
97
98. System4 – IJ Factors,
Binned by Jet |η|
Uniform shape
over all |η| bins
Brian L. Dorney 07/03/13
Dissertation Defense
98
99. System4 – IJ Factors,
Binned by Jet |η|
Uniform shape
over all |η| bins
Brian L. Dorney 07/03/13
Dissertation Defense
99
100. System4 – IJ Factors,
Track Mismatching
Investigated possibility of track mismatching as a contributor to
shapes of κIJ factors
For each mu-jet (non-mu-jet) track that determines jet's TCHE
(TCHP) referred to as the b-tagging track
ΔR between parent mu-jet (non-mu-jet) and b-tagging track plotted
against the ΔR between the adjacent non-mu-jet (mu-jet) and the
b-tagging track
Symbolically referred to as trackTCHE (trackTCHP) for the mu-jet (non-mu-jet)
Here “adjacent” refers to the other member of the dijet object
In O(107) events, O(10) events have instances of track mismatching
i.e. Negligible, too rare to describe shapes of κIJ factors
Brian L. Dorney 07/03/13
Dissertation Defense
100
101. System4 – Track Mismatching
Mu-Jet Passes TCHEM, b-tagging = trackTCHE
Imagine y=x line
Entries falling
below line
indicate track
mismatching
i.e. mu-jet's
b-tagging track
is closer in
ηφ-plane to the
non-mu-jet
Brian L. Dorney 07/03/13
Dissertation Defense
101
102. System4 – Track Mismatching
Non-Mu-Jet Passes TCHPT, b-tagging = trackTCHP
Imagine y=x line
Entries falling
above line
indicate track
mismatching
i.e. non-mu-jet's
b-tagging track
is closer in
ηφ-plane to the
mu-jet
Brian L. Dorney 07/03/13
Dissertation Defense
102
103. System4 – Track Mismatching
Both Jets Pass Operating Pts, b-tagging = trackTCHE
Imagine y=x line
Entries falling
below line
indicate track
mismatching
i.e. mu-jet's
b-tagging track
is closer in
ηφ-plane to the
non-mu-jet
Brian L. Dorney 07/03/13
Dissertation Defense
103
104. System4 – Track Mismatching
Both Jets Pass Operating Pts, b-tagging = trackTCHP
Imagine y=x line
Entries falling
above line
indicate track
mismatching
i.e. non-mu-jet's
b-tagging track
is closer in
ηφ-plane to the
mu-jet
Brian L. Dorney 07/03/13
Dissertation Defense
104
105. System4 – Minimum ΔR
Separation
Spike in first bin of ΔR of κIJ factors
Could be caused by poorly reconstructed and/or
fake jets being used in System4 dijet pair
Investigated requiring minimum ΔR separation
between jets used in dijet pair
Brian L. Dorney 07/03/13
Dissertation Defense
105
106. System4 – Minimum ΔR
Separation
Reduction in spiking κIJ behavior when going from
ΔR > 0.5 to ΔR > 0.6
Values of κIJ don't vary substantially when moving
from ΔR > 0.6 to ΔR > 0.7
Brian L. Dorney 07/03/13
Dissertation Defense
106
107. System4 – Correlation of IJ Factors
Order pairs of κIJ's made from all bin of ΔA
i.e. { { (αIJ, βIJ) }, { (αIJ, γIJ) }, { (γIJ, βIJ) } }
Correlation coefficients ρ determined from
each set of ordered pairs
αIJ weakly correlated with βIJ and γIJ
βIJ and γIJ strongly correlated
Brian L. Dorney 07/03/13
Dissertation Defense
107
108. System4 – Event Rejection
Concerns
mu-jet multi.
Fraction of events that would be rejected for System4 is negligible
non-mu-jet multi.
In data (sim.) for cut stage 2, TCHPT applied to non-mu-jet, have 0.8% (0.7%) events with
two or more non-mu-jets passing TCHPT
In data (sim.) for cut stage 3, TCHEM applied to mu-jet, have 0.14% (0.15%) events with
two or more mu-jets passing TCHEM
Note: the event rejection is not used for cut cases of System4
Brian L. Dorney 07/03/13
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108
109. System4 – Closure Test
Split Simulated PYTHIA sample into two statistically
independent datasets
Efficiency matrix taken from even events
Yields vector taken from odd events
System4 solution obtained from toy MC method in odd
events compared to the true solution in odd events
Four closure tests performed
Nominal
Using κIJ = 1
Reweighting gluon splitting events by factor of ½
Reweighting gluon splitting events by factor of 2
Brian L. Dorney 07/03/13
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109
110. System4 – Closure Test, ΔR
Better
agreement
using κIJ
Behavior of
attributed to
small statistics
of XB dijet case
Brian L. Dorney 07/03/13
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110
111. System4 – Closure Test, ΔR
With GSP
events
reweighted by
factor of ½
Behavior of
attributed to
small statistics
of XB dijet case
Brian L. Dorney 07/03/13
Dissertation Defense
111
112. System4 – Closure Test, ΔR
With GSP
events
reweighted by
factor of 2
Behavior of
attributed to
small statistics
of XB dijet case
Brian L. Dorney 07/03/13
Dissertation Defense
112
113. System4 – Closure Test, Δφ
Better
agreement
using κIJ
Behavior of
attributed to
small statistics
of XB dijet case
Brian L. Dorney 07/03/13
Dissertation Defense
113
114. System4 – Closure Test, Δφ
With GSP
events
reweighted by
factor of ½
Behavior of
attributed to
small statistics
of XB dijet case
Brian L. Dorney 07/03/13
Dissertation Defense
114
115. System4 – Closure Test, Δφ
With GSP
events
reweighted by
factor of 2
Behavior of
attributed to
small statistics
of XB dijet case
Brian L. Dorney 07/03/13
Dissertation Defense
115
116. System4 – Results From Data, ΔR
Behavior of fXB
attributed to
small statistics
of XB dijet case
Brian L. Dorney 07/03/13
Dissertation Defense
116
117. System4 – Results From Data, Δφ
Behavior of fXB
attributed to
small statistics
of XB dijet case
Dissertation Defense
Δφ
Δφ
Brian L. Dorney 07/03/13
Δφ
Δφ
117
118. B Jet Transverse Momentum
Residuals
Post Preselection
Post Final Selection
Post Final Selection
Reco
Gen
For true flavor b jets and their matched generator-level jets, studied: p T − pT
Means of distributions slightly positive with large RMS
Conclude that the residuals are consistent with zero within their statistical uncertainties
A small fraction of final selected true flavor b jets with pT > 30 GeV are matched
with generator-level jets with pT < 30 GeV
Vast majority of these cases are within one standard deviation of 30 GeV
Brian L. Dorney 07/03/13
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118
119. Shape of Jet pT in Final Event Sample,
Binned by Δφ
Highest pT jet in bb
dijet candidate
0
4
Highest pT Jet
4
2
Highest pT Jet
3
2
4
Highest pT Jet
Brian L. Dorney 07/03/13
Dissertation Defense
3
4
Highest pT Jet
119
120. Shape of Jet pT in Final Event Sample,
Binned by Δφ
Lowest pT jet in bb
dijet candidate
0
4
Lowest pT Jet
4
2
Lowest pT Jet
3
2
4
Lowest pT Jet
Brian L. Dorney 07/03/13
Dissertation Defense
3
4
Lowest pT Jet
120
121. Shape of Jet pT in Final Event Sample,
Binned by ΔR
0.6 R1.4
1.4 R2.3
2.3 R3.2
Leading Jet pT
Leading Jet pT
Leading Jet pT
3.2 R4.1
Highest pT
jet in bb dijet
candidate
Brian L. Dorney 07/03/13
Leading Jet pT
Dissertation Defense
4.1 R5.0
Leading Jet pT
121
122. Shape of Jet pT in Final Event Sample,
Binned by ΔR
0.6 R1.4
1.4 R2.3
2.3 R3.2
Leading Jet pT
Leading Jet pT
Leading Jet pT
3.2 R4.1
Lowest pT jet
in bb dijet
candidate
Brian L. Dorney 07/03/13
Leading Jet pT
Dissertation Defense
4.1 R5.0
Leading Jet pT
122
123. Systematic Uncertainty,
Shape of Online Plus Offline Eff.
Differing kinematic behavior between data and
simulation could adversely affect cross section
Affect would be most pronounced in
uncertainties in the shape of the online plus
offline selection efficiency
Investigated in similar manner to what was
presented in JHEP03(2011)136.
However analysis performed in three jet |η| bins
Brian L. Dorney 07/03/13
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123
124. Systematic Uncertainty,
Shape of Online Plus Offline Eff.
Top: difference between data
and simulation in the average
pT of the highest pT jet in the
bb dijet candidate
Bottom: online plus offline
selection efficiency w.r.t. pT of
highest jet in bb dijet
candidate
All plots from final selected
events
Brian L. Dorney 07/03/13
Dissertation Defense
124
125. Systematic Uncertainty,
Shape of Online Plus Offline Eff.
Differences btw data and
sim. used to modify Sel via:
Prime
Sel
〈 pT 〉 Sim.
Performed in three |ηjet| bins
= Sel⋅ 1
〈 pT 〉 Data − 〈 pT 〉 Sim.
{ [0,2.4),[0.0.9),[0.9,2.4)}
Performed using highest
and lowest pT jet in the bb
dijet candidate
Six variations in total
Brian L. Dorney 07/03/13
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125
126. Systematic Uncertainty,
Shape of Online Plus Offline Eff.
Differences btw data and
sim. used to modify Sel via:
Prime
Sel
〈 pT 〉 Sim.
Performed in three |ηjet| bins
= Sel⋅ 1
〈 pT 〉 Data − 〈 pT 〉 Sim.
{ [0,2.4),[0.0.9),[0.9,2.4)}
Performed using highest
and lowest pT jet in the bb
dijet candidate
Six variations in total
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127. Systematic Uncertainty,
Shape of Online Plus Offline Eff.
Differences btw data and
sim. used to modify Sel via:
Prime
Sel
〈 pT 〉 Sim.
Performed in three |ηjet| bins
= Sel⋅ 1
〈 pT 〉 Data − 〈 pT 〉 Sim.
{ [0,2.4),[0.0.9),[0.9,2.4)}
Performed using highest
and lowest pT jet in the bb
dijet candidate
Six variations in total
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128. Systematic Uncertainty,
Shape of Online Plus Offline Eff.
Brian L. Dorney 07/03/13
Modified online plus offline
selection efficiencies used to
recompute the cross section
Maximum difference, for each
bin of ΔA, between nominal
cross section and the six new
cross sections taken as
systematic uncertainty
Dissertation Defense
128
129. Systematic Uncertainty,
Shape of Online Plus Offline Eff.
Brian L. Dorney 07/03/13
Modified online plus offline
selection efficiencies used to
recompute the cross section
Maximum difference, for each
bin of ΔA, between nominal
cross section and the six new
cross sections taken as
systematic uncertainty
Dissertation Defense
129
130. Systematic Uncertainty,
Signal Purity
Mismodeling of the shapes of kIJ factors
System4 was solved using varied αIJ and using simultaneously varied βIJ and γIJ
true
Closure
Difference f BB − f BB between System4 solution and the true solution
obtained in the nominal closure test
Varied shapes of efficiencies in the numerators of the kIJ equations in identical
fashion to what was done for the shape of the online plus offline selection
efficiency
prime
true
Closure
Solution in data modified by f BB = f BB f BB − f BB
prime
Purity in data recalculated using f BB
Possible differences in relative fraction of charm and light jets between
data and simulation
The value of n c n l is varied up and down by a factor of two while holding the
value n all n all of fixed.
l
c
all
all
Cross section recalculated for each of the above variations
Differences between nominal and varied cases are added in quadrature and
assigned as the systematic uncertainty for signal purity
Brian L. Dorney 07/03/13
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130
131. Systematic Uncertainty,
Muon Reco & ID Eff. Scale Factor
Muon reconstruction and identification scale factor
taken from CMS PAS MUO-10-004
Observables obtained from tight muons (or the jets
they are found w/in) are weighted muon-by-muon (jetby-jet) with the scale factor
For systematic uncertainty
Scale factor is varied up (down) by its total uncertainty
resulting in a -1.2% (+1.2%) change in the total cross section
Brian L. Dorney 07/03/13
Dissertation Defense
131
132. Systematic Uncertainty,
B-Tagging Eff. Scale Factors
B-tagging scale factors {SF b , SF c , SF l } for TCHEM
and TCHPT are varied up and down by their
uncertainties
Both scale factors changed at the same time in the
same direction
Beauty and charm scale factors are correlated,
varied simultaneously
Light scale factor uncorrelated, varied independently
Results of variations added in quadrature
Scale factor variations up (down) resulted in a
-3.2% (+6.7%) change in total cross section
Brian L. Dorney 07/03/13
Dissertation Defense
132
133. Systematic Uncertainty,
JEC and JER
The jet energy correction is varied up and down by its
uncertainty
The up (down) variations of the JEC resulted in a -5.6% (+9.1%)
change in the total cross section
The JER in the simulation is smeared jet-by-jet via
prime
Reco
p T = p Gen SF JER⋅ p T − p Gen
T
T
SFJER =
JM
E10
-0
11
SFJER variations resulted in a +1.7% change in the total cross
section
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133
134. Systematic Uncertainty,
Fragmentation
An additional PYTHIA sample was generated
using Peterson/SLAC fragmentation function
Generator-level jet pT distributions between
two PYTHIA samples are compared
Differences are used to modify the reco and
generator-level jet pT in the nominal case
Same is done for muons
Brian L. Dorney 07/03/13
Dissertation Defense
134
135. Systematic Uncertainty,
Fragmentation
The transverse momentum of reconstructed and
generator-level jets and muons modified via
p
prime
T
f Lund pT − f Peterson pT
= pT
m
Modifications are performed before the
selection is applied
Effect on total cross section found to be +0.4%
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135
136. Systematic Uncertainty,
Proton PDFs
Uncertainty due to proton PDFs assessed by
reweighting technique
Contribution of PDF to cross section can be
assigned a weight wi
1
1
k1
k2
h1 h2 Y =∫0 dx 1∫0 dx2 ∑ ∑ f k x 1 f k x 2 q1 x1 P 1 q 2 x 2 P 2 y
k1
1
1
k2
2
1
k
k
h1 h2 Y =∫0 dx 1∫0 dx2 ∑ ∑ f k x 1 f k x 2 w i q1 x1 P 1 q2 x 2 P 2 y
k1
k2
1
2
1
2
f k x1 ; Si f k x2 ; S i
Where wi given by: w i = f x ; S f x ; S
k
1
0
k
2
0
1
1
Brian L. Dorney 07/03/13
2
2
Dissertation Defense
136
137. Systematic Uncertainty,
Proton PDFs
In practice this means simulated events are
reweighted by wi
Three PDF sets were used in reweighting
Maximum deviation per bin of ΔA between the
nominal cross section and the reweighted cross
sections is taken as the systematic uncertainty
CTEQ66m, MSTW2008-nlo, NNPDF2.0
Effect on total cross section found to be -1.0%
wi=
f k x1 ; Si f k x2 ; S i
1
f k x1 ; S0 f k x2 ; S0
1
Brian L. Dorney 07/03/13
2
Dissertation Defense
2
137
138. Systematic Uncertainty,
Summary
Right: systematic uncertainties
on total cross section
Uncertainty sources listed
under the shape variations and
theory headings do not follow
standard “down/up” description
Down/upwards headings give
direction of parameter variation
while the sign of the value gives
effect on total cross section
Sign of the value again gives
effect on total cross section
Total systematic uncertainty on
total cross section +13.1/-9.8%
Dominat systematics are the JEC
and b-tagging scale factors
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