Doppler broadening
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This document discusses Doppler broadening, which is the broadening of spectral lines caused by the Doppler effect of random thermal motion of molecules. Doppler broadening results in a lack of sharpness in spectral lines and a distribution of redshifted and blueshifted wavelengths due to a range of atomic speeds along the line of sight. The broadening depends on factors like the frequency, mass of emitting particles, and temperature, with higher temperatures resulting in greater broadening due to increased particle velocities. Doppler broadening also occurs in nuclear reactors as fuel temperature rises and uranium nuclei move more rapidly.
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This document discusses spectroscopy techniques, specifically atomic absorption spectroscopy (AAS). It begins by explaining the electromagnetic spectrum and photon interactions with matter. It then describes different types of spectroscopy including absorption, fluorescence, and phosphorescence. Beer-Lambert law is introduced which states that absorbance is directly proportional to concentration. Instrumental components of a spectrophotometer such as light sources, monochromators, sample holders, and detectors are outlined. The principles of atomic absorption spectroscopy are explained including hollow cathode lamps and atomic excitation. Advantages of AAS compared to atomic emission spectroscopy are provided.
HMT-Conduction1.pptx
The document provides an overview of key concepts in heat transfer including conduction, convection, and radiation. It defines heat transfer as the transfer of energy from one system to another due to a temperature difference. The three modes of heat transfer - conduction, convection, and radiation - are described. Conduction occurs via molecular interactions within a material. Convection involves the transfer of energy between a surface and adjacent moving fluid. Radiation transfers energy electromagnetically without a medium. Key equations for each mode are also presented, such as Fourier's law of conduction and Newton's law of cooling for convection.
Breakdowngass
The document discusses electrical breakdown in gases. It explains that gases are commonly used as dielectric mediums in electrical apparatus due to their insulating properties. However, when high voltages are applied, electrical breakdown can occur through ionization. The Townsend theory and streamer theory are presented as explanations for the breakdown mechanism under different conditions. Collision processes, mobility of ions and electrons, diffusion, and mean free path are also discussed. The document further explains the ionization process and Townsend's criteria for electrical breakdown in gases.
NMR SPECTROSCOPY
NMR SPECTROSCOPY ,Relaxation,longitudinal / spin- spin relaxation,transverse / spin- spin relaxation,Shielding of proton ,Deshielding of proton,CHEMICAL SHIFT,Factors Influencing Chemical Shift,Inductive effect, Vander Waal’s deshielding,Anisotropic effect (space effect),Hydrogen bonding
,SPLITTING OF THE SIGNALS,COUPLING CONSTANT,NMR SIGNAL IN VARIOUS COMPOUND
Radiation
This document discusses concepts related to radiation heat transfer. It covers the following key points:
1) Electromagnetic radiation is emitted by all objects with a temperature above absolute zero and travels at the speed of light. The amount of radiation emitted increases rapidly with temperature.
2) Radiation can be characterized by its wavelength and frequency. Shorter wavelengths correspond to more energetic radiation.
3) Blackbody radiation obeys Planck's law, which describes the spectrum of electromagnetic radiation emitted by a black body in thermal equilibrium based on its temperature.
Nmr
The document provides an overview of Nuclear Magnetic Resonance Spectroscopy (NMR). It explains that NMR is used to study nuclei such as 1H, 13C, 15N, 19F, and 31P. When placed in an external magnetic field, these nuclei with spin align with or against the field, absorbing photons and flipping between energy states. The energy required depends on field strength and the nucleus. NMR signals provide information on the number, type, and connectivity of nuclei in a molecule.
Nuclear magnetic resonance spectroscopy
This document provides an overview of Nuclear Magnetic Resonance Spectroscopy (NMR). NMR is a powerful tool for determining organic structures. It measures the absorption of radiofrequency photons by atomic nuclei with spin in an applied magnetic field. The frequency of absorption depends on the magnetic field strength and chemical environment of the nucleus. Analysis of NMR spectra provides information on a molecule's structure, including the number and type of protons and their connectivity.
NMR.pptx
NMR-DEFINITION -EXPLANATION-RELAXATION PROCESS-SIGNIFICANCE OF NMR-CHEMICAL SHIFT- DOUBLE RESONANCE TECHNIQUE-ENDOR-NOE-FT NMR-NMR IMAGING
Electronic.ppt
This document discusses electronic spectroscopy techniques such as ultraviolet-visible (UV-vis) spectroscopy and chiroptical spectroscopy. It describes how UV-vis spectroscopy can be used to study electronic transitions in molecules, detect functional groups, and perform quantitative analysis. Chiroptical spectroscopy techniques like circular dichroism and optical rotary dispersion are used to determine stereochemistry by measuring differences in absorption of left and right circularly polarized light. Selection rules and origins of electronic transitions are also summarized.
Electronic Spectroscopy.ppt
This document discusses electronic spectroscopy techniques such as ultraviolet-visible (UV-vis) spectroscopy and chiroptical spectroscopy. It describes how UV-vis spectroscopy can be used to study electronic transitions in molecules, detect functional groups, and perform quantitative analysis. The fundamentals of UV-vis spectroscopy, including electronic transitions, selection rules, solvent effects, and absorption intensity are summarized. Chiroptical spectroscopy techniques like circular dichroism and optical rotary dispersion are also introduced.
Mechanisms of heat transfer
This document summarizes the three main mechanisms of heat transfer: conduction, convection, and radiation. It explains key concepts for each type of transfer. Conduction involves the transfer of kinetic energy between molecules in direct contact. Convection involves the transfer of heat by the circulation of fluids (gases or liquids). Radiation involves the emission and absorption of electromagnetic waves. The document provides detailed explanations of these processes, factors that influence each type of transfer, and examples like the greenhouse effect and vacuum flasks.
INTERACTION OF IONIZING RADIATION WITH MATTER
The document discusses the interaction of ionizing radiation with matter. It describes the main interaction processes including photoelectric effect, Compton scattering, and pair production. For radiation therapy, Compton scattering is the most important interaction as it allows high energy beams to penetrate tissue more uniformly depositing dose. The photoelectric effect is more significant for diagnostic radiology due to its dependence on atomic number.
Radiation_1.ppt
1) The document discusses basic principles of thermal radiation, including that it is emitted by matter due to oscillations of electrons sustained by thermal energy. Radiation can be emitted or absorbed by matter, resulting in heat transfer.
2) Radiation behaves both as particles (photons) and waves, and is characterized by wavelength and frequency. Thermal radiation is confined to the infrared, visible, and ultraviolet regions of the electromagnetic spectrum.
3) A blackbody is an idealized perfect emitter and absorber of radiation. It has a characteristic spectral distribution of radiation that depends only on its temperature, as described by Planck's law and the Stefan-Boltzmann law.
NEPHAR 407 NMR_19.pdf
1. NMR spectroscopy involves subjecting atomic nuclei to radiofrequency pulses within a strong magnetic field, causing them to absorb and emit electromagnetic radiation. The frequency absorbed depends on the magnetic field strength and properties of the nuclear isotope.
2. 1H and 13C NMR spectra provide information about the number and connectivity of protons and carbons in an organic molecule. Chemical shifts indicate the nuclear environment, while spin-spin splitting patterns reveal neighboring nuclei.
3. Analysis of NMR spectra involves determining the number of signal types, their integration intensities, chemical shifts, and splitting patterns to elucidate the compound's structure.
Similar to Doppler broadening (20)
More from Zeeshan Khalid
Conference poster final
This document presents a mathematical model for analyzing heat transfer during phase change processes in a latent heat thermal energy storage (LHTES) unit. The model considers heat transfer between a heat transfer fluid flowing through a circular tube and phase change material (PCM) contained in the cylindrical shell. Dimensionless governing equations are derived to model forced convection in the fluid and natural convection during PCM melting. An analytical solution is obtained for temperature distribution using exponential integral functions. Results show interface position varies with dimensionless time and is affected by parameters like Stefan number, Biot number, and Rayleigh number. Graphs illustrate increased melting rate with natural convection and effect of varying Stefan number and Biot number on interface position.
Conference ppt
This document presents a novel method called the Eigenfunction Expansion Method (EFEM) for analytically solving transient heat conduction problems with phase change in cylindrical coordinates. The method involves formulating the governing equations and associated boundary conditions, introducing coefficients, solving the eigenvalue problems, and representing the solution as a series expansion of the eigenfunctions. Dimensionless parameters are introduced to simplify the problem. The EFEM is then applied to solve a one-dimensional phase change problem. Results show that increasing the number of terms in the series expansion decreases the truncation error and that the Stefan number affects the melting fraction evolution over time.
Two lense system
- When using a two lens optical system, the magnification of the final image is calculated by multiplying the magnifications of each individual lens.
- To calculate the image from the first lens, treat it as the object for the second lens. The object distance for the second lens is the distance from the first lens' image to the second lens.
- A two converging lens system will produce a real, upright final image, while a converging-diverging system will produce a virtual, inverted final image.
Elementary particles and their properties
The document discusses the elementary particles that make up the universe. It explains that all matter is composed of atoms, which themselves are made of electrons, protons, and neutrons. Protons and neutrons are composed of quarks. The elementary particles are divided into three families with similar properties. Tables are provided that summarize the key properties of each particle such as mass, electric charge, strong charge, and weak charge. There are four fundamental forces that act on these particles: gravitation, electromagnetism, strong nuclear force, and weak nuclear force.
Moleculer physics lect 1
This document discusses molecules and the different types of bonds that hold atoms together to form compounds. It describes ionic bonds, which form when one atom transfers electrons to another, and covalent bonds, which form when atoms share electrons. The document also discusses molecular spectra arising from rotational and vibrational energy levels of molecules, and how infrared spectroscopy can analyze molecular vibrations. Potential energy graphs illustrate the attractive and repulsive forces between atoms at different distances that determine molecular structure.
Laser produced plasmas ppt
This document discusses laser produced plasmas. It defines plasma as a quasi-neutral gas that exhibits collective behavior and comprises most of the visible universe. Plasma can be formed by applying enough energy, such as from electromagnetic fields, to tear electrons from neutral atoms. Laser produced plasmas are generated by focusing high intensity laser pulses on solid targets. Typical laser produced plasmas have temperature, density, and expansion velocity profiles that depend on the laser parameters. Applications of laser produced plasmas include use in medicine, as x-ray sources, and probing radiation biology with characteristic x-rays.
Zeeman Effect
The Zeeman effect is the splitting of a spectral line into multiple spectral lines when in the presence of a magnetic field. It was first observed in 1896 by Dutch physicist Pieter Zeeman when he placed a sodium flame between magnetic poles and observed the broadening of spectral lines. Zeeman's discovery earned him the 1902 Nobel Prize in Physics. The pattern and amount of splitting provides information about the strength and presence of the magnetic field.
Physics of atom
This document discusses the physics of atoms and their subatomic particles. It describes the Bohr model of the atom, which depicts electrons orbiting the nucleus in fixed orbits or shells. When electrons move between these shells, energy is absorbed or emitted in the form of radiation. The document also outlines the discoveries of subatomic particles like electrons, protons, and neutrons through experiments such as Rutherford's gold foil experiment and Chadwick's work. Finally, it provides the names, symbols, masses, and charges of the basic particles that make up an atom: protons, neutrons, and electrons.
Parallel universes
The document discusses four levels of possible parallel universes. Level I proposes that other universes may exist beyond the observable bounds of our own, as space is believed to be infinite. Level II suggests that other universes could have formed from bubbles in the early inflation of the universe. Level III describes the multiverse theory arising from the quantum mechanical many worlds interpretation. Level IV encompasses other mathematical structures that may constitute universes under different physical laws.
CT scan
CT scans use X-rays and computers to create detailed images of the inside of the body. CT scanning was independently developed in the 1970s by Godfrey Hounsfield and Allan Cormack. A CT scan works by using an X-ray device and detector that rotate around the body, detecting differences in radiation absorption as they pass through tissues. The data is then used to construct a series of cross-sectional images of the bones, muscles, fat, and organs inside the body. CT scans allow doctors to see internal structures in great detail and find diseases that may not be visible on regular X-rays.
Nuclear physics 3 lectures
Radioactive decay occurs when an unstable atom emits particles or radiation to become more stable. There are three types of radioactive decay: alpha particle emission, beta particle emission, and gamma ray emission. Nuclear physics lectures covered radioactive decay and neutron interactions with nuclei. Neutrons can elastically scatter off nuclei through potential scattering. Neutrons can also be absorbed by nuclei to form an excited compound nucleus that then decays, emitting an energetic particle. The concept of neutron cross section is used to quantify the likelihood of interaction between an incident neutron and a target nucleus.
nuclear binding energy
This document provides an overview of basic nuclear physics concepts. It discusses the structure of atoms including protons, neutrons, and electrons. It defines terms like atomic number, mass number, and isotopes. It explains concepts such as binding energy, radioactive decay modes (alpha, beta, gamma), activity, and half-life. Radioactive decay is described as the process by which unstable atoms emit particles or radiation to become more stable. Common decay types and their products are outlined.
Quantum mechanics of black holes
This document discusses the quantum mechanics of black holes. It notes that quantum mechanics allows for time-reversed transitions between states, which contradicts classical general relativity descriptions of black holes. Specifically, general relativity says that a black hole absorbing another object can occur, but the reverse process of emission cannot. However, quantum mechanics predicts both absorption and emission are possible. Hawking resolved this contradiction by showing that black holes can spontaneously emit elementary particles via a quantum process, allowing the time-reversed transition and upholding the second law of thermodynamics at the quantum scale.
Liquification of gases
There are three main methods for liquefying gases:
1. Applying sufficient pressure to gases below their critical temperature to cause liquefaction. For example, liquefying carbon dioxide which has a critical temperature of 304K.
2. Making gases do work against an external force, such as in a steam engine, causing them to lose energy and lower in temperature.
3. Forcing gases through a nozzle or porous plug, making them do work against their own internal forces and lose energy, potentially reaching liquefaction after multiple repetitions of expanding through restrictions.
Ampere’s law
Ampere's law relates the magnetic field around a closed loop to the electric current passing through the loop. It states that the line integral of the magnetic field around the loop equals the net current passing through the loop times the permeability of free space. The document provides examples of using Ampere's law to calculate magnetic fields for various current carrying wire configurations, including inside and outside a long straight wire, inside a solenoid, and inside and outside a toroidal coil.
Diffraction
When waves encounter obstacles like slits, they diffract or bend around the edges. Diffraction can be explained by Huygens' principle, which says each point on a wavefront acts as a new source. For a single slit, the new wavefront shape is determined by combining spherical wavelets from points across the slit. There are two types of diffraction: Fresnel, where distances are finite, and Fraunhofer, where incident waves are plane waves. X-ray diffraction uses wavelengths comparable to atomic sizes to determine crystal and molecular structures.
More from Zeeshan Khalid (17)
Recently uploaded
_Extraction of Ethylene oxide and 2-Chloroethanol from alternate matrices Li...
How do you know your food is safe?
Last Friday was world World Food Safety Day, facilitated by the Food and Agriculture Organization of the United Nations (FAO) and the World Health Organization (WHO) in which the slogan rightly says, 'food safety is everyone's business'. Due to this, I thought it would be worth sharing some data that I have worked on in this field!
Working at Markes International has really opened my eyes (and unfortunately my friends and family 🤣) to food safety and quality, especially with my recent application work on ethylene oxide and 2-chloroethanol residues in foodstuffs, as of the biggest global food recalls in history was and is still being implemented by the Rapid alert system for food and feed (RASFF) in 2021, for high levels of these carcinogenic compounds.
8.Isolation of pure cultures and preservation of cultures.pdf
Isolation of pure culture, its various method.
fermented food science of sauerkraut.pptx
This ppt contains the production of a fermented food name - sauerkraut
JAMES WEBB STUDY THE MASSIVE BLACK HOLE SEEDS
The pathway(s) to seeding the massive black holes (MBHs) that exist at the heart of galaxies in the present and distant Universe remains an unsolved problem. Here we categorise, describe and quantitatively discuss the formation pathways of both light and heavy seeds. We emphasise that the most recent computational models suggest that rather than a bimodal-like mass spectrum between light and heavy seeds with light at one end and heavy at the other that instead a continuum exists. Light seeds being more ubiquitous and the heavier seeds becoming less and less abundant due the rarer environmental conditions required for their formation. We therefore examine the different mechanisms that give rise to different seed mass spectrums. We show how and why the mechanisms that produce the heaviest seeds are also among the rarest events in the Universe and are hence extremely unlikely to be the seeds for the vast majority of the MBH population. We quantify, within the limits of the current large uncertainties in the seeding processes, the expected number densities of the seed mass spectrum. We argue that light seeds must be at least 103 to 105 times more numerous than heavy seeds to explain the MBH population as a whole. Based on our current understanding of the seed population this makes heavy seeds (Mseed > 103 M⊙) a significantly more likely pathway given that heavy seeds have an abundance pattern than is close to and likely in excess of 10−4 compared to light seeds. Finally, we examine the current state-of-the-art in numerical calculations and recent observations and plot a path forward for near-future advances in both domains.
Compexometric titration/Chelatorphy titration/chelating titration
Classification
Metal ion ion indicators
Masking and demasking reagents
Estimation of Magnisium sulphate
Calcium gluconate
Complexometric Titration/ chelatometry titration/chelating titration, introduction, Types-
1.Direct Titration
2.Back Titration
3.Replacement Titration
4.Indirect Titration
Masking agent, Demasking agents
formation of complex
comparition between masking and demasking agents,
Indicators/Metal ion indicators/ Metallochromic indicators/pM indicators,
Visual Technique,PM indicators (metallochromic), Indicators of pH, Redox Indicators
Instrumental Techniques-Photometry
Potentiometry
Miscellaneous methods.
Complex titration with EDTA.
(June 12, 2024) Webinar: Development of PET theranostics targeting the molecu...
(June 12, 2024) Webinar: Development of PET theranostics targeting the molecu...Scintica Instrumentation
Targeting Hsp90 and its pathogen Orthologs with Tethered Inhibitors as a Diagnostic and Therapeutic Strategy for cancer and infectious diseases with Dr. Timothy Haystead.ESA/ACT Science Coffee: Diego Blas - Gravitational wave detection with orbita...
ESA/ACT Science Coffee: Diego Blas - Gravitational wave detection with orbita...Advanced-Concepts-Team
Presentation in the Science Coffee of the Advanced Concepts Team of the European Space Agency on the 07.06.2024.
Speaker: Diego Blas (IFAE/ICREA)
Title: Gravitational wave detection with orbital motion of Moon and artificial
Abstract:
In this talk I will describe some recent ideas to find gravitational waves from supermassive black holes or of primordial origin by studying their secular effect on the orbital motion of the Moon or satellites that are laser ranged.Evidence of Jet Activity from the Secondary Black Hole in the OJ 287 Binary S...
Wereport the study of a huge optical intraday flare on 2021 November 12 at 2 a.m. UT in the blazar OJ287. In the binary black hole model, it is associated with an impact of the secondary black hole on the accretion disk of the primary. Our multifrequency observing campaign was set up to search for such a signature of the impact based on a prediction made 8 yr earlier. The first I-band results of the flare have already been reported by Kishore et al. (2024). Here we combine these data with our monitoring in the R-band. There is a big change in the R–I spectral index by 1.0 ±0.1 between the normal background and the flare, suggesting a new component of radiation. The polarization variation during the rise of the flare suggests the same. The limits on the source size place it most reasonably in the jet of the secondary BH. We then ask why we have not seen this phenomenon before. We show that OJ287 was never before observed with sufficient sensitivity on the night when the flare should have happened according to the binary model. We also study the probability that this flare is just an oversized example of intraday variability using the Krakow data set of intense monitoring between 2015 and 2023. We find that the occurrence of a flare of this size and rapidity is unlikely. In machine-readable Tables 1 and 2, we give the full orbit-linked historical light curve of OJ287 as well as the dense monitoring sample of Krakow.
Anti-Universe And Emergent Gravity and the Dark Universe
Recent theoretical progress indicates that spacetime and gravity emerge together from the entanglement structure of an underlying microscopic theory. These ideas are best understood in Anti-de Sitter space, where they rely on the area law for entanglement entropy. The extension to de Sitter space requires taking into account the entropy and temperature associated with the cosmological horizon. Using insights from string theory, black hole physics and quantum information theory we argue that the positive dark energy leads to a thermal volume law contribution to the entropy that overtakes the area law precisely at the cosmological horizon. Due to the competition between area and volume law entanglement the microscopic de Sitter states do not thermalise at sub-Hubble scales: they exhibit memory effects in the form of an entropy displacement caused by matter. The emergent laws of gravity contain an additional ‘dark’ gravitational force describing the ‘elastic’ response due to the entropy displacement. We derive an estimate of the strength of this extra force in terms of the baryonic mass, Newton’s constant and the Hubble acceleration scale a0 = cH0, and provide evidence for the fact that this additional ‘dark gravity force’ explains the observed phenomena in galaxies and clusters currently attributed to dark matter.
Describing and Interpreting an Immersive Learning Case with the Immersion Cub...
Current descriptions of immersive learning cases are often difficult or impossible to compare. This is due to a myriad of different options on what details to include, which aspects are relevant, and on the descriptive approaches employed. Also, these aspects often combine very specific details with more general guidelines or indicate intents and rationales without clarifying their implementation. In this paper we provide a method to describe immersive learning cases that is structured to enable comparisons, yet flexible enough to allow researchers and practitioners to decide which aspects to include. This method leverages a taxonomy that classifies educational aspects at three levels (uses, practices, and strategies) and then utilizes two frameworks, the Immersive Learning Brain and the Immersion Cube, to enable a structured description and interpretation of immersive learning cases. The method is then demonstrated on a published immersive learning case on training for wind turbine maintenance using virtual reality. Applying the method results in a structured artifact, the Immersive Learning Case Sheet, that tags the case with its proximal uses, practices, and strategies, and refines the free text case description to ensure that matching details are included. This contribution is thus a case description method in support of future comparative research of immersive learning cases. We then discuss how the resulting description and interpretation can be leveraged to change immersion learning cases, by enriching them (considering low-effort changes or additions) or innovating (exploring more challenging avenues of transformation). The method holds significant promise to support better-grounded research in immersive learning.
Summary Of transcription and Translation.pdf
Hello Everyone Here We are Sharing You with The process of protien Synthesis in very short points you will be Able to understand It Very well
Sexuality - Issues, Attitude and Behaviour - Applied Social Psychology - Psyc...
A proprietary approach developed by bringing together the best of learning theories from Psychology, design principles from the world of visualization, and pedagogical methods from over a decade of training experience, that enables you to: Learn better, faster!
Direct Seeded Rice - Climate Smart Agriculture
Direct Seeded Rice - Climate Smart AgricultureInternational Food Policy Research Institute- South Asia Office
PPT on Direct Seeded Rice presented at the three-day 'Training and Validation Workshop on Modules of Climate Smart Agriculture (CSA) Technologies in South Asia' workshop on April 22, 2024.
Randomised Optimisation Algorithms in DAPHNE
Slides from talk:
Aleš Zamuda: Randomised Optimisation Algorithms in DAPHNE .
Austrian-Slovenian HPC Meeting 2024 – ASHPC24, Seeblickhotel Grundlsee in Austria, 10–13 June 2024
https://ashpc.eu/
Methods of grain storage Structures in India.pdf
•Post-harvestlossesaccountforabout10%oftotalfoodgrainsduetounscientificstorage,insects,rodents,micro-organismsetc.,
•Totalfoodgrainproductioninindiais311milliontonnesandstorageis145mt.InIndia,annualstoragelosseshavebeenestimated14mtworthofRs.7,000croreinwhichinsectsaloneaccountfornearlyRs.1,300crores.
•InIndiaoutofthetotalproduction,about30%ismarketablesurplus
•Remaining70%isretainedandstoredbyfarmersforconsumption,seed,feed.Hence,growerneedstoragefacilitytoholdaportionofproducetosellwhenthemarketingpriceisfavourable
•TradersandCo-operativesatmarketcentresneedstoragestructurestoholdgrainswhenthetransportfacilityisinadequate
Immersive Learning That Works: Research Grounding and Paths Forward
We will metaverse into the essence of immersive learning, into its three dimensions and conceptual models. This approach encompasses elements from teaching methodologies to social involvement, through organizational concerns and technologies. Challenging the perception of learning as knowledge transfer, we introduce a 'Uses, Practices & Strategies' model operationalized by the 'Immersive Learning Brain' and ‘Immersion Cube’ frameworks. This approach offers a comprehensive guide through the intricacies of immersive educational experiences and spotlighting research frontiers, along the immersion dimensions of system, narrative, and agency. Our discourse extends to stakeholders beyond the academic sphere, addressing the interests of technologists, instructional designers, and policymakers. We span various contexts, from formal education to organizational transformation to the new horizon of an AI-pervasive society. This keynote aims to unite the iLRN community in a collaborative journey towards a future where immersive learning research and practice coalesce, paving the way for innovative educational research and practice landscapes.
SDSS1335+0728: The awakening of a ∼ 106M⊙ black hole⋆
Context. The early-type galaxy SDSS J133519.91+072807.4 (hereafter SDSS1335+0728), which had exhibited no prior optical variations during the preceding two decades, began showing significant nuclear variability in the Zwicky Transient Facility (ZTF) alert stream from December 2019 (as ZTF19acnskyy). This variability behaviour, coupled with the host-galaxy properties, suggests that SDSS1335+0728 hosts a ∼ 106M⊙ black hole (BH) that is currently in the process of ‘turning on’. Aims. We present a multi-wavelength photometric analysis and spectroscopic follow-up performed with the aim of better understanding the origin of the nuclear variations detected in SDSS1335+0728. Methods. We used archival photometry (from WISE, 2MASS, SDSS, GALEX, eROSITA) and spectroscopic data (from SDSS and LAMOST) to study the state of SDSS1335+0728 prior to December 2019, and new observations from Swift, SOAR/Goodman, VLT/X-shooter, and Keck/LRIS taken after its turn-on to characterise its current state. We analysed the variability of SDSS1335+0728 in the X-ray/UV/optical/mid-infrared range, modelled its spectral energy distribution prior to and after December 2019, and studied the evolution of its UV/optical spectra. Results. From our multi-wavelength photometric analysis, we find that: (a) since 2021, the UV flux (from Swift/UVOT observations) is four times brighter than the flux reported by GALEX in 2004; (b) since June 2022, the mid-infrared flux has risen more than two times, and the W1−W2 WISE colour has become redder; and (c) since February 2024, the source has begun showing X-ray emission. From our spectroscopic follow-up, we see that (i) the narrow emission line ratios are now consistent with a more energetic ionising continuum; (ii) broad emission lines are not detected; and (iii) the [OIII] line increased its flux ∼ 3.6 years after the first ZTF alert, which implies a relatively compact narrow-line-emitting region. Conclusions. We conclude that the variations observed in SDSS1335+0728 could be either explained by a ∼ 106M⊙ AGN that is just turning on or by an exotic tidal disruption event (TDE). If the former is true, SDSS1335+0728 is one of the strongest cases of an AGNobserved in the process of activating. If the latter were found to be the case, it would correspond to the longest and faintest TDE ever observed (or another class of still unknown nuclear transient). Future observations of SDSS1335+0728 are crucial to further understand its behaviour. Key words. galaxies: active– accretion, accretion discs– galaxies: individual: SDSS J133519.91+072807.4
Recently uploaded (20)
_Extraction of Ethylene oxide and 2-Chloroethanol from alternate matrices Li...
_Extraction of Ethylene oxide and 2-Chloroethanol from alternate matrices Li...
8.Isolation of pure cultures and preservation of cultures.pdf
8.Isolation of pure cultures and preservation of cultures.pdf
Compexometric titration/Chelatorphy titration/chelating titration
Compexometric titration/Chelatorphy titration/chelating titration
(June 12, 2024) Webinar: Development of PET theranostics targeting the molecu...
(June 12, 2024) Webinar: Development of PET theranostics targeting the molecu...
ESA/ACT Science Coffee: Diego Blas - Gravitational wave detection with orbita...
ESA/ACT Science Coffee: Diego Blas - Gravitational wave detection with orbita...
Evidence of Jet Activity from the Secondary Black Hole in the OJ 287 Binary S...
Evidence of Jet Activity from the Secondary Black Hole in the OJ 287 Binary S...
Anti-Universe And Emergent Gravity and the Dark Universe
Anti-Universe And Emergent Gravity and the Dark Universe
Describing and Interpreting an Immersive Learning Case with the Immersion Cub...
Describing and Interpreting an Immersive Learning Case with the Immersion Cub...
Juaristi, Jon. - El canon espanol. El legado de la cultura española a la civi...
Juaristi, Jon. - El canon espanol. El legado de la cultura española a la civi...
Sexuality - Issues, Attitude and Behaviour - Applied Social Psychology - Psyc...
Sexuality - Issues, Attitude and Behaviour - Applied Social Psychology - Psyc...
Immersive Learning That Works: Research Grounding and Paths Forward
Immersive Learning That Works: Research Grounding and Paths Forward
SDSS1335+0728: The awakening of a ∼ 106M⊙ black hole⋆
SDSS1335+0728: The awakening of a ∼ 106M⊙ black hole⋆
Doppler broadening
- 1. Doppler Broadening M.Zeeshan Khalid 09050610-039
- 2. Introduction • It is the broadening of the spectral line due to Doppler Effect of the random thermal motion of the molecules. • Lack of sharpness in the spectrum line causes the broadening and is related to the distribution of velocities of the atoms or molecules. • Causes red shifted and blue shifted wavelengths
- 3. • Emitting atoms are in motion with a range of speeds Δν along the line of sight to the observer then Doppler Broadening is given as • For a gas of atoms of mass m at a temperature T, the velocity dispersion is given by where k is the Boltzmann constant (1.38 × 10−23 J K−1)
- 4. Thermal Doppler broadening • Atoms and molecules move in a haphazard direction with average velocity is given as (1/2mv2 )= 3/2kT • The spreading of the spectral line due to the temperature of the emitting medium is called as thermal Doppler broadening. • Spreading of the spectral line depends on the frequency, mass of the emitting particles and the temperature.
- 6. Doppler broadening on nuclear reactors • The Doppler effect arises when the temperature of the fuel changes. • When the uranium is heated, its nuclei move more rapidly in random directions, and therefore generate a wider range of relative neutron speeds. • Pebble bed nuclear reactors
- 7. Doppler Broadening Applications and other causes • Thermal Doppler broadening • Causes of velocity distribution Turbulent motion Accretion disc • Stark broadening