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Roger A. Chevalier Curriculum Vitae Address
Roger A. Chevalier Curriculum Vitae Address Department of Astronomy, University of Virginia, P. O. Box 400325, Charlottesville, VA 22904 (434) 924–4889 (office); (434) 924–3104 (fax); [email protected] Education Ph.D. Astronomy, Princeton University, 1973 B.S. Astronomy, California Institute of Technology, 1970 Employment W. H. Vanderbilt Professor of Astronomy, University of Virginia, Charlottesville, VA, 1990– Professor of Astronomy, University of Virginia, 1985–90 Chair, Department of Astronomy, University of Virginia, 1985–88, 1989–92 Associate Professor of Astronomy, University of Virginia, 1979–85 Associate Astronomer, Kitt Peak National Observatory, Tucson, AZ, 1976–79 Assistant Astronomer, Kitt Peak National Observatory, Tucson, AZ, 1973–76 Honors NASA Public Service Group Achievement Award to Supernova Science Team (SN 1987A), 1989 Virginia’s Outstanding Scientist Award, 1991 President’s and Visitors’ Research Prize, University of Virginia, 1992 Dannie Heineman Prize for Astrophysics, 1996 Elected to National Academy of Sciences, 1996 Meeting “A Festival of Cosmic Explosions: Celebrating the Contributions and Ac- complishments of Roger Chevalier” held August 21-23, 2009, Caltech, Pasadena, CA Committees American Astronomical Society: High Energy Astrophysics Division Executive Committee (1985–86); Councilor (1988–91); Heineman Prize Committee (2001– 03; Chair 2003) Associated Universities for Research in Astronomy: Observatories Visiting Com- mittee (1999–2002; Chair 2002) National Science Foundation: Committee on Large Optical/Infrared Telescopes (1985–86); Committee of Visitors, Division of Astronomical Sciences (1990, 1993); Advisory Committee, Division of Astronomical Sciences (1991–93) National Aeronautics and Space Administration: Science Working Group on Su- pernova 1987A (1987–88) National Academy of Sciences/National Research Council: Committee on Space Astronomy and Astrophysics (1987–88); Theory Panel of Astronomy Survey 1 Committee for the 1990’s (1989–90); Committee on Astronomy and Astrophysics (1997–2002); Watson Prize Committee; U.S. -
Globular Clusters and Galactic Nuclei
Scuola di Dottorato “Vito Volterra” Dottorato di Ricerca in Astronomia– XXIV ciclo Globular Clusters and Galactic Nuclei Thesis submitted to obtain the degree of Doctor of Philosophy (“Dottore di Ricerca”) in Astronomy by Alessandra Mastrobuono Battisti Program Coordinator Thesis Advisor Prof. Roberto Capuzzo Dolcetta Prof. Roberto Capuzzo Dolcetta Anno Accademico 2010-2011 ii Abstract Dynamical evolution plays a key role in shaping the current properties of star clus- ters and star cluster systems. We present the study of stellar dynamics both from a theoretical and numerical point of view. In particular we investigate this topic on different astrophysical scales, from the study of the orbital evolution and the mutual interaction of GCs in the Galactic central region to the evolution of GCs in the larger scale galactic potential. Globular Clusters (GCs), very old and massive star clusters, are ideal objects to explore many aspects of stellar dynamics and to investigate the dynamical and evolutionary mechanisms of their host galaxy. Almost every surveyed galaxy of sufficiently large mass has an associated group of GCs, i.e. a Globular Cluster System (GCS). The first part of this Thesis is devoted to the study of the evolution of GCSs in elliptical galaxies. Basing on the hypothesis that the GCS and stellar halo in a galaxy were born at the same time and, so, with the same density distribution, a logical consequence is that the presently observed difference may be due to evolution of the GCS. Actually, in this scenario, GCSs evolve due to various mechanisms, among which dynamical friction and tidal interaction with the galactic field are the most important. -
"Southern Skies and Cosmic Questions" by Ed Bertschinger
Edmund Bertschinger Southern Skies and Cosmic Questions how big is the observable universe? what is it made of? why does space repel itself? n January 2006—the middle of summer in the i Southern hemisphere—a bus full of MIT alumni, family, and friends ascended a narrow, winding dirt road through the coastal range of Chile up to 2400 meters (8000 feet) elevation. After visiting European and American national observatory sites during the preceding days, the group figure 1 Wide-angle view of the Southern sky was eager to see the private observatory of which MIT is a part- taken from the Andes Mountains of Argentina on January 28, 2007. Visible ner: the Magellan Telescopes at Las Campanas Observatory. Only are Comet McNaught, the brightest comet in over 40 years; the splotchy Milky Way; and one traveler in the group had been there before: five years earlier, our two satellite galaxies, the Magellanic Clouds. (Photo credit and copyright: Miloslav Jane Pappalardo had attended the dedication of the newly built Druckmüller) telescopes. The author, serving as a scientific tour guide, was excited to arrive finally at the facility his colleague, MIT Magellan director Prof. Paul Schechter, had helped design and commission. After traveling a week through Northern Chile we had reached the summit of a remarkable trip. C H i L E — a th i n st r i P of L a n d between the Pacific Ocean and the crest of the Andes—is an astronomical mecca. The cold Humboldt ocean current flow- ing northward from Antarctica keeps the marine clouds low against the wall of coastal mountains. -
Curriculum Vitae of Robert J. Scherrer
CURRICULUM VITAE OF ROBERT J. SCHERRER Address: Department of Physics and Astronomy Vanderbilt University Nashville, TN 37235 phone: 615-343-3230/615-343-6419 email: [email protected] Education Sept. 1977 - June 1981: Princeton University, A.B. in physics, magna cum laude Sept. 1981 - Aug. 1983: Cambridge University, M.A. in physics. Sept. 1983 - Oct. 1986: University of Chicago, Ph.D. in physics (Thesis advisor: Prof. Michael S. Turner). Positions Held Oct. 1986 - Jun. 1987, Oct. 1987 - Jul. 1988: Harvard University, Postdoctoral Research Associate. Jun. 1987 - Oct. 1987, Jul. 1988 - Dec. 1988: Queen Mary College, University of London, NATO Postdoctoral Fellow. Jan. 1989 - Sept. 1993: Assistant Professor, Department of Physics, The Ohio State University. Oct. 1993 - Sept. 1998: Associate Professor, Department of Physics, The Ohio State University. Oct. 1996 - Sept. 1998: Associate Professor, Department of Astronomy, The Ohio State University. Sept. 1997 - May 1998: Visiting Scientist, Theoretical Astrophysics Group, Fermilab Oct. 1998 - Aug. 2003: Professor, Department of Physics and Department of Astronomy, The Ohio State University. Oct. 1999 - Aug. 2003: Vice-Chair for Undergraduate Studies, Department of Physics, The Ohio State University Sept. 2003 - present: Professor, Department of Physics and Astronomy, Vanderbilt University. Jan. 2004 - present: Chair, Department of Physics and Astronomy, Vanderbilt University Honors and Awards Marshall Scholarship (1981-83). McCormick Graduate Fellowship (University of Chicago 1983-86). NATO Postdoctoral Fellowship (1987-88). The Ohio State University Alumni Award for Distinguished Teaching (1999). Fellow of the American Physical Society (2001). 5th Prize, Gravity Research Foundation Essay Competition (2007). Klopsteg Memorial Award, American Association of Physics Teachers (2010). Books Quantum Mechanics: An Accessible Introduction Robert J. -
THEO MURPHY INTERNATIONAL SCIENTIFIC MEETING on Testing
THEO MURPHY INTERNATIONAL SCIENTIFIC MEETING ON Testing general relativity with cosmology Monday 28 February – Tuesday 1 March 2011 The Kavli Royal Society International Centre, Chicheley Hall, Buckinghamshire Organised by Professor Pedro Ferreira, Professor Rachel Bean and Professor Andrew Taylor - Programme and abstracts - Speaker biographies The abstracts that follow are provided by the presenters and the Royal Society takes no responsibility for their content. Testing general relativity with cosmology Monday 28 February – Tuesday 1 March 2011 The Kavli Royal Society Centre, Chicheley Hall, Buckinghamshire Organised by Professor Pedro Ferreira, Professor Rachel Bean and Professor Andrew Taylor Day 1 – Monday 28 February 2011 09.15 Welcome by Professor Sir Peter Knight FRS , Principal, The Kavli Royal Society Centre Welcome by Professor Pedro Ferreira , Organiser 09.30 Constraining the cosmic growth history with large scale structure Professor Rachel Bean, Cornell University, USA 10.00 Discussion 10.15 One gravitational potential or two? Forecasts and tests Professor Edmund Bertschinger, Massachusetts Institute of Technology, USA 10.45 Discussion 11.00 Coffee 11.30 Cosmological tests of gravity Dr Constantinos Skordis, The University of Nottingham, UK 12.00 Discussion 12.15 Testing modified gravity with next generation weak lensing experiments Dr Thomas Kitching, University of Edinburgh, UK 12.45 Discussion 13.00 Lunch 14.00 Model independent tests of cosmic gravity Professor Eric Linder, University of California at Berkeley, USA 14.30 -
Women of Goddard: Careers in Science, Technology, Engineering, and Mathematics
Women of Goddard: Careers in Science, Technology, Engineering, and Mathematics Engineering, Technology, Careers in Science, of Goddard: Women National Aeronautics and Space Administration Goddard of Parkinson, Millar, Thaller Millar, Parkinson, Careers in Science Technology Engineering & Mathematics Women www.nasa.gov Women of Goddard NASA’s Goddard Space Flight Center IV&V, WV Goddard Institute for Space Studies, Greenbelt, Maryland, Main Campus Wallops Flight Facility, Virginia New York City Testing and Integration Facility, Greenbelt Home of Super Computing and Data Storage, Greenbelt GSFC’s new Sciences and Exploration Building, Greenbelt Women of Goddard: Careers in Science, Technology, Engineering, and Mathematics Editors: Claire L. Parkinson, Pamela S. Millar, and Michelle Thaller Graphics and Layout: Jay S. Friedlander In Association with: The Maryland Women’s Heritage Center (MWHC) NASA Goddard Space Flight Center, Greenbelt, Maryland, July 2011 Women of Goddard Careers in Foreword Science A century ago women in the United States could be schoolteachers and nurses but were largely excluded from the vast majority of other jobs that could Technology be classified as Science, Technology, Engineering, or Mathematics (STEM careers). Some inroads were fortuitously made during World Wars I and II, when because of Engineering the number of men engaged in fighting overseas it became essential that women fill in on jobs of all types on the home front. However, many of these inroads Mathematics were lost after the wars ended and the men -
Progress in Nuclear Astrophysics of East and Southeast Asia
Aziz et al. AAPPS Bulletin (2021) 31:18 AAPPS Bulletin https://doi.org/10.1007/s43673-021-00018-z Review article Open Access Progress in nuclear astrophysics of east and southeast Asia Azni Abdul Aziz1, Nor Sofiah Ahmad2,S.Ahn3,WakoAoki4, Muruthujaya Bhuyan2, Ke-Jung Chen5,Gang Guo6,7,K.I.Hahn8,9, Toshitaka Kajino4,10,11*, Hasan Abu Kassim2,D.Kim12, Shigeru Kubono13,14, Motohiko Kusakabe11,15,A.Li15, Haining Li16,Z.H.Li17,W.P.Liu17*,Z.W.Liu18, Tohru Motobayashi14, Kuo-Chuan Pan19,20,21,22, T.-S. Park12, Jian-Rong Shi16,23, Xiaodong Tang24,25* ,W.Wang26,Liangjian Wen27, Meng-Ru Wu5,6, Hong-Liang Yan16,23 and Norhasliza Yusof2 Abstract Nuclear astrophysics is an interdisciplinary research field of nuclear physics and astrophysics, seeking for the answer to a question, how to understand the evolution of the universe with the nuclear processes which we learn. We review the research activities of nuclear astrophysics in east and southeast Asia which includes astronomy, experimental and theoretical nuclear physics, and astrophysics. Several hot topics such as the Li problems, critical nuclear reactions and properties in stars, properties of dense matter, r-process nucleosynthesis, and ν-process nucleosynthesis are chosen and discussed in further details. Some future Asian facilities, together with physics perspectives, are introduced. Keywords: Nuclear astrophysics, East and southeast Asia 1 Introduction • What are the nuclear reactions that drive the Nuclear astrophysics deals with astronomical phenomena evolution of stars and stellar explosions? involving atomic nuclei, and therefore, it is an interdis- ciplinary field that consists of astronomy, astrophysics, The research involves close collaboration among and nuclear physics. -
China's First Step Towards Probing the Expanding Universe and the Nature of Gravity Using a Space Borne Gravitational Wave
PERSPECTIVE https://doi.org/10.1038/s42005-021-00529-z OPEN China’s first step towards probing the expanding universe and the nature of gravity using a space borne gravitational wave antenna The Taiji Scientific Collaboration* In this perspective, we outline that a space borne gravitational wave detector network combining LISA and Taiji can be used to measure the Hubble constant with an uncertainty less than 0.5% in ten years, compared with the network of the ground based gravitational wave detectors which can measure the Hubble constant within a 2% uncertainty in the next five years by the standard siren method. Taiji is a Chinese space borne gravitational wave 1234567890():,; detection mission planned for launch in the early 2030 s. The pilot satellite mission Taiji-1 has been launched in August 2019 to verify the feasibility of Taiji. The results of a few tech- nologies tested on Taiji-1 are presented in this paper. he observation of gravitational waves (GWs) enables us to explore the Universe in more Tdetails than that is currently known. By testing the theory of general relativity, it can unveil the nature of gravity. In particular, a GW can be used to determine the Hubble constant by a standard siren method1,2. This method3 was first used by the Advanced LIGO4 and Virgo5 observatories when they discovered GW event GW1708176. Despite the degeneracy problem in the ground-based GW detectors, the Hubble constant can reach a precision of 2% after a 5-year observation with the network of the current surface GW detectors6, although LIGO’s O3 data have shown that the chance to detect electromagnetic (EM) counterpart might be a little optimistic7. -
Arxiv:2108.11151V1 [Gr-Qc] 25 Aug 2021 Aee Siain 2,27]
Alternative LISA-TAIJI networks: detectability to isotropic stochastic gravitational wave background Gang Wang1, ∗ and Wen-Biao Han1, 2, 3, † 1Shanghai Astronomical Observatory, Chinese Academy of Sciences, Shanghai 200030, China 2Hangzhou Institute for Advanced Study, University of Chinese Academy of Sciences, Hangzhou 310124, China 3School of Astronomy and Space Science, University of Chinese Academy of Sciences, Beijing 100049, China (Dated: August 26, 2021) In previous work [1], three TAIJI orbital deployments have been proposed to compose alternative LISA-TAIJI networks, TAIJIm (leading the Earth by 20◦ and −60◦ inclined with respect to ecliptic plane), TAIJIp (leading the Earth by 20◦ and +60◦ inclined), TAIJIc (colocated and coplanar with LISA) with respect to LISA mission (trailing the Earth by 20◦ and +60◦ inclined). And the LISA-TAIJIm network has been identified as the most capable configuration for massive black hole binary observation. In this work, we examine the performance of three networks to the stochastic gravitational wave background (SGWB) especially for the comparison of two eligible configurations, LISA-TAIJIm and LISA-TAIJIp. This investigation shows that the detectability of LISA-TAIJIm is competitive with the LISA-TAIJIp network for some specific SGWB spectral shapes. And the capability of LISA-TAIJIm is also identical to LISA-TAIJIp to separate the SGWB components by determining the parameters of signals. Considering the performances on SGWB and massive black hole binaries observations, the TAIJIm could be recognized as an optimal option to fulfill joint observations with LISA. I. INTRODUCTION In previous work, we proposed three TAIJI orbits to construct LISA-TAIJI networks and investigated their More than fifty gravitational wave (GW) events have performances on sky localizations for MBH binaries, con- been detected during the Advanced LIGO and Ad- straints on polarizations, and overlap reduction functions vanced Virgo observing runs O1-O3a, and all signals [1]. -
Space Activities 2019
Space Activities in 2019 Jonathan McDowell [email protected] 2020 Jan 12 Rev 1.3 Contents Preface 3 1 Orbital Launch Attempts 3 1.1 Launch statistics by country . 3 1.2 Launch failures . 4 1.3 Commercial Launches . 4 2 Satellite Launch Statistics 6 2.1 Satellites of the major space powers, past 8 years . 6 2.2 Satellite ownership by country . 7 2.3 Satellite manufacture by country . 11 3 Scientific Space Programs 11 4 Military Space Activities 12 4.1 Military R&D . 12 4.2 Space surveillance . 12 4.3 Reconnaissance and Signals Intelligence . 13 4.4 Space Weapons . 13 5 Special Topics 13 5.1 The Indian antisatellite test and its implications . 13 5.2 Starlink . 19 5.3 Lightsail-2 . 24 5.4 Kosmos-2535/2536 . 25 5.5 Kosmos-2542/2543 . 29 5.6 Starliner . 29 5.7 OTV-5 and its illegal secret deployments . 32 5.8 TJS-3 . 33 6 Orbital Debris and Orbital Decay 35 6.1 Disposal of launch vehicle upper stages . 36 6.2 Orbituaries . 39 6.3 Retirements in the GEO belt . 42 6.4 Debris events . 43 7 Acknowledgements 43 Appendix 1: 2019 Orbital Launch Attempts 44 1 Appendix 2a: Satellite payloads launched in 2018 (Status end 2019) 46 Appendix 2b: Satellite payloads deployed in 2018 (Revised; Status end 2019) 55 Appendix 2c: Satellite payloads launched in 2019 63 Appendix 2d: Satellite payloads deployed in 2019 72 Rev 1.0 - Jan 02 Initial version Rev 1.1 - Jan 02 Fixed two incorrect values in tables 4a/4b Rev 1.2 - Jan 02 Minor typos fixed Rev 1.3 - Jan 12 Corrected RL10 variant, added K2491 debris event, more typos 2 Preface In this paper I present some statistics characterizing astronautical activity in calendar year 2019. -
Jhep05(2021)160
Published for SISSA by Springer Received: March 4, 2021 Accepted: May 3, 2021 Published: May 19, 2021 Phase transition gravitational waves from pseudo-Nambu-Goldstone dark matter and two Higgs JHEP05(2021)160 doublets Zhao Zhang, Chengfeng Cai, Xue-Min Jiang, Yi-Lei Tang,1 Zhao-Huan Yu1 and Hong-Hao Zhang1 School of Physics, Sun Yat-Sen University, Guangzhou 510275, China E-mail: [email protected], [email protected], [email protected], [email protected], [email protected], [email protected] Abstract: We investigate the potential stochastic gravitational waves from first-order electroweak phase transitions in a model with pseudo-Nambu-Goldstone dark matter and two Higgs doublets. The dark matter candidate can naturally evade direct detection bounds, and can achieve the observed relic abundance via the thermal mechanism. Three scalar fields in the model obtain vacuum expectation values, related to phase transitions at the early Universe. We search for the parameter points that can cause first-order phase transitions, taking into account the existed experimental constraints. The resulting grav- itational wave spectra are further evaluated. Some parameter points are found to induce strong gravitational wave signals, which have the opportunity to be detected in future space-based interferometer experiments LISA, Taiji, and TianQin. Keywords: Beyond Standard Model, Cosmology of Theories beyond the SM, Higgs Physics, Thermal Field Theory ArXiv ePrint: 2102.01588 1Corresponding author. Open Access, c The Authors. https://doi.org/10.1007/JHEP05(2021)160 Article funded by SCOAP3. Contents 1 Introduction1 2 The model2 3 Experimental bounds5 4 Effective potential6 JHEP05(2021)160 5 Phase transitions 10 6 Gravitational wave spectra 14 7 Numerical analyses 16 8 Summary 21 1 Introduction It is conventionally believed that dark matter (DM) originates from thermal production at the early Universe [1–3]. -
Perturbation Theories in Astrophysics: from Large-Scale Structure to Compact Objects
Perturbation Theories in Astrophysics: From Large-Scale Structure To Compact Objects Dissertation Presented in Partial Fulfillment of the Requirements for the Degree Doctor of Philosophy in the Graduate School of The Ohio State University By Xiao Fang, B.S., M.S. Graduate Program in Physics The Ohio State University 2018 Dissertation Committee: Christopher M. Hirata, Advisor Todd A. Thompson John F. Beacom Amy L. Connolly Stuart A. Raby c Copyright by Xiao Fang 2018 Abstract Although the ΛCDM model seems to be a very successful model for our observed Universe, puzzles remain puzzling. Current and future cosmology analyses aim to test the ΛCDM model, understand the nature of dark matter and dark energy, and learn about the beginning of the Universe. All of these require better modeling of cosmological probes. In this thesis, I focus on improving cosmology analyses in dif- ferent ways. On the one hand, ongoing and upcoming large-scale structure surveys provide the opportunity to measure the properties of the Universe to unprecedented precision. On the other hand, compact objects, responsible for some of the most vio- lent phenomena observable on cosmological scales, play a unique role in determining the expansion history of the Universe. I present our work on developing accurate and extremely efficient tools for analyzing the next generation cosmology datasets, and characterizing systematic uncertainties associated with using compact objects as cosmological probes. ii Acknowledgments I would like to thank all my collaborators, without whom the research contained in this thesis and in the more complete publication list would not be done. Their names have been enumerated in the publication author lists and some of them will also be mentioned later.