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2013 January/February AAS Newsletter 31 January, 2013
2013 January/February AAS Newsletter 31 January, 2013 President's Column David J. Helfand Quest University Canada As I noted in my opening remarks at the 221st meeting of the Society in Long Beach, the state of the AAS — unlike that of the nation — is strong. We ended the year with a small positive balance in the Society's account for the fourth year in a row. Our collection of journals — the highest impact journals in the world in our field — is in even stronger financial shape. Our semiannual conferences exceed expected attendance levels every time we meet, and we are exploiting the Executive Office's outstanding meeting organization resources to support more of our Division Meetings and to launch the Topical Conference Series with three smaller, focused meetings this summer. We will have an expanded public policy presence with the recruitment of Joel Parriott to the fulltime role of Director of Public Policy, and our education and public outreach activities continue to grow in size and impact. This enviable position of strength affords us the opportunity to examine many of the things we do for our members to see if we can do them even better. It also allows us to work on some of the issues in our discipline where we face notable challenges in the research funding trajectory, in facilities access, and with employment/demographic issues. In the months ahead, you will see initiatives in several of these areas. The Employment Committee, chaired by Kelle Cruz, has a new Strategic Plan which promises future benefits for our members. -
Cosmic Background Explorer (COBE) and Beyond
From the Big Bang to the Nobel Prize: Cosmic Background Explorer (COBE) and Beyond Goddard Space Flight Center Lecture John Mather Nov. 21, 2006 Astronomical Search For Origins First Galaxies Big Bang Life Galaxies Evolve Planets Stars Looking Back in Time Measuring Distance This technique enables measurement of enormous distances Astronomer's Toolbox #2: Doppler Shift - Light Atoms emit light at discrete wavelengths that can be seen with a spectroscope This “line spectrum” identifies the atom and its velocity Galaxies attract each other, so the expansion should be slowing down -- Right?? To tell, we need to compare the velocity we measure on nearby galaxies to ones at very high redshift. In other words, we need to extend Hubble’s velocity vs distance plot to much greater distances. Nobel Prize Press Release The Royal Swedish Academy of Sciences has decided to award the Nobel Prize in Physics for 2006 jointly to John C. Mather, NASA Goddard Space Flight Center, Greenbelt, MD, USA, and George F. Smoot, University of California, Berkeley, CA, USA "for their discovery of the blackbody form and anisotropy of the cosmic microwave background radiation". The Power of Thought Georges Lemaitre & Albert Einstein George Gamow Robert Herman & Ralph Alpher Rashid Sunyaev Jim Peebles Power of Hardware - CMB Spectrum Paul Richards Mike Werner David Woody Frank Low Herb Gush Rai Weiss Brief COBE History • 1965, CMB announced - Penzias & Wilson; Dicke, Peebles, Roll, & Wilkinson • 1974, NASA AO for Explorers: ~ 150 proposals, including: – JPL anisotropy proposal (Gulkis, Janssen…) – Berkeley anisotropy proposal (Alvarez, Smoot…) – Goddard/MIT/Princeton COBE proposal (Hauser, Mather, Muehlner, Silverberg, Thaddeus, Weiss, Wilkinson) COBE History (2) • 1976, Mission Definition Science Team selected by HQ (Nancy Boggess, Program Scientist); PI’s chosen • ~ 1979, decision to build COBE in-house at GSFC • 1982, approval to construct for flight • 1986, Challenger explosion, start COBE redesign for Delta launch • 1989, Nov. -
Viktor Ambartsumian International Prize 2012 Goes to Prof. Jaan EINASTO (Estonia) and Prof
Viktor Ambartsumian International Prize Steering Committee Official Press-Release, 21.07.2012, Yerevan, Armenia Viktor Ambartsumian International Prize 2012 goes to Prof. Jaan EINASTO (Estonia) and Prof. Igor NOVIKOV (Russia) Viktor Ambartsumian International Prize has been established by the President of Armenia in 2009 and at present is one of the important awards in astronomy/astrophysics and related sciences. It is being awarded to outstanding scientists from any country and nationality having significant contribution in science. The Prize totals USD 500,000 and since 2010 is being awarded once every two years. March 18 was the deadline for nominations, and the International Steering Committee chaired by the President of the Armenian National Academy of Sciences Prof. Radik Martirosyan received nominations from national academies of sciences, universities, observatories, and Nobel Prize winners for 12 outstanding scientists and teams from different countries. After a thorough study of the nominated works, as well as independent referees’ reports, the Committee had several discussions and finally it was decided to share the Prize between Prof. Jaan Einasto (Tartu Observatory, Estonia), nominated by Tartu Observatory “for his fundamental contributions to the discovery of dark matter and the cosmic web” and Prof. Igor Novikov (Astro-Space Center, P.N. Lebedev Physics Institute, Russia) nominated by the Institute of Theoretical Physics and Astronomy of Vilnius University, Lithuania “for his pioneering formulation how to confirm observationally that our Universe started as a hot one, and for proposing the method for determination of quasar masses”. Jaan Einasto (83) is a senior scientist at the Tartu Observatory, Estonia. Since 1952 he works at Tartu Observatory. -
Sandra Faber Receives $500,000 Gruber Cosmology Prize
Media Contact: A. Sarah Hreha +1 (203) 432-6231 [email protected] Online Newsroom: www.gruber.yale.edu/news-media SANDRA FABER RECEIVES $500,000 GRUBER COSMOLOGY PRIZE FOR CAREER ACHIEVEMENTS Sandra Faber May 17, 2017, New Haven, CT – The 2017 Gruber Foundation Cosmology Prize recognizes Sandra M. Faber for a body of work that has helped establish many of the foundational principles underlying the modern understanding of the universe on the largest scales. The citation praises Faber for “her groundbreaking studies of the structure, dynamics, and evolution of galaxies.” That work has led to the widespread acceptance of the need to study dark matter, to an appreciation of the inextricable relationship between the presence of dark matter and the formation of galaxies, and to the recognition that black holes reside at the heart of most large galaxies. She has also made significant contributions to the innovations in telescope technology that have revolutionized modern astronomy. Through these myriad achievements, the Gruber citation adds, Faber has “aided and inspired the work of astronomers and cosmologists worldwide.” Faber will receive the $500,000 award as well as a gold medal at a ceremony this fall. Less than a hundred years ago, astronomers were still debating whether our Milky Way Galaxy was the entirety of the universe or if other galaxies existed beyond our own. Today astronomers estimate the number of galaxies within the visible universe at somewhere between 200 billion and 2 trillion. For more than four decades Faber—now Professor Emerita at the University of California, Santa Cruz, and Astronomer Emerita of the University of California Observatories—has served as a pivotal figure in leading and guiding the exploration of this unimaginably vast virgin scientific territory. -
Icranet Scientific Report 2009
Cosmology group of Tartu Observatory 1 The cosmology group of Tartu Observatory 1.1 Science staff members Jaan Einasto, Maret Einasto, Mirt Gramann, Urmas Haud, Gert Hutsi, Juhan Lauri Liivamägi, Valery Malyuto; Enn Saar, Ivan Suhhonenko, Erik Tago, Antti Tamm, Elmo Tempel, Peeter Tenjes, Jaan Vennik; 1.2 PhD student Tiit Sepp 1.3 Technicians Peeter Einasto, Triin Einasto, Margus Sisask. 1527 2 Scientific studies I will classify the results according to the project goals. 2.1 Testing the inflationary paradigm In order to test the inflationary paradigm (the initial extremely fast expansion of the Universe) we studied the observational traces of baryon oscillations (BAO), predicted by inflation theories. Gert Hütsi discovered the traces of BAO in the power spectrum of the galaxy distribution, using the catalogue of the distant galaxy clusters of the Sloan Digital Sky Survey (SDSS). The paper has been accepted by ’Monthly Notices of the Royal Astronomical Society’ (MNRAS). Enn Saar, together with Ivan Suhhonenko and colleagues from the Valen- cia and Tuorla observatories demonstrated that photometric redshifts can be used to restore the matter correlation functions of deep lightcones. The paper has been published by MNRAS. Gert Hütsi, together with colleagues from the Hiroshima University, stud- ied the damping of BAO, and estimated the structure growth rate. One paper has been published (Physical Review), another submitted. Traces of BAO can be sought also in the correlation function of galaxies. Enn Saar and Elmo Tempel, together with colleagues from Valencia, found these. Enn Saar also solved the problem of bootstrap estimation of correlation function errors. The paper was published in ’Astrophysical Journal Letters’. -
Lars Hernquist and Volker Springel Receive $500,000 Gruber Cosmology Prize
Media Contact: A. Sarah Hreha +1 (203) 432‐6231 [email protected] Online Newsroom: https://gruber.yale.edu/news‐media Lars Hernquist and Volker Springel Receive $500,000 Gruber Cosmology Prize Lars Hernquist Volker Springel New Haven, CT — The 2020 Gruber Cosmology Prize recognizes Lars Hernquist, Center for Astrophysics | Harvard & Smithsonian, and Volker Springel, Max Planck Institute for Astrophysics, for their defining contributions to cosmological simulations, a method that tests existing theories of, and inspires new investigations into, the formation of structures at every scale from stars to galaxies to the universe itself. Hernquist and Springel will divide the $500,000 award, and each will receive a gold laureate pin at a ceremony that will take place later this year. The award recognizes their transformative work on structure formation in the universe, and development of numerical algorithms and community codes further used by many other researchers to significantly advance the field. Hernquist was a pioneer in cosmological simulations when he joined the fledgling field in the late 1980s, and since then he has become one of its most influential figures. Springel, who entered the field in 1998 and first partnered with Hernquist in the early 2000s, has written and applied several of the most widely used codes in cosmological research. Together Hernquist and Springel constitute, in the words of one Gruber Prize nominator, “one of the most productive collaborations ever in cosmology.” Computational simulations in cosmology begin with the traditional source of astronomical data: observations of the universe. Then, through a combination of theory and known physics that might approximate initial conditions, the simulations recreate the subsequent processes that would have led to the current structure. -
Receives Gruber Cosmology Prize at the Max Planck Institute for Extraterrestrial Physics
US Media Contact: Foundation Contact: Cassandra Oryl Bernetia Akin +1 (202) 309-2263 +1 (340) 775-4430 [email protected] [email protected] Online Newsroom: www.gruberprizes.org/Press.php FOR IMMEDIATE RELEASE The “Gang of Four” Receives Gruber Cosmology Prize at the Max Planck Institute for Extraterrestrial Physics October 26, 2011, New York, NY – The 2011 Cosmology Prize of the Gruber Foundation will be presented on October 27, 2011, to four superstars so renowned in their field that they are known to astronomers collectively by the initials of their surnames: DEFW. Also sometimes dubbed "the Gang of Four," Marc Davis, George Efstathiou, Carlos Frenk and Simon White collaborated on studies in the 1980s that changed existing beliefs about the formation of structure in the universe and introduced new ways of probing its secrets. Separately, each has continued to distinguish himself in the ensuing years and all remain at the forefront of the astronomical frontier. The quartet will share equally the $500,000 Prize which will be presented in a ceremony at the Max Planck Institute for Extraterrestrial Physics in Garching, Germany. Immediately afterwards, they will deliver a free, public joint lecture about their groundbreaking findings, "Computer Simulations and the Development of the Cold Dark Matter Cosmology," describing how they used cutting-edge computer technology to develop techniques to simulate how the universe evolved. Their findings established the key role of cold dark matter in the formation of cosmic structures such as galaxies, galaxy clusters and the "cosmic web" of interconnected filamentary structures that permeate the universe. Their results were first published in a series of five landmark papers from 1985 to 1988. -
Annual Report 2013 1 Research
Annual Report 2013 Jaan Einasto 1 Research I participated in the comparison of the structure of groups of galaxies of the Sloan Digital Sky Survey seventh data release (SDSS DR7) galaxy and galaxy group catalogues and groups found for the Millennium N-body simulation by Nurmi et al. (2013). We analysed the group luminosities, group richnesses, virial radii, sizes of groups and their rms velocities for four volume-limited samples from observations and simulations. Our results showed that the spatial densities of groups agree within one order of magnitude in all samples with a rather good agreement between the mock catalogues and observations. I participated in the search for shell-like structures in the distribution of nearby rich clusters of galaxies drawn from the SDSS DR8, initiated by Maret Einasto (Einasto et al., 2013b). We find the maxima in the distribution of distances from rich galaxy clusters to other groups and clusters at distance of about 120 h−1 Mpc suggesting a density enhancement at these distances from rich clusters, and possible indication of shell-like structures. The rich cluster A1795, the central cluster of the Bootes supercluster, has the highest maximum in the distance distribution of other groups and clusters around them at distance of about 120 h−1 Mpc among our rich cluster sample, and another maximum at a distance of about 240 h−1 Mpc. However, the radius of the possible shell is larger than expected for a BAO shell (≈ 109 h−1 Mpc). Together with Maret Einasto and collaborators I studied the morphology and galaxy content of SDSS DR8 superclusters (Einasto et al., 2013a). -
Finding the Radiation from the Big Bang
Finding The Radiation from the Big Bang P. J. E. Peebles and R. B. Partridge January 9, 2007 4. Preface 6. Chapter 1. Introduction 13. Chapter 2. A guide to cosmology 14. The expanding universe 19. The thermal cosmic microwave background radiation 21. What is the universe made of? 26. Chapter 3. Origins of the Cosmology of 1960 27. Nucleosynthesis in a hot big bang 32. Nucleosynthesis in alternative cosmologies 36. Thermal radiation from a bouncing universe 37. Detecting the cosmic microwave background radiation 44. Cosmology in 1960 52. Chapter 4. Cosmology in the 1960s 53. David Hogg: Early Low-Noise and Related Studies at Bell Lab- oratories, Holmdel, N.J. 57. Nick Woolf: Conversations with Dicke 59. George Field: Cyanogen and the CMBR 62. Pat Thaddeus 63. Don Osterbrock: The Helium Content of the Universe 70. Igor Novikov: Cosmology in the Soviet Union in the 1960s 78. Andrei Doroshkevich: Cosmology in the Sixties 1 80. Rashid Sunyaev 81. Arno Penzias: Encountering Cosmology 95. Bob Wilson: Two Astronomical Discoveries 114. Bernard F. Burke: Radio astronomy from first contacts to the CMBR 122. Kenneth C. Turner: Spreading the Word — or How the News Went From Princeton to Holmdel 123. Jim Peebles: How I Learned Physical Cosmology 136. David T. Wilkinson: Measuring the Cosmic Microwave Back- ground Radiation 144. Peter Roll: Recollections of the Second Measurement of the CMBR at Princeton University in 1965 153. Bob Wagoner: An Initial Impact of the CMBR on Nucleosyn- thesis in Big and Little Bangs 157. Martin Rees: Advances in Cosmology and Relativistic Astro- physics 163. -
Numerical Galaxy Formation and Cosmology Simulating the Universe on a Computer
Numerical galaxy formation and cosmology Simulating the universe on a computer Lecture 1: Motivation and Historical Overview Benjamin Moster 1 About this lecture • Lecture slides will be uploaded to www.usm.lmu.de/people/moster/Lectures/NC2018.html • Exercises will be lead by Ulrich Steinwandel and Joseph O’Leary 1st exercise will be next week (18.04.18, 12-14, USM Hörsaal) • Goal of exercises: run your own simulations on your laptop Code: Gadget-2 available at http://www.mpa-garching.mpg.de/gadget/ • Please put your name and email address on the mailing list • Evaluation: - Project with oral presentation (to be chosen individually) - Bonus (up to 0.3) for participating in tutorials and submitting a solution to an exercise sheet (at least 70%) 2 Numerical Galaxy Formation & Cosmology 1 11.04.2018 Literature • Textbooks: - Mo, van den Bosch, White: Galaxy Formation and Evolution, 2010 - Schneider: Extragalactic Astronomy and Cosmology, 2006 - Padmanabhan: Structure Formation in the Universe, 1993 - Hockney, Eastwood: Computer Simulation Using Particles, 1988 • Reviews: - Trenti, Hut: Gravitational N-Body Simulations, 2008 - Dolag: Simulation Techniques for Cosmological Simulations, 2008 - Klypin: Numerical Simulations in Cosmology, 2000 - Bertschinger: Simulations of Structure Formation in the Universe, 1998 3 Numerical Galaxy Formation & Cosmology 1 11.04.2018 Outline of the lecture course • Lecture 1: Motivation & Historical Overview • Lecture 2: Review of Cosmology • Lecture 3: Generating initial conditions • Lecture 4: Gravity algorithms -
Ay 21 - Galaxies and Cosmology Prof
Ay 21 - Galaxies and Cosmology Prof. S. G. Djorgovski Winter 2021 Cosmology* as a Science • A study of the universe as a whole, its global geometry, dynamics, history, fate, and its major constituents - galaxies and large-scale structures, their formation and evolution • A basic assumption: the physical laws are the same at all times and everywhere – Some aspects of this are testable – But a new and unexpected physics can show up, e.g., dark matter, dark energy • Only one object of study, and all we can do is look at the surface of the past light cone • Observations tend to be difficult, and subject to biases and selection effects * From Greek kosmos = order; see also cosmetology … The Evolution of the Cosmological Thought … From magical and arbitrary to rational and scientific Folklore to theology to philosophy to physics … Away from anthropocentric/anthropomorphic The Copernican revolution … From final and static to evolving and open-ended The Darwinian revolution … From absolute certainty to an ever expanding sphere of knowledge and a boundary of unknown Cosmology today is a branch of physics Dust Off Your Astronomical Units! • Distance: – Astronomical unit: the distance from the Earth to the Sun, 1 au = 1.496Í1013 cm – Light year: c Í1 yr, 1 ly = 9.463 Í1017 cm – Parsec: the distance from which 1 au subtends an angle of 1 arcsec, 1 pc = 3.086 Í1018 cm = 3.26 ly = 206,264.8 au • Mass and Luminosity: 33 – Solar mass: 1 M = 1.989 Í10 g 33 – Solar luminosity: 1 L = 3.826Í10 erg/s Fluxes and Magnitudes For historical reasons, fluxes in the optical and IR are measured in magnitudes: m = −2.5log10 F + constant Usually integrated over some finite bandpass, e.g., V band (l ~ 550 nm): € fl mV = −2.5log10 F + constant flux integrated over the range l of wavelengths for this band € If the flux is integrated over the entire spectrum, then m is the bolometric magnitude. -
Brinson Mather 2011.Pptx
From the Big Bang to the Nobel Prize and on to James Webb Space Telescope and the Discovery of Alien Life John C. Mather Senior Project Scientist, James Webb Space Telescope, NASA’s Goddard Space Flight Center Nov. 1, 2011 Nov. 1, 2011 Mather Brinson 2011 1 (as of 1985) 2 Nov. 1, 2011 Mather Brinson 2011 Can you imagine? Your chin is made of exploded stars! Nov. 1, 2011 Mather Brinson 2011 3 Looking Back in Time Nov. 1, 2011 Mather Brinson 2011 4 Measuring Distance This technique enables measurement of enormous distances Nov. 1, 2011 Mather Brinson 2011 5 Astronomer's Toolbox #2: Doppler Shift - Light Atoms emit light at discrete wavelengths that can be seen with a spectroscope This “line spectrum” identifies the atom and its velocity Nov. 1, 2011 Mather Brinson 2011 6 Hubble’s Law – 1929 Data Discovered by Lemaître, 1927! Speed proportional to distance Age = distance/speed Speed --> Nov. 1, 2011 Mather Brinson 2011 Distance --> 7 The Power of Thought Alexander Friedman Georges Lemaître & Albert Einstein George Gamow Robert Herman & Ralph Alpher Rashid Sunyaev Jim Peebles Nov. 1, 2011 Mather Brinson 2011 8 Nov. 1, 2011 Mather Brinson 2011 9 Big Bang - Cosmic Explosion 13.7 billion years ago IMPOSSIBLE TO DRAW A PICTURE! Nov. 1, 2011 Mather Brinson 2011 10 How did a smooth Big Bang make complicated things like us? • Gravity is long range attractive force – Matter distribution is unstable • Remove heat, and system heats up more • Makes condensed objects (stars, galaxies, etc.) • Gravitational energy flows support complexity • Stars release heat from nuclear reactions – Heat & light received by Earth support complexity, from weather to photosynthesis Nov.