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This document discusses the luminosity function (LF) of galaxies, which measures the number of galaxies per magnitude interval. It defines mean and specific LFs and explains why LFs are important for understanding galaxy spatial distribution, geometry of the universe, and testing formation scenarios. The LF can also be used to test the Tully-Fisher relation for disk galaxies. Dynamical friction causes galaxy evolution over time, leading to variation in LFs between clusters and within individual clusters. Early type galaxies have higher LFs in clusters, while spirals have similar LFs in fields and clusters.
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- Specifically, it states that if the farther satellite had the same mass but was twice the distance, it would feel only one quarter the force, so its mass would need to be four times greater to feel the same force.
Are Young Galaxies Visible? - Partridge & Peebles 1967, ApJ 147, 686
This document summarizes a 1967 paper by Partridge and Peebles that modeled the formation and early evolution of galaxies to assess the possibility of detecting young galaxies. The model predicted that galaxies would go through a brief but very luminous phase after about 100 million years, with luminosities over 100 times their current brightness. However, searches failed to find these predicted bright young galaxies. Later models incorporating dark matter found that galaxies would assemble more gradually, be less massive, and have lower and more complex luminosities than the original model predicted.
Evidence ofr mature_bulges_and_an_inside_out_quenching_phase_3_billion_years_...
This document presents evidence that massive galaxies at redshift 2.2 (~3 billion years after the Big Bang) undergo an "inside-out quenching" process, where star formation is quenched first in the inner regions and later in the outer disks. High-resolution observations of 22 star-forming galaxies show that the most massive galaxies already have dense bulges similar to local spheroids, while still actively forming stars in their outer disks. The data suggests star formation is suppressed from the inside out on timescales of less than 1 Gyr in the centers and up to a few Gyr in the outer disks, as an "inside-out quenching wave" propagates through the galaxies. This provides insights into how
Comets: Delving into the Heart of the Matter
Ryan Laird presented on the Survey of Ensemble Physical Properties of Cometary Nuclei (SEPPCoN) project. The presentation aimed to investigate the physical properties of Jupiter-family comet nuclei, including size distribution, albedo, color, rotation, and bulk density. SEPPCoN analyzed over 100 Jupiter-family comet targets using ground-based visible and infrared observations to determine geometric albedos, sizes, and other properties to better understand the origins and evolution of comet nuclei and their connection to Kuiper belt objects. Preliminary findings from SEPPCoN showed successful detection of 64 of 91% of the targeted comet sample, with only 16 showing signs of outgassing.
Soosalu crustal structure_beneath_the_faroe_islands_from_teleseismic_receiver...
Using receiver function analysis of seismic data recorded by 45 broadband seismometers on Streymoy Island, Faroe Islands, we estimate:
1) The depth of the converting boundary beneath the Faroe Islands is between 29-32 km, which represents conversion from a region of high-velocity lower crust rather than the crust-mantle boundary.
2) Forward modeling suggests this high-velocity lower crust is at least 6 km thick.
3) The thick high-velocity lower crust is interpreted to result from intrusion of magma into the pre-existing continental crust during continental breakup, rather than underplating of igneous material at the base of the crust.
GWs.ppt
1) Gravitational waves are ripples in spacetime produced by accelerated masses like binary star systems.
2) They propagate at the speed of light and stretch and compress spacetime in two polarizations.
3) Ground-based detectors like LIGO and VIRGO have detected gravitational waves, indirectly confirming their existence. Space-based detectors like LISA are proposed to detect different sources like supermassive black holes.
The celestial clouds- GALAXY
Galaxies come in different shapes and classifications. Elliptical galaxies are round or elliptical shapes and contain older stars with little gas or new star formation. Spiral galaxies have a disk and spiral arms, with younger stars in the arms and older stars in the center. Irregular galaxies have a chaotic mix of stars, gas and dust without a clear shape. The document discusses the formation and properties of these different galaxy types. It also describes how galaxies are grouped into clusters and superclusters within the larger universe.
Stellar tidal streams_in_spiral_galaxies_of_the_local_volume
This pilot survey used modest aperture telescopes to image 8 nearby spiral galaxies in order to search for stellar tidal streams. Ultra-deep imaging revealed 6 previously undetected extensive (up to 30 kpc) stellar structures likely from tidally disrupted satellites. A diversity of tidal feature morphologies was found, including great circle-like streams, remote shells, and jets emerging from disks. Simulations predict tidal debris should be common and match the observed variety, providing evidence minor mergers have shaped disk galaxies since z=1.
HL Galaxy Metabolism
Contributed talk at "Galaxy Metabolism" meeting in Sydney, Australia (2009). I'm disappointed there is no "science" category on Slideshare.
Similar to Galaxy (14)
Multi wavelenth Observations and Surveys of Galaxy Clusters
Multi wavelenth Observations and Surveys of Galaxy Clusters
EMU M.Sc. Thesis Presentation "Dark Matter; Modification of f(R) or WIMPS M...
EMU M.Sc. Thesis Presentation "Dark Matter; Modification of f(R) or WIMPS M...
ILOA Galaxy Forum Europe 2013 - dark matter in galaxies - dr benoit famaey
ILOA Galaxy Forum Europe 2013 - dark matter in galaxies - dr benoit famaey
Are Young Galaxies Visible? - Partridge & Peebles 1967, ApJ 147, 686
Are Young Galaxies Visible? - Partridge & Peebles 1967, ApJ 147, 686
Evidence ofr mature_bulges_and_an_inside_out_quenching_phase_3_billion_years_...
Evidence ofr mature_bulges_and_an_inside_out_quenching_phase_3_billion_years_...
Soosalu crustal structure_beneath_the_faroe_islands_from_teleseismic_receiver...
Soosalu crustal structure_beneath_the_faroe_islands_from_teleseismic_receiver...
Stellar tidal streams_in_spiral_galaxies_of_the_local_volume
Stellar tidal streams_in_spiral_galaxies_of_the_local_volume
Recently uploaded
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.
Mending Clothing to Support Sustainable Fashion_CIMaR 2024.pdf
Ozturkcan, S., Berndt, A., & Angelakis, A. (2024). Mending clothing to support sustainable fashion. Presented at the 31st Annual Conference by the Consortium for International Marketing Research (CIMaR), 10-13 Jun 2024, University of Gävle, Sweden.
20240520 Planning a Circuit Simulator in JavaScript.pptx
Evaporation step counter work. I have done a physical experiment.
(Work in progress.)
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.
EWOCS-I: The catalog of X-ray sources in Westerlund 1 from the Extended Weste...
Context. With a mass exceeding several 104 M⊙ and a rich and dense population of massive stars, supermassive young star clusters
represent the most massive star-forming environment that is dominated by the feedback from massive stars and gravitational interactions
among stars.
Aims. In this paper we present the Extended Westerlund 1 and 2 Open Clusters Survey (EWOCS) project, which aims to investigate
the influence of the starburst environment on the formation of stars and planets, and on the evolution of both low and high mass stars.
The primary targets of this project are Westerlund 1 and 2, the closest supermassive star clusters to the Sun.
Methods. The project is based primarily on recent observations conducted with the Chandra and JWST observatories. Specifically,
the Chandra survey of Westerlund 1 consists of 36 new ACIS-I observations, nearly co-pointed, for a total exposure time of 1 Msec.
Additionally, we included 8 archival Chandra/ACIS-S observations. This paper presents the resulting catalog of X-ray sources within
and around Westerlund 1. Sources were detected by combining various existing methods, and photon extraction and source validation
were carried out using the ACIS-Extract software.
Results. The EWOCS X-ray catalog comprises 5963 validated sources out of the 9420 initially provided to ACIS-Extract, reaching a
photon flux threshold of approximately 2 × 10−8 photons cm−2
s
−1
. The X-ray sources exhibit a highly concentrated spatial distribution,
with 1075 sources located within the central 1 arcmin. We have successfully detected X-ray emissions from 126 out of the 166 known
massive stars of the cluster, and we have collected over 71 000 photons from the magnetar CXO J164710.20-455217.
waterlessdyeingtechnolgyusing carbon dioxide chemicalspdf
The technology uses reclaimed CO₂ as the dyeing medium in a closed loop process. When pressurized, CO₂ becomes supercritical (SC-CO₂). In this state CO₂ has a very high solvent power, allowing the dye to dissolve easily.
8.Isolation of pure cultures and preservation of cultures.pdf
Isolation of pure culture, its various method.
THEMATIC APPERCEPTION TEST(TAT) cognitive abilities, creativity, and critic...
THEMATIC APPERCEPTION TEST(TAT) cognitive abilities, creativity, and critic...Abdul Wali Khan University Mardan,kP,Pakistan
hematic appreciation test is a psychological assessment tool used to measure an individual's appreciation and understanding of specific themes or topics. This test helps to evaluate an individual's ability to connect different ideas and concepts within a given theme, as well as their overall comprehension and interpretation skills. The results of the test can provide valuable insights into an individual's cognitive abilities, creativity, and critical thinking skillsPests of Storage_Identification_Dr.UPR.pdf
InIndia-post-harvestlosses-unscientificstorage,insects,rodents,micro-organismsetc.,accountforabout10percentoftotalfoodgrains
Graininfestation
Directdamage
Indirectly
•theexuviae,skin,deadinsects
•theirexcretawhichmakefoodunfitforhumanconsumption
About600speciesofinsectshavebeenassociatedwithstoredgrainproducts
100speciesofinsectpestsofstoredproductscauseeconomiclosses
The cost of acquiring information by natural selection
This is a short talk that I gave at the Banff International Research Station workshop on Modeling and Theory in Population Biology. The idea is to try to understand how the burden of natural selection relates to the amount of information that selection puts into the genome.
It's based on the first part of this research paper:
The cost of information acquisition by natural selection
Ryan Seamus McGee, Olivia Kosterlitz, Artem Kaznatcheev, Benjamin Kerr, Carl T. Bergstrom
bioRxiv 2022.07.02.498577; doi: https://doi.org/10.1101/2022.07.02.498577
Micronuclei test.M.sc.zoology.fisheries.
Current Ms word generated power point presentation covers major details about the micronuclei test. It's significance and assays to conduct it. It is used to detect the micronuclei formation inside the cells of nearly every multicellular organism. It's formation takes place during chromosomal sepration at metaphase.
在线办理(salfor毕业证书)索尔福德大学毕业证毕业完成信一模一样
学校原件一模一样【微信：741003700 】《(salfor毕业证书)索尔福德大学毕业证》【微信：741003700 】学位证，留信认证（真实可查，永久存档）原件一模一样纸张工艺/offer、雅思、外壳等材料/诚信可靠,可直接看成品样本，帮您解决无法毕业带来的各种难题！外壳，原版制作，诚信可靠，可直接看成品样本。行业标杆！精益求精，诚心合作，真诚制作！多年品质 ,按需精细制作，24小时接单,全套进口原装设备。十五年致力于帮助留学生解决难题，包您满意。
本公司拥有海外各大学样板无数，能完美还原。
1:1完美还原海外各大学毕业材料上的工艺：水印，阴影底纹，钢印LOGO烫金烫银，LOGO烫金烫银复合重叠。文字图案浮雕、激光镭射、紫外荧光、温感、复印防伪等防伪工艺。材料咨询办理、认证咨询办理请加学历顾问Q/微741003700
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一.毕业证【q微741003700】成绩单、使馆认证、教育部认证、雅思托福成绩单、学生卡等！
二.真实使馆公证(即留学回国人员证明,不成功不收费)
三.真实教育部学历学位认证（教育部存档！教育部留服网站永久可查）
四.办理各国各大学文凭(一对一专业服务,可全程监控跟踪进度)
如果您处于以下几种情况：
◇在校期间，因各种原因未能顺利毕业……拿不到官方毕业证【q/微741003700】
◇面对父母的压力，希望尽快拿到；
◇不清楚认证流程以及材料该如何准备；
◇回国时间很长，忘记办理；
◇回国马上就要找工作，办给用人单位看；
◇企事业单位必须要求办理的
◇需要报考公务员、购买免税车、落转户口
◇申请留学生创业基金
留信网认证的作用:
1:该专业认证可证明留学生真实身份
2:同时对留学生所学专业登记给予评定
3:国家专业人才认证中心颁发入库证书
4:这个认证书并且可以归档倒地方
5:凡事获得留信网入网的信息将会逐步更新到个人身份内，将在公安局网内查询个人身份证信息后，同步读取人才网入库信息
6:个人职称评审加20分
7:个人信誉贷款加10分
8:在国家人才网主办的国家网络招聘大会中纳入资料，供国家高端企业选择人才
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.Equivariant neural networks and representation theory
Or: Beyond linear.
Abstract: Equivariant neural networks are neural networks that incorporate symmetries. The nonlinear activation functions in these networks result in interesting nonlinear equivariant maps between simple representations, and motivate the key player of this talk: piecewise linear representation theory.
Disclaimer: No one is perfect, so please mind that there might be mistakes and typos.
dtubbenhauer@gmail.com
Corrected slides: dtubbenhauer.com/talks.html
Shallowest Oil Discovery of Turkiye.pptx
The Petroleum System of the Çukurova Field - the Shallowest Oil Discovery of Türkiye, Adana
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.
Sharlene Leurig - Enabling Onsite Water Use with Net Zero Water
Sharlene Leurig - Enabling Onsite Water Use with Net Zero WaterTexas Alliance of Groundwater Districts
Presented at June 6-7 Texas Alliance of Groundwater Districts Business MeetingRecently uploaded (20)
Describing and Interpreting an Immersive Learning Case with the Immersion Cub...
Describing and Interpreting an Immersive Learning Case with the Immersion Cub...
Mending Clothing to Support Sustainable Fashion_CIMaR 2024.pdf
Mending Clothing to Support Sustainable Fashion_CIMaR 2024.pdf
20240520 Planning a Circuit Simulator in JavaScript.pptx
20240520 Planning a Circuit Simulator in JavaScript.pptx
Basics of crystallography, crystal systems, classes and different forms
Basics of crystallography, crystal systems, classes and different forms
Immersive Learning That Works: Research Grounding and Paths Forward
Immersive Learning That Works: Research Grounding and Paths Forward
EWOCS-I: The catalog of X-ray sources in Westerlund 1 from the Extended Weste...
EWOCS-I: The catalog of X-ray sources in Westerlund 1 from the Extended Weste...
waterlessdyeingtechnolgyusing carbon dioxide chemicalspdf
waterlessdyeingtechnolgyusing carbon dioxide chemicalspdf
8.Isolation of pure cultures and preservation of cultures.pdf
8.Isolation of pure cultures and preservation of cultures.pdf
THEMATIC APPERCEPTION TEST(TAT) cognitive abilities, creativity, and critic...
THEMATIC APPERCEPTION TEST(TAT) cognitive abilities, creativity, and critic...
The cost of acquiring information by natural selection
The cost of acquiring information by natural selection
ESA/ACT Science Coffee: Diego Blas - Gravitational wave detection with orbita...
ESA/ACT Science Coffee: Diego Blas - Gravitational wave detection with orbita...
Equivariant neural networks and representation theory
Equivariant neural networks and representation theory
Sharlene Leurig - Enabling Onsite Water Use with Net Zero Water
Sharlene Leurig - Enabling Onsite Water Use with Net Zero Water
Galaxy
- 1. LUMINOSITY FUNCTION OF GALAXIES GALAXY FORMATION AND EVOLUTION 1 BINGELLI, SANDAGE & TAMMANN, 1988
- 2. LUMINOSITY FUNCTION OF GALAXIES ▸ LF: # Galaxies in mag. interval of (M , M+dM) ▸ Mean LF: Sum over all types in a cluster or field region ▸ Specific LF: Sum over each Hubble type ▸ Density function: # galaxies in a point of space ▸ Universal LF: Wrong assumption of constant density, only possible in large enough scales SOME DEFINITIONS … 2
- 3. HISTORY 3
- 4. LUMINOSITY FUNCTION OF GALAXIES WHY DO WE NEED LF ?! ▸ All we have is luminosity! ▸ Spacial distribution ▸ Geometry of the Universe (Practical Cosmology) ▸ Test for formation scenarios: Biased galaxy formation: Dwarfs only as satellites of Giants Dwarfs/Giant will be independent of environment as well as LF 4
- 5. LUMINOSITY FUNCTION OF GALAXIES ▸ Disk galaxies: Baryonic Mass/Luminosity <-> Velocity/Emission Line width ▸ Measuring LF -> Test Tully-Fisher TULLY-FISHER RELATION ref: Wikipedia 5
- 6. LUMINOSITY FUNCTION OF GALAXIES DYNAMICAL FRICTION ▸ Drag force -> interaction of Gs ▸ No interaction -> Static Density ▸ Happy -> Universal LF ! But ▸ Dynamical friction -> evolution of Gs ▸ Loosing J -> sinking toward center ▸ Variation in LF from: Cluster to cluster, throughout a cluster ref: Aaron T. Lee, Steven W. Stahler, 2011 6
- 7. LUMINOSITY FUNCTION OF GALAXIES GALAXY TYPE AND LF ▸ Early types (E, S0, dE)-> higher LF in Clusters ▸ Spirals-> similar in fields and clusters ▸ Early types-> rare in fields ▸ Early types more common in clusters -> higher LF contribution 7 ref: BINGELLI, SANDAGE & TAMMANN, 1988
- 8. THANKS FOR YOUR ATTENTION! San Esteban (Chile): Abell 1060, Hydra I