Searching for Emission from the Warm-Hot Intergalactic Medium
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Cfa in the News ~ Week Ending 3 January 2010
Wolbach Library: CfA in the News ~ Week ending 3 January 2010 1. New social science research from G. Sonnert and co-researchers described, Science Letter, p40, Tuesday, January 5, 2010 2. 2009 in science and medicine, ROGER SCHLUETER, Belleville News Democrat (IL), Sunday, January 3, 2010 3. 'Science, celestial bodies have always inspired humankind', Staff Correspondent, Hindu (India), Tuesday, December 29, 2009 4. Why is Carpenter defending scientists?, The Morning Call, Morning Call (Allentown, PA), FIRST ed, pA25, Sunday, December 27, 2009 5. CORRECTIONS, OPINION BY RYAN FINLEY, ARIZONA DAILY STAR, Arizona Daily Star (AZ), FINAL ed, pA2, Saturday, December 19, 2009 6. We see a 'Super-Earth', TOM BEAL; TOM BEAL, ARIZONA DAILY STAR, Arizona Daily Star, (AZ), FINAL ed, pA1, Thursday, December 17, 2009 Record - 1 DIALOG(R) New social science research from G. Sonnert and co-researchers described, Science Letter, p40, Tuesday, January 5, 2010 TEXT: "In this paper we report on testing the 'rolen model' and 'opportunity-structure' hypotheses about the parents whom scientists mentioned as career influencers. According to the role-model hypothesis, the gender match between scientist and influencer is paramount (for example, women scientists would disproportionately often mention their mothers as career influencers)," scientists writing in the journal Social Studies of Science report (see also ). "According to the opportunity-structure hypothesis, the parent's educational level predicts his/her probability of being mentioned as a career influencer (that ism parents with higher educational levels would be more likely to be named). The examination of a sample of American scientists who had received prestigious postdoctoral fellowships resulted in rejecting the role-model hypothesis and corroborating the opportunity-structure hypothesis. -
Glossary of Terms Absorption Line a Dark Line at a Particular Wavelength Superimposed Upon a Bright, Continuous Spectrum
Glossary of terms absorption line A dark line at a particular wavelength superimposed upon a bright, continuous spectrum. Such a spectral line can be formed when electromag- netic radiation, while travelling on its way to an observer, meets a substance; if that substance can absorb energy at that particular wavelength then the observer sees an absorption line. Compare with emission line. accretion disk A disk of gas or dust orbiting a massive object such as a star, a stellar-mass black hole or an active galactic nucleus. An accretion disk plays an important role in the formation of a planetary system around a young star. An accretion disk around a supermassive black hole is thought to be the key mecha- nism powering an active galactic nucleus. active galactic nucleus (agn) A compact region at the center of a galaxy that emits vast amounts of electromagnetic radiation and fast-moving jets of particles; an agn can outshine the rest of the galaxy despite being hardly larger in volume than the Solar System. Various classes of agn exist, including quasars and Seyfert galaxies, but in each case the energy is believed to be generated as matter accretes onto a supermassive black hole. adaptive optics A technique used by large ground-based optical telescopes to remove the blurring affects caused by Earth’s atmosphere. Light from a guide star is used as a calibration source; a complicated system of software and hardware then deforms a small mirror to correct for atmospheric distortions. The mirror shape changes more quickly than the atmosphere itself fluctuates. -
X-Ray Absorption by the Warm-Hot Intergalactic
Draft version January 13, 2014 A Preprint typeset using LTEX style emulateapj v. 5/2/11 X-RAY ABSORPTION BY THE WARM-HOT INTERGALACTIC MEDIUM IN THE HERCULES SUPERCLUSTER Bin Ren1,2, Taotao Fang1,3, David A. Buote3 (Received; Revised; Accepted) Draft version January 13, 2014 ABSTRACT The “missing baryons”, in the form of warm-hot intergalactic medium (WHIM), are expected to reside in cosmic filamentary structures that can be traced by signposts such as large-scale galaxy superstructures. The clear detection of an X-ray absorption line in the Sculptor Wall demonstrated the success of using galaxy superstructures as a signpost to search for the WHIM. Here we present an XMM-Newton Reflection Grating Spectrometer (RGS) observation of the blazar Mkn 501, located in the Hercules Supercluster. We detected an O VII Kα absorption line at the 98.7% level (2.5σ) at the redshift of the foreground Hercules Supercluster. The derived properties of the absorber are consistent with theoretical expectations of the WHIM. We discuss the implication of our detection for the search for the “missing baryons”. While this detection shows again that using signposts is a very effective strategy to search for the WHIM, follow-up observations are crucial both to strengthen the statistical significance of the detection and to rule out other interpretations. A local, z ∼ 0 O VII Kα absorption line was also clearly detected at the 4σ level, and we discuss its implications for our understanding of the hot gas content of our Galaxy. Subject headings: BL Lacertae objects: individual (Markarian 501) — cosmology: observations — diffuse radiation — X-rays: diffuse background — X-rays: galaxies: clusters 1. -
Observational Cosmology - 30H Course 218.163.109.230 Et Al
Observational cosmology - 30h course 218.163.109.230 et al. (2004–2014) PDF generated using the open source mwlib toolkit. See http://code.pediapress.com/ for more information. PDF generated at: Thu, 31 Oct 2013 03:42:03 UTC Contents Articles Observational cosmology 1 Observations: expansion, nucleosynthesis, CMB 5 Redshift 5 Hubble's law 19 Metric expansion of space 29 Big Bang nucleosynthesis 41 Cosmic microwave background 47 Hot big bang model 58 Friedmann equations 58 Friedmann–Lemaître–Robertson–Walker metric 62 Distance measures (cosmology) 68 Observations: up to 10 Gpc/h 71 Observable universe 71 Structure formation 82 Galaxy formation and evolution 88 Quasar 93 Active galactic nucleus 99 Galaxy filament 106 Phenomenological model: LambdaCDM + MOND 111 Lambda-CDM model 111 Inflation (cosmology) 116 Modified Newtonian dynamics 129 Towards a physical model 137 Shape of the universe 137 Inhomogeneous cosmology 143 Back-reaction 144 References Article Sources and Contributors 145 Image Sources, Licenses and Contributors 148 Article Licenses License 150 Observational cosmology 1 Observational cosmology Observational cosmology is the study of the structure, the evolution and the origin of the universe through observation, using instruments such as telescopes and cosmic ray detectors. Early observations The science of physical cosmology as it is practiced today had its subject material defined in the years following the Shapley-Curtis debate when it was determined that the universe had a larger scale than the Milky Way galaxy. This was precipitated by observations that established the size and the dynamics of the cosmos that could be explained by Einstein's General Theory of Relativity. -
The Hidden Universe: Dark Energy, Dark Matter, and Baryons
The Hidden Universe: Dark Energy, Dark Matter, and Baryons Dissertation Presented in Partial Fulfillment of the Requirements for the Degree Doctor of Philosophy in the Graduate School of The Ohio State University By Joseph Eugene McEwen, B.S., M.S. Graduate Program in Department of Physics The Ohio State University 2016 Dissertation Committee: David H. Weinberg, Advisor Christopher M. Hirata Amy Connolly Stuart Raby c Copyright by Joseph Eugene McEwen 2016 Abstract The universe is dominated by unknown elements, dark energy and dark matter. The mysterious nature of the universe is not limited to the dark components. The present day census of ordinary matter (baryons) in the universe is incomplete. This thesis present the work I have done to uncover the nature of dark energy and dark matter as well as understanding the baryon content in the local universe. Chapter 2 presents an analysis of the baryon content in the local universe as traced by X- ray absorption systems. Chapter 3 present the effects of streaming velocities on the baryon acoustic oscillation scale. Chapter 4 is introduces a new galaxy bias model, the environment dependent halo occupation distribution model. Chapter 5 presents a unique algorithm to compute convolution integrals in cosmological perturbation theory. ii to Billyelou iii Acknowledgments Attending a CCAPP seminar in the summer of 2013 I came to an opinion on the skills possessed by astrophysicists. From my perspective, I saw that astrophysicists had mastered a very broad range of physics, from the smallest scales of atomic physics to the largest scales in cosmology. Not only were astrophysicists knowledgable of many scales of physics, they had a keen sense of physical process. -
QUANTUM GRAVITY and the ROLE of CONSCIOUSNESS in PHYSICS Resolving the Contradictions Between Quantum Mechanics and Relativity
1 QUANTUM CONSCIOUSNESS RESEARCH LIMITED QUANTUM GRAVITY and the ROLE of CONSCIOUSNESS in PHYSICS Resolving the contradictions between quantum mechanics and relativity Sky Darmos 2020/8/14 Explains/resolves accelerated expansion, quantum entanglement, information paradox, flatness problem, consciousness, non-Copernican structures, quasicrystals, dark matter, the nature of quantum spin, weakness of gravity, arrow of time, vacuum paradox, and much more. 2 Working titles: Physics of the Mind (2003 - 2006); The Conscious Universe (2013 - 2014). Presented theories (created and developed by Sky Darmos): Similar-worlds interpretation (2003); Space particle dualism theory* (2005); Conscious set theory (2004) (Created by the author independently but fundamentally dependent upon each other). *Inspired by Roger Penrose’s twistor theory (1967). Old names of these theories: Equivalence theory (2003); Discontinuity theory (2005); Relationism (2004). Contact information: Facebook: Sky Darmos WeChat: Sky_Darmos Email: [email protected] Cover design: Sky Darmos (2005) Its meaning: The German word “Elementarräume”, meaning elementary spaces, is written in graffiti style. The blue background looks like a 2-dimensional surface, but when we look at it through the two magnifying glasses at the bottom we see that it consists of 1-dimensional elementary “spaces” (circles). That is expressing the idea that our well known 3-dimensional space could in the same way be made of 2- dimensional sphere surfaces. The play with dimensionality is further extended by letting all the letters approach from a distant background where they appear as a single point (or point particle) moving through the pattern formed by these overlapping elementary spaces. The many circles originating from all angles in the letters represent the idea that every point (particle) gives rise to another elementary space (circle). -
Large-Scale Structures in Three Dimensions
67 LARGE-SCALE STRUCTURES IN THREE DIMENSIONS A.P. Fairall and W.R. Paverd Departments of Astronomy and Computer Science, University of Cape To wn, Rondebosch, 7700 South Africa. Abstract Three-dimensional views are used to explore the character of the large-scale distri bution of southern galaxies. They show that within great walls of galaxies, such as the Sculptor great wall, there exists a cellular texture with voids smaller in size than 1000 km s-1 (whereas the voids that separate great walls are of order 5000 km s-1) in redshift space. The view from the position of our own galaxy reveals that the concentration of galaxies forming the supergalactic equator is spread in depth from the nearest galaxies out to approximately cz= 10000 km s-1, with many small voids embedded. It is therefore suggested that our galaxy is itself within a (Centaurus) great wall structure. 1 Introduction Our contribution at the Rencontres de Moriond consisted of the presentation of a sequence of images, showing galaxies as colour-coded dots against a black background. The audience was equipped with ChromoDepth(tm) spectacles, that translate colour into stereoscopic depth, thereby enabling the audience to view the structures in three dimensions (3D). A colour-coded video was also shown. Regrettably, there is no way that the 3D images can be successfully reproduced here with this article. The text and diagrams following give brief descriptions of the images, and convey the verbal information that accompanied the presentation. 68 · ··:�· ..� � : � ·... ,,.·. '· ·-:.: ·.�·:: .',;�/··',)i:f<: ,, .• . > :r' . -�· : . ·� . ::- .. : �· . :.· Figure 1: A projection of the distribution of galaxies in the Sculptor (top), Fornax (bottom) and Grus (vertical centre) Walls. -
DSSU Validated by Redshift Theory and Structural Evidence Conrad Ranzan * DSSU Research, Niagara Falls, Canada, L2E 4J8
DSSU Validated by Redshift Theory and Structural Evidence Conrad Ranzan * DSSU Research, Niagara Falls, Canada, L2E 4J8 Reprint of the article published in Physics Essays , Vol. 28 , No.4, pp455-473 (2015) (Submitted 2015-6-1; accepted 2015-9-15) © 2015 copyright Physics Essays Publication (Journal website: http://physicsessays.org) Contents 1. Heart of Modern Cosmology .......................................................................................................................... 2 1.1 Twentieth-Century Developments ........................................................................................................... 2 1.2 The Pillar of Twentieth-Century Cosmology ........................................................................................ 3 2. The Overlooked Cosmic Redshift Mechanism ....................................................................................... 4 2.1 Nature of Space ................................................................................................................................................. 4 2.2 Cosmic Cell ........................................................................................................................................................... 4 2.3 Redshift Acquisition Within Contractile Zone ...................................................................................... 4 2.4 Redshift Acquisition Within Expansion Zone ........................................................................................ 6 2.5 Redshift Acquisition During -
Science Olympiad Astronomy C Division Event 2020 Astronomy Test
Science Olympiad Astronomy C Division Event 2020 Astronomy Test NASA Universe of Learning May 15, 2020 Instructions: 1) Please turn in all materials at the end of the event. 2) Do not forget to put your team name and team number at the top of all answer pages. 3) Write all answers on the lines on the answer pages. Any marks elsewhere will not be scored. 4) Do not worry about significant figures. Use 3 or more in your answers, regardless of how many are in the question. 5) Usually, we would say please do not access the internet during the event. However, you will need to in order to answer Question #21. 6) Feel free to take apart the test and staple it back together at the end! 7) Good luck! And may the stars be with you! 1 Section A: Use the Image/Illustration Set to answer the following questions. Each question or sub-question in this section is worth one point. 1. (a) What NASA mission resulted in the map shown in image 32? (b) What type of radiation is being shown? (c) What theory did the results of this mission and radiation map confirm? 2. (a) What is the name and the numbers of the 2 Hubble images that show the furthest Type Ia supernova observed to date? (b) What is the number and letter of the image that shows the energy emitted from this type of event? 3. (a) What is the name and specific type of the object in image 3? (b) The concurrent observational data from two missions were combined to produce this image. -
X-Ray Absorption by the Warm-Hot Intergalactic Medium in The
Draft version August 6, 2018 A Preprint typeset using LTEX style emulateapj v. 5/2/11 X-RAY ABSORPTION BY THE WARM-HOT INTERGALACTIC MEDIUM IN THE HERCULES SUPERCLUSTER Bin Ren1,2, Taotao Fang1,3, David A. Buote3 (Received; Revised; Accepted) Draft version August 6, 2018 ABSTRACT The “missing baryons”, in the form of warm-hot intergalactic medium (WHIM), are expected to reside in cosmic filamentary structures that can be traced by signposts such as large-scale galaxy superstructures. The clear detection of an X-ray absorption line in the Sculptor Wall demonstrated the success of using galaxy superstructures as a signpost to search for the WHIM. Here we present an XMM-Newton Reflection Grating Spectrometer (RGS) observation of the blazar Mkn 501, located in the Hercules Supercluster. We detected an O VII Kα absorption line at the 98.7% level (2.5σ) at the redshift of the foreground Hercules Supercluster. The derived properties of the absorber are consistent with theoretical expectations of the WHIM. We discuss the implication of our detection for the search for the “missing baryons”. While this detection shows again that using signposts is a very effective strategy to search for the WHIM, follow-up observations are crucial both to strengthen the statistical significance of the detection and to rule out other interpretations. A local, z ∼ 0 O VII Kα absorption line was also clearly detected at the 4σ level, and we discuss its implications for our understanding of the hot gas content of our Galaxy. Subject headings: BL Lacertae objects: individual (Markarian 501) — cosmology: observations — diffuse radiation — X-rays: diffuse background — X-rays: galaxies: clusters 1. -
A Galaxisok Világa Tóth L
A galaxisok világa Tóth L. Viktor XML to PDF by RenderX XEP XSL-FO F ormatter, visit us at http://www.renderx.com/ A galaxisok világa Tóth L. Viktor Szerzői jog © 2013 Eötvös Loránd Tudományegyetem E könyv kutatási és oktatási célokra szabadon használható. Bármilyen formában való sokszorosítása a jogtulajdonos írásos engedélyéhez kötött. Készült a TÁMOP-4.1.2.A/1-11/1-2011-0073 számú, „E-learning természettudományos tartalomfejlesztés az ELTE TTK-n” című projekt keretében. Konzorciumvezető: Eötvös Loránd Tudományegyetem, konzorciumi tagok: ELTE TTK Hallgatói Alapítvány, ITStudy Hungary Számítástechnikai Oktató- és Kutatóközpont Kft. XML to PDF by RenderX XEP XSL-FO F ormatter, visit us at http://www.renderx.com/ Tartalom Előszó ........................................................................................................................................ vii 1. Bevezetés .................................................................................................................................. 1 1.1 Ködök ............................................................................................................................. 1 1.2. Világmodellek – a Shapley-Curtis vita ................................................................................. 4 1.2.1. A Shapley-Curtis vita főbb kérdései: ......................................................................... 5 1.2.2. A Shapley-Curtis vita tudományos előzményei és háttere: ............................................. 5 Referenciák és további olvasnivaló az előszó -
Astronautics and Aeronautics, 2010
National Aeronautics and Space Administration ASTRONAUTICS AND AERONAUTICS, 2010 A CHRONOLOGY www.nasa.gov SP-2013-4037 AERONAUTICS AND ASTRONAUTICS: A CHRONOLOGY: 2010 NASA SP-2014-4037 September 2013 Author: Meaghan Flattery Project Manager: Alice R. Buchalter Federal Research Division, Library of Congress NASA History Program Office Public Outreach Division Office of Communications NASA Headquarters Washington, DC 20546 Aeronautics and Astronautics: A Chronology, 2010 PREFACE This report is a chronological compilation of narrative summaries of news reports and government documents highlighting significant events and developments in U.S. and foreign aeronautics and astronautics. It covers the year 2010. These summaries provide a day-to-day recounting of major activities, such as administrative developments, Congressional hearings, awards, launches, scientific discoveries, corporate and government research results, and other events in countries with aeronautics and astronautics programs. Researchers used the archives and files housed in the NASA History Program Office, as well as reports and databases on the NASA Web site and the Web sites of select non–U.S. space agencies. Researchers also accessed the Web sites of various federal government agencies and those of congressional committees with jurisdiction over science, aeronautics, and space programs. i Aeronautics and Astronautics: A Chronology, 2010 TABLE OF CONTENTS PREFACE.................................................................................................................................