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Parallel Sessions
Identification of Dark Matter July 23-27, 2012 9th International Conference Chicago, IL http://kicp-workshops.uchicago.edu/IDM2012/ PARALLEL SESSIONS http://kicp.uchicago.edu/ http://www.nsf.gov/ http://www.uchicago.edu/ http://www.fnal.gov/ International Advisory Committee Daniel Akerib Elena Aprile Rita Bernabei Case Western Reserve University, Columbia University, USA Universita degli Studi di Roma, Italy Cleveland, USA Gianfranco Bertone Joakim Edsjo Katherine Freese University of Amsterdam Oskar Klein Centre / Stockholm University of Michigan, USA University Richard Gaitskell Gilles Gerbier Anne Green Brown University, USA IRFU/ CEA Saclay, France University of Nottingham, UK Karsten Jedamzik Xiangdong Ji Lawrence Krauss Universite de Montpellier, France University of Maryland, USA Arizona State University, USA Vitaly Kudryavtsev Reina Maruyama Leszek Roszkowski University of Sheffield University of Wisconsin-Madison University of Sheffield, UK Bernard Sadoulet Pierre Salati Daniel Santos University of California, Berkeley, USA University of California, Berkeley, USA LPSC/UJF/CNRS Pierre Sikivie Daniel Snowden-Ifft Neil Spooner University of Florida, USA Occidental College University of Sheffield, UK Max Tegmark Karl van Bibber Kavli Institute for Astrophysics & Space Naval Postgraduate School Monterey, Research at MIT, USA USA Local Organizing Committee Daniel Bauer Matthew Buckley Juan Collar Fermi National Accelerator Laboratory Fermi National Accelerator Laboratory Kavli Institute for Cosmological Physics Scott Dodelson Aimee -
AAS Worldwide Telescope: Seamless, Cross-Platform Data Visualization Engine for Astronomy Research, Education, and Democratizing Data
AAS WorldWide Telescope: Seamless, Cross-Platform Data Visualization Engine for Astronomy Research, Education, and Democratizing Data The Harvard community has made this article openly available. Please share how this access benefits you. Your story matters Citation Rosenfield, Philip, Jonathan Fay, Ronald K Gilchrist, Chenzhou Cui, A. David Weigel, Thomas Robitaille, Oderah Justin Otor, and Alyssa Goodman. 2018. AAS WorldWide Telescope: Seamless, Cross-Platform Data Visualization Engine for Astronomy Research, Education, and Democratizing Data. The Astrophysical Journal: Supplement Series 236, no. 1. Published Version https://iopscience-iop-org.ezp-prod1.hul.harvard.edu/ article/10.3847/1538-4365/aab776 Citable link http://nrs.harvard.edu/urn-3:HUL.InstRepos:41504669 Terms of Use This article was downloaded from Harvard University’s DASH repository, and is made available under the terms and conditions applicable to Open Access Policy Articles, as set forth at http:// nrs.harvard.edu/urn-3:HUL.InstRepos:dash.current.terms-of- use#OAP Draft version January 30, 2018 Typeset using LATEX twocolumn style in AASTeX62 AAS WorldWide Telescope: Seamless, Cross-Platform Data Visualization Engine for Astronomy Research, Education, and Democratizing Data Philip Rosenfield,1 Jonathan Fay,1 Ronald K Gilchrist,1 Chenzhou Cui,2 A. David Weigel,3 Thomas Robitaille,4 Oderah Justin Otor,1 and Alyssa Goodman5 1American Astronomical Society 1667 K St NW Suite 800 Washington, DC 20006, USA 2National Astronomical Observatories, Chinese Academy of Sciences 20A Datun Road, Chaoyang District Beijing, 100012, China 3Christenberry Planetarium, Samford University 800 Lakeshore Drive Birmingham, AL 35229, USA 4Aperio Software Ltd. Headingley Enterprise and Arts Centre, Bennett Road Leeds, LS6 3HN, United Kingdom 5Harvard Smithsonian Center for Astrophysics 60 Garden St. -
Space Astronomy in the 90S
Space Astronomy in the 90s Jonathan McDowell April 26, 1995 1 Why Space Astronomy? • SHARPER PICTURES (Spatial Resolution) The Earth’s atmosphere messes up the light coming in (stars twinkle, etc). • TECHNICOLOR (X-ray, infrared, etc) The atmosphere also absorbs light of different wavelengths (col- ors) outside the visible range. X-ray astronomy is impossible from the Earth’s surface. 2 What are the differences between satellite instruments? • Focussing optics or bare detectors • Wavelength or energy range - IR, UV, etc. Different technology used for different wavebands. • Spatial Resolution (how sharp a picture?) • Spatial Field of View (how large a piece of sky?) • Spectral Resolution (can it tell photons of different energies apart?) • Spectral Field of View (bandwidth) • Sensitivity • Pointing Accuracy • Lifetime • Orbit (hence operating efficiency, background, etc.) • Scan or Point What are the differences between satellites? • Spinning or 3-axis pointing (older satellites spun around a fixed axis, precession let them eventually see different parts of the sky) • Fixed or movable solar arrays (fixed arrays mean the spacecraft has to point near the plane perpendicular to the solar-satellite vector) 3 • Low or high orbit (low orbit has higher radiation, atmospheric drag, and more Earth occultation; high orbit has slower preces- sion and no refurbishment opportunity) • Propulsion to raise orbit? • Other consumables (proportional counter gas, attitude control gas, liquid helium coolant) 4 What are the differences in operation? • PI mission vs. GO mission PI = Principal Investigator. One of the people responsible for building the satellite. Nowadays often referred to as IPIs (In- strument PIs). GO = Guest Observer. Someone who just want to use the satel- lite. -
Development of a Liquid Xenon Time Projection Chamber for the XENON Dark Matter Search
Development of a Liquid Xenon Time Projection Chamber for the XENON Dark Matter Search Kaixuan Ni Submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy in the Graduate School of Arts and Sciences COLUMBIA UNIVERSITY 2006 c 2006 Kaixuan Ni All rights reserved Development of a Liquid Xenon Time Projection Chamber for the XENON Dark Matter Search Kaixuan Ni Advisor: Professor Elena Aprile Submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy in the Graduate School of Arts and Sciences COLUMBIA UNIVERSITY 2006 c 2006 Kaixuan Ni All rights reserved ABSTRACT Development of a Liquid Xenon Time Projection Chamber for the XENON Dark Matter Search Kaixuan Ni This thesis describes the research conducted for the XENON dark matter direct detection experiment. The tiny energy and small cross-section, from the interaction of dark matter particle on the target, requires a low threshold and sufficient background rejection capability of the detector. The XENON experiment uses dual phase technology to detect scintillation and ionization simultaneously from an event in liquid xenon (LXe). The distinct ratio, be- tween scintillation and ionization, for nuclear recoil and electron recoil events provides excellent background rejection potential. The XENON detector is designed to have 3D position sensitivity down to mm scale, which provides additional event information for background rejection. Started in 2002, the XENON project made steady progress in the R&D phase during the past few years. Those include developing sensitive photon detectors in LXe, improving the energy resolution and LXe purity for detect- ing very low energy events. -
Particle Acceleration in Solar Flares What Is the Link Between Heating and Particle Acceleration?
Energetic Particles in the Solar Atmosphere (X- ray diagnostics) Nicole Vilmer LESIA, Observatoire de Paris, CNRS, UPMC, Université Paris-Diderot The Sun as a Particle Accelerator: First detection of energetic protons from the Sun(1942) (related to a solar flare) First X-ray observations of solar flares (1970) Chupp et al., 1974 First observations of -ray lines from solar flares (OSO7/Prognoz 1972) Since then many more observations With e.g. RHESSI (2002-2018) And also INTEGRAL, FERMI >120000 X-ray flares observed by RHESSI (NASA/SMEX; 2002-2018) But still a limited number of gamma- ray line flares ~30 Solar flare: Sudden release of magnetic energy Heating Particle acceleration X-rays 6-8 keV 25-80 keV 195 Å 304 Å 21 aug 2002 (extreme ultraviolet) 335 Å 15 fev 2011 HXR/GR diagnostics of energetic electrons and ions SXR emission Hot Plasma (7to 8 MK ) HXR emission Bremsstrahlung from non-thermal electrons Prompt -ray lines : Deexcitation lines(C and 0) (60%) Signature of energetic ions (>2 MeV/nuc) Neutron capture line: p –p ; p-α and p-ions interactions Production of neutrons Collisional slowing down of neutrons Radiative capture on ambient H deuterium + 2.2 MeV. line RHESSI Observations X/ spectrum Thermal components T= 2 10 7 K T= 4 10 7 K Electron bremsstrahlung Ultrarelativistic -ray lines Electron (ions > 3 MeV/nuc) Bremsstrahlung (INTEGRAL) SMM/GRS PHEBUS/GRANAT FERMI/LAT observations RHESSI Pion decay radiation(ions > ~300MeV/nuc) Particle acceleration in solar flares What is the link between heating and particle acceleration? Where are the acceleration sites? What is the transport of particles from acceleration sites to X/ γ ray emission sites? What are the characteristic acceleration times? RHESSI How many energetic particles? Energy spectra? Relative abundances of energetic ions? RHESSI Which acceleration mechanisms in solar flares? Shock acceleration? Stochastic acceleration? (wave-particle interaction) Direct Electric field acceleration. -
Centaurus a at Hard X-Rays and Gamma Rays
Centaurus A at Hard X-Rays and Soft Gamma-Rays Chandra 1-10 keV CGRO-COMPTEL 1 ± 30 MeV Fermi 100 MeV ± 100 GeV Helmut Steinle Max-Planck-Institut für extraterrestrische Physik Garching, Germany ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- The Many Faces of Centaurus A ± Sydney, 28 June ± 3 July 2009; H. Steinle, MPE 1 / 35 Centaurus A at Hard X-Rays and Soft Gamma-Rays Contents · Introduction · The Spectral Energy Distribution · Properties of the existing measurements in the hard X-ray / soft Gamma-ray regime · Important satellites for this energy / frequency range · Variability of the X-ray / Gamma-ray emission · Two examples of models for the Cen A Spectral Energy Distribution · Problems (features) to be considered when using the hard X-ray / soft Gamma-ray data ± the ªsoft X-ray transient problemº ± the ªSED problemº · Outlook ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- The Many Faces of Centaurus A ± Sydney, 28 June ± 3 July 2009; H. Steinle, MPE 2 / 35 Centaurus A at Hard X-Rays and Soft Gamma-Rays ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- Introduction In the introductory (ªsetting the stageº) section of the -
Dark Matter Working Group Executive Summary (Ness '02)
Dark Matter Working Group Executive Summary (NeSS ’02) Working Group Leaders: Rick Gaitskell, Brown; and Dick Arnowitt, Texas A&M. (Document Version 020925v21) Working Group Members: Craig Aalseth, PNL; Dan Akerib, CWRU; Elena Aprile, Columbia; Priscilla Cushman, U. Minnesota; John Ellis, CERN; Jonathan Feng, UC Irvine; Gilles Gerbier, Saclay; Alexander Kusenko, UCLA; Kirk McDonald, Princeton; Jeff Martoff, Temple; Richard Schnee, CWRU; and Nigel Smith, RAL. Introduction No currently observed particle is a suitable candidate for cold dark matter. The solution to the non baryonic dark matter problem, both in the universe as a whole, and in our own galaxy, may be resolved by physics found at the intersection of astronomy, high energy particle physics, and cosmology. The main candidates for this dark matter are relic particles generated, in great abundance, shortly after the Big Bang. Currently, there are 20 operating experiments designed to perform the direct detection of these particles being conducted at all the underground physics laboratories worldwide (bar one). One of them is sited at a US underground laboratory, although US sourced funding is made to six experiments. Existing results have put significant constraints on the allowed particle theories of dark matter, with one experiment claiming a positive observation, yet to be confirmed by other experiments. The planned dark matter experiments that were discussed at this workshop would be able to cover most of the parameter space of major theoretical proposals. The new physics required for particle dark matter is also expected to be discovered in the next round of high energy accelerator experiments (LHC, NLC). Theoretically and experimentally there is great complementarity between direct detection and accelerator programs. -
Testing the Purity Monitor for the XENON Dark Matter Search
Testing the Purity Monitor for the XENON Dark Matter Search Alison Andrews Laboratori Nazionali del Gran Sasso Columbia University REU August 4, 2006 1 Introduction Evidence for dark matter is found in many observed features of the universe. New- q GM(r) tonian gravitation predicts the rotational velocities of galaxies by v(r) = r , where mass is described by M(r) = 4π R ρ(r)r2dr. Actual measurements of the rota- tional velocities of galaxies, however, describe a distribution of mass where M(r) ∝ r. Fritz Zwicky studied this inconsistency in the Coma galaxy cluster in 1933, and he proposed the existence of a non-luminous dark matter. Over thirty years later, Vera Rubin supported Zwickys work with additional observations of galaxy rotational 1 curves. Their studies imply the existence of a halo of dark matter with ρ(r) ∝ r2 . Further evidence of dark matter is gravitational lensing. The General Theory of Relativity predicts the bending of light through areas of gravitational potential. Observations of this phenomenon show that the amount of bending around galaxy clusters corresponds to a greater amount of mass than is visible. Dark matter also helps to explain the formation and temperature distribution of the universe. A favored candidate for cold non-baryonic dark matter is the Weakly Interac- tive Massive Particle (or WIMP). Direct detection of WIMPs in experiments like XENON aim to detect the energy released from the elastic scattering of a WIMP off a terrestrial nucleus. 1 2 The XENON Dark Matter Search The XENON experiment aims to detect dark matter particles by measuring the scintillation and ionization of the nuclear recoils which result from the elastic collision of WIMPs with Xe nuclei using a dual phase (liquid/gas) xenon time projection chamber. -
Elena Aprile Columbia University
XENON1T: First Results (arXiv:1705.06655) Elena Aprile Columbia University Patras Axion-Wimp 2017 May 15-19 Thessaloniki, Greece 1 XENON World ~130 scientists from 22 institutions Laboratori Nazionali del Gran Sasso (LNGS), Italy XENON1T Elena Aprile (Columbia) XENON1T: First Results @ Patras Axion-WIMP 2017 2 Phases of the XENON program XENON10 XENON100 XENON1T / XENONnT 2005-2007 2008-2016 2013-2018 / 2019-2023 15 cm drift TPC – 25 kg 30 cm drift TPC – 161 kg 100 cm / 144 cm drift TPC - 3200 kg / ~8000 kg Achieved (2007) Achieved (2016) Projected (2018) / Projected (2023) σ -44 2 σ -45 2 σ -47 2 σ -48 2 SI = 8.8 x 10 cm SI = 1.1 x 10 cm SI = 1.6 x 10 cm / SI = 1.6 x 10 cm Elena Aprile (Columbia) XENON1T: First Results @ Patras Axion-WIMP 2017 3 The XENON1T Experiment Elena Aprile (Columbia) XENON1T: First Results @ Patras Axion-WIMP 2017 4 The XENON1T Experiment Elena Aprile (Columbia) XENON1T: First Results @ Patras Axion-WIMP 2017 4 July 2013 Uwe Oberlack LNGS SC Meeting - 29-Oct-2013 17 Aug. 2014 XENON1T Cryostat 7 XENON1T Cryostat 7 XENON1T Cryostat 7 XENON1T Cryostat 7 XENON1T Cryostat 7 Time Projection Chamber Eur. Phys. J. C 75, no. 11, 546 (2015) Elena Aprile (Columbia) XENON1T: First Results @ Patras Axion-WIMP 2017 8 Cryostat in the Water Tank Elena Aprile (Columbia) XENON1T: First Results @ Patras Axion-WIMP 2017 9 Cherenkov Muon Veto • Active shield against muons • 84 high-QE 8'' Hamamatsu R5912 PMTs • Trigger efficiency > 99.5% for neutrons with muons in water tank • Can suppress cosmogenic background to < 0.01 events/ton/year -
Astronomy and Astrophysics
THE DECADE OF DISCOVERY IN ASTRONOMY AND ASTROPHYSICS Astronomy and Astrophysics Survey Committee Board on Physics and Astronomy Commission on Physical Sciences, Mathematics, and Applications National Research Council NATIONAL ACADEMY PRESS Washington, D.C. 1991 NATIONAL ACADEMY PRESS • 2101 Constitution Avenue, NW • Washington, DC 20418 NOTICE: The project that is the subject of this report was approved by the Governing Board of the National Research Council, whose members are drawn from the councils of the National Academy of Sciences, the National Academy of Engineering, and the Institute of Medicine. The members of the committee responsible for the report were chosen for their special compe_nces and with regard for appropriate balance. This report has been reviewed by a group other than the authors according to procedures approved by a Report Review Committee consisting of members of the National Academy of Sciences, the National Academy of Engineering, and the Institute of Medicine. This project was supported by the Department of Energy under Grant No. DE-FGO5- 89ER40421, the National Aeronautics and Space Administration and the National Science Foundation under Grant No. AST-8901685, the Naval Research Laboratory under Contract No. N00173-90-M-9744, and the Smithsonian Institution under Purchase Order No. SF0022430000. Additional support was provided by the Maurice Ewing Earth and Planetary Sciences Fund of the National Academy of Sciences created through a gift from the Palisades Geophysical Institute, Inc., and an anonymous donor. Library of Congress Cataloging-in-Publication Data National Research Council (U.S.). Astronomy and Astrophysics Survey Committee. The decade of discovery in astronomy and astrophysics / Astronomy and Astrophysics Survey Committee, Board on Physics and Astronomy, Commission on Physical Sciences, Mathematics, and Applications, National Research Council. -
Experiments on the Differential Vlbi Measurements with the Former Russian Deep Space Network
EXPERIMENTS ON THE DIFFERENTIAL VLBI MEASUREMENTS WITH THE FORMER RUSSIAN DEEP SPACE NETWORK Igor E. Molotov(1,2,3) (1)Bear Lakes Radio Astronomy Station of Central (Pulkovo) Astronomical Observatory, Pulkovskoye chosse 65/1, Saint-Petersburg, 196140, Russia , E-mail: [email protected] (2)Keldysh Institute of Applied Mathematics, Miusskaja sq. 4, 125047 Moscow, Russia (3)Central Research Institute for Machine Building, 4 Pionerskaya Street, Korolev, 141070, Russia ABSTRACT The differential VLBI technique (delta-VLBI) is applied transforms the signals into video frequencies, which for measuring spacecraft position with accuracy up to 1 then are sampled with 1- or 2-bit quantization, formatted in any standard VLBI format (Mk-4, S2, K-4, mas. This procedure allows to link the sky position of object with the position of close ICRF quasar on the Mk-2) and recorded on magnetic tapes or PC-disks celestial sphere. Few delta-VLBI measurements can together with precise clock using VLBI terminal. All frequency transformations are connected with atomic urgently improve the knowledge of object trajectory in the times of critical maneuvers. frequency standard. The tapes/disks from all radio telescopes of VLBI array are collected at data The Russian Deep Space Network that was based on processing center, where the data are cross-correlated. three large antennas: 70 m in Evpatoria (Ukraine) and The processing is aimed to measure the time delay of Ussuriysk (Far East), and 64 m in Bear Lakes (near emitted wavefront arrival to receiving antennas, and Moscow) arranged the trial delta-VLBI experiments frequency of interference (fringe rate), that contain the with help of four scientific institutions. -
GRANAT/WATCH Catalogue of Cosmic Gamma-Ray Bursts: December 1989 to September 1994? S.Y
ASTRONOMY & ASTROPHYSICS APRIL I 1998,PAGE1 SUPPLEMENT SERIES Astron. Astrophys. Suppl. Ser. 129, 1-8 (1998) GRANAT/WATCH catalogue of cosmic gamma-ray bursts: December 1989 to September 1994? S.Y. Sazonov1,2, R.A. Sunyaev1,2, O.V. Terekhov1,N.Lund3, S. Brandt4, and A.J. Castro-Tirado5 1 Space Research Institute, Russian Academy of Sciences, Profsoyuznaya 84/32, 117810 Moscow, Russia 2 Max-Planck-Institut f¨ur Astrophysik, Karl-Schwarzschildstr 1, 85740 Garching, Germany 3 Danish Space Research Institute, Juliane Maries Vej 30, DK 2100 Copenhagen Ø, Denmark 4 Los Alamos National Laboratory, MS D436, Los Alamos, NM 87545, U.S.A. 5 Laboratorio de astrof´ısica Espacial y F´ısica Fundamental (LAEFF), INTA, P.O. Box 50727, 28080 Madrid, Spain Received May 23; accepted August 8, 1997 Abstract. We present the catalogue of gamma-ray bursts celestial positions (the radius of the localization region is (GRB) observed with the WATCH all-sky monitor on generally smaller than 1 deg at the 3σ confidence level) board the GRANAT satellite during the period December of short-lived hard X-ray sources, which include GRBs. 1989 to September 1994. The cosmic origin of 95 bursts Another feature of the instrument relevant to observa- comprising the catalogue is confirmed either by their lo- tions of GRBs is that its detectors are sensitive over an calization with WATCH or by their detection with other X-ray energy range that reaches down to ∼ 8 keV, the do- GRB experiments. For each burst its time history and main where the properties of GRBs are known less than information on its intensity in the two energy ranges at higher energies.