An Illuminating Blast from the Universe's Past
Total Page:16
File Type:pdf, Size:1020Kb

Load more
Recommended publications
-
Precollimator for X-Ray Telescope (Stray-Light Baffle) Mindrum Precision, Inc Kurt Ponsor Mirror Tech/SBIR Workshop Wednesday, Nov 2017
Mindrum.com Precollimator for X-Ray Telescope (stray-light baffle) Mindrum Precision, Inc Kurt Ponsor Mirror Tech/SBIR Workshop Wednesday, Nov 2017 1 Overview Mindrum.com Precollimator •Past •Present •Future 2 Past Mindrum.com • Space X-Ray Telescopes (XRT) • Basic Structure • Effectiveness • Past Construction 3 Space X-Ray Telescopes Mindrum.com • XMM-Newton 1999 • Chandra 1999 • HETE-2 2000-07 • INTEGRAL 2002 4 ESA/NASA Space X-Ray Telescopes Mindrum.com • Swift 2004 • Suzaku 2005-2015 • AGILE 2007 • NuSTAR 2012 5 NASA/JPL/ASI/JAXA Space X-Ray Telescopes Mindrum.com • Astrosat 2015 • Hitomi (ASTRO-H) 2016-2016 • NICER (ISS) 2017 • HXMT/Insight 慧眼 2017 6 NASA/JPL/CNSA Space X-Ray Telescopes Mindrum.com NASA/JPL-Caltech Harrison, F.A. et al. (2013; ApJ, 770, 103) 7 doi:10.1088/0004-637X/770/2/103 Basic Structure XRT Mindrum.com Grazing Incidence 8 NASA/JPL-Caltech Basic Structure: NuSTAR Mirrors Mindrum.com 9 NASA/JPL-Caltech Basic Structure XRT Mindrum.com • XMM Newton XRT 10 ESA Basic Structure XRT Mindrum.com • XMM-Newton mirrors D. de Chambure, XMM Project (ESTEC)/ESA 11 Basic Structure XRT Mindrum.com • Thermal Precollimator on ROSAT 12 http://www.xray.mpe.mpg.de/ Basic Structure XRT Mindrum.com • AGILE Precollimator 13 http://agile.asdc.asi.it Basic Structure Mindrum.com • Spektr-RG 2018 14 MPE Basic Structure: Stray X-Rays Mindrum.com 15 NASA/JPL-Caltech Basic Structure: Grazing Mindrum.com 16 NASA X-Ray Effectiveness: Straylight Mindrum.com • Correct Reflection • Secondary Only • Backside Reflection • Primary Only 17 X-Ray Effectiveness Mindrum.com • The Crab Nebula by: ROSAT (1990) Chandra 18 S. -
THE GAMMA RAY EXPERIMENT for the SMALL ASTRONOMY SATELLITE B (SAS-B) C. E. Fichtel, C. H..~Hrmann, R. C. Hartman, D. A. Kniffen
THE GAMMA RAY EXPERIMENT FOR THE SMALL ASTRONOMY SATELLITE B (SAS-B) C. E. Fichtel, C. H.. ~hrmann, R. C. Hartman, D. A. Kniffen, H. B. Ogelman*, and R. W. Ross Goddard Space Flight Center, Greenbelt, Md. 20771 Abstract A magnetic core digitized spark chamber gamma ray telescope has been developed for satellite use and will be flown on SAS-B in less than one year. The SAS-B detector will have the following characteristics: Effective area ~ 500 cm2 , solid angle = ~ SR; Efficiency (high energy) ~ 0.29; and time resolution of better than two milliseconds. A detailed picture of the galactic plane in gamma rays should be obtained with this experiment, and a study of point sources, including short bursts of gamma rays from supernovae explosions, will also be possible. 1. Introduction The SAS-B gamma ray telescope represents the first satellite version of a planned evolution of a gamma ray digitized spark chamber telescope which began with the development of a balloon borne instrument. The telescope is aimed at the study of gamma rays whose energy exceeds about 20 MeV. In the early 1960's, it was realized that the celestial gamma ray intensity was very low compared to the high background of cosmic ray particles and earth albedo. For this reason, a picture type detector seemed to be needed to identify unambiguously the electron pair produced by the gamma ray and to study its properties - particularly to obtain a measure of the energy and arrival direction of the gamma ray. In addition, the secondary gamma ray flux produced by cosmic rays in the atmosphere, even at the altitudes of the present large balloons, severely limits the gamma ray astronomy which can be accomplished with balloons and dictates that gamma ray ~stronomy must ultimately be accomplished with detector systems on satellites. -
Astronomical Distances
The Act of Measurement I: Astronomical Distances B. F. Riley The act of measurement causes astronomical distances to adopt discrete values. When measured, the distance to the object corresponds through an inverse 5/2 power law – the Quantum/Classical connection – to a sub-Planckian mass scale on a level or sub-level of one or both of two geometric sequences, of common ratio 1/π and 1/e, that descend from the Planck mass and may derive from the geometry of a higher-dimensional spacetime. The distances themselves lie on the levels and sub-levels of two sequences, of common ratio π and e, that ascend from the Planck length. Analyses have been performed of stellar distances, the semi-major axes of the planets and planetary satellites of the Solar System and the distances measured to quasars, galaxies and gamma-ray bursts. 1 Introduction Using Planck units the Quantum/Classical connection, characterised by the equation (1) maps astronomical distances R – in previous papers only the radii of astronomical bodies [1, 2] – onto sub-Planckian mass scales m on the mass levels and sub-levels1 of two geometric sequences that descend from the Planck mass: Sequence 1 of common ratio 1/π and Sequence 3 of common ratio 1/e.2 The sequences may derive from the geometry of a higher-dimensional spacetime [3]. First, we show that several distances associated with the Alpha Centauri system correspond through (1) to the mass scales of principal levels3 in Sequences 1 and 3. We then show that the mass scales corresponding through (1) to the distances from both Alpha Centauri and the Sun to the other stars lie on the levels and sub-levels of Sequences 1 and 3. -
HET Publication Report HET Board Meeting 3/4 December 2020 Zoom Land
HET Publication Report HET Board Meeting 3/4 December 2020 Zoom Land 1 Executive Summary • There are now 420 peer-reviewed HET publications – Fifteen papers published in 2019 – As of 27 November, nineteen published papers in 2020 • HET papers have 29363 citations – Average of 70, median of 39 citations per paper – H-number of 90 – 81 papers have ≥ 100 citations; 175 have ≥ 50 cites • Wide angle surveys account for 26% of papers and 35% of citations. • Synoptic (e.g., planet searches) and Target of Opportunity (e.g., supernovae and γ-ray bursts) programs have produced 47% of the papers and 47% of the citations, respectively. • Listing of the HET papers (with ADS links) is given at http://personal.psu.edu/dps7/hetpapers.html 2 HET Program Classification Code TypeofProgram Examples 1 ToO Supernovae,Gamma-rayBursts 2 Synoptic Exoplanets,EclipsingBinaries 3 OneorTwoObjects HaloofNGC821 4 Narrow-angle HDF,VirgoCluster 5 Wide-angle BlazarSurvey 6 HETTechnical HETQueue 7 HETDEXTheory DarkEnergywithBAO 8 Other HETOptics Programs also broken down into “Dark Time”, “Light Time”, and “Other”. 3 Peer-reviewed Publications • There are now 420 journal papers that either use HET data or (nine cases) use the HET as the motivation for the paper (e.g., technical papers, theoretical studies). • Except for 2005, approximately 22 HET papers were published each year since 2002 through the shutdown. A record 44 papers were published in 2012. • In 2020 a total of fifteen HET papers appeared; nineteen have been published to date in 2020. • Each HET partner has published at least 14 papers using HET data. • Nineteen papers have been published from NOAO time. -
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. -
SPACETIME SINGULARITIES: the STORY of BLACK HOLES
1 SPACETIME SINGULARITIES: The STORY of BLACK HOLES We have already seen that the Big Bang is a kind of 'singularity' in the structure of spacetime. To the question "what was before the Big Bang?", one can reply, at least in the context of GR, that the question actually has no meaning - that time has no meaning 'before' the Big Bang. The point is that the universe can be ¯nite in extent in both time and space, and yet have no boundary in either. We saw what a curved space which is ¯nite in size but has no boundary means for a 2-d surface - a balloon is an example. Notice that if we made a balloon that curved smoothly except at one point (we could, for example, pinch it at this point) we could say that the balloon surface curvature was singular (ie., in¯nite) at this point. The idea of a 4-d spacetime with no boundary in spacetime, but with a ¯nite spacetime 4-dimensional volume, is a simple generalization of this. And just as it makes no sense, inside a 2-d balloon, to ask where the boundary is, we can have spacetime geometries which have no boundary in space or time, or where spacetime 'terminates' at a singularity. All of this is easy to say, but the attitude of most early workers in GR was to ignore the possible existence of singularities, and/or hope that they would just go away. The reaction of Einstein to the discovery of singular solutions to his equations was quite striking. -
Arxiv:2007.07969V3 [Astro-Ph.CO] 22 Mar 2021
INR-TH-2020-032 Towards Testing Sterile Neutrino Dark Matter with Spectrum-Roentgen-Gamma Mission V. V. Barinov,1, 2, ∗ R. A. Burenin,3, 4, y D. S. Gorbunov,2, 5, z and R. A. Krivonos3, x 1Physics Department, M. V. Lomonosov Moscow State University, Leninskie Gory, Moscow 119991, Russia 2Institute for Nuclear Research of the Russian Academy of Sciences, Moscow 117312, Russia 3Space Research Institute of the Russian Academy of Sciences, Moscow 117997, Russia 4National Research University Higher School of Economics, Moscow 101000, Russia 5Moscow Institute of Physics and Technology, Dolgoprudny 141700, Russia We investigate the prospects of the SRG mission in searches for the keV-scale mass sterile neutrino dark matter radiatively decaying into active neutrino and photon. The ongoing all-sky X-ray survey of the SRG space observatory with data acquired by the ART-XC and eROSITA telescopes can provide a possibility to fully explore the resonant production mechanism of the dark matter sterile neutrino, which exploits the lepton asymmetry in the primordial plasma consistent with cosmological limits from the Big Bang Nucleosynthesis. In particular, it is shown that at the end of the four year all-sky survey, the sensitivity of the eROSITA telescope near the 3.5 keV line signal reported earlier can be comparable to that of the XMM -Newton with all collected data, which will allow one to carry out another independent study of the possible sterile neutrino decay signal in this area. In the energy range below ≈ 2:4 keV, the expected constraints on the model parameters can be significantly stronger than those obtained with XMM -Newton. -
Scientific Problems Addressed by the Spektr-UV Space Project (World Space Observatory—Ultraviolet)
ISSN 1063-7729, Astronomy Reports, 2016, Vol. 60, No. 1, pp. 1–42. c Pleiades Publishing, Ltd., 2016. Original Russian Text c A.A. Boyarchuk, B.M. Shustov, I.S. Savanov, M.E. Sachkov, D.V. Bisikalo, L.I. Mashonkina, D.Z. Wiebe, V.I. Shematovich, Yu.A. Shchekinov, T.A. Ryabchikova, N.N. Chugai, P.B. Ivanov, N.V. Voshchinnikov, A.I. Gomez de Castro, S.A. Lamzin, N. Piskunov, T. Ayres, K.G. Strassmeier, S. Jeffrey, S.K. Zwintz, D. Shulyak, J.-C. G´erard, B. Hubert, L. Fossati, H. Lammer, K. Werner, A.G. Zhilkin, P.V. Kaigorodov, S.G. Sichevskii, S. Ustamuich, E.N. Kanev, E.Yu. Kil’pio, 2016, published in Astronomicheskii Zhurnal, 2016, Vol. 93, No. 1, pp. 3–48. Scientific Problems Addressed by the Spektr-UV Space Project (World Space Observatory—Ultraviolet) A. A. Boyarchuk1, B.M.Shustov1*, I. S. Savanov1, M.E.Sachkov1, D. V. Bisikalo1, L. I. Mashonkina1, D.Z.Wiebe1,V.I.Shematovich1,Yu.A.Shchekinov2, T. A. Ryabchikova1, N.N.Chugai1, P.B.Ivanov3, N.V.Voshchinnikov4, A. I. Gomez de Castro5,S.A.Lamzin6,N.Piskunov7,T.Ayres8, K. G. Strassmeier9, S. Jeffrey10,S.K.Zwintz11, D. Shulyak12,J.-C.Gerard´ 13,B.Hubert13, L. Fossati14, H. Lammer14,K.Werner15,A.G.Zhilkin1,P.V.Kaigorodov1, S. G. Sichevskii1,S.Ustamuich5,E.N.Kanev1, and E. Yu. Kil’pio1 1Institute of Astronomy, Russian Academy of Sciences, ul. Pyatnitskaya 48, Moscow, 119017 Russia 2Southern Federal University, Rostov-on-Don, 344006 Russia 3Astro Space Center, Lebedev Physical Institute, Russian Academy of Sciences, Moscow, Russia 4St. -
NASA's Great Observatories
NASA’s Great Observatories To grasp the wonders of the cosmos, and understand its infinite variety and splendor, we must collect and analyze radiation emitted by phenomena throughout the entire electromagnetic (EM) spectrum. Towards that end, NASA proposed the concept of Great Observatories, a series of four space-borne observatories designed to conduct astronomical studies over many different wavelengths (visible, gamma rays, X-rays, and infrared). An important aspect of the Great Observatory program was to overlap the operations phases of the missions to enable astronomers to make contemporaneous observations of an object at different spectral wavelengths. The first element of the program -- and arguably the best known -- is the Hubble Space Telescope (HST). The Hubble telescope was deployed by a NASA Space Shuttle in 1990. A subsequent Shuttle mission in 1993 serviced HST and recovered its full capability. A second successful servicing mission took place in 1997. Subsequent servicing missions have added additional capabilities to HST, which observes the Universe at ultraviolet, visual, and near-infrared wavelengths. Diagram of the Space Telescope, 1981 Since its preliminary inception, HST was designed to be a different type of mission for NASA -- a long term space- based observatory. From its position 380 miles above Earth's surface, the Hubble Space Telescope has contributed enormously to astronomy. It has expanded our understanding of star birth, star death, and galaxy evolution, and has helped move black holes from scientific theory to fact. Credited with thousands of images and the subject of thousands of research papers, the space telescope is helping astronomers answer a wide range of intriguing questions about the origin and evolution of the universe. -
GRANAT/SIGMA Observation of the Early Afterglow from GRB 920723
A&A manuscript no. (will be inserted by hand later) ASTRONOMY Your thesaurus codes are: AND 13(13.07.1) ASTROPHYSICS GRANAT/SIGMA Observation of the Early Afterglow from GRB 920723 in Soft Gamma-Rays R. A. Burenin1,2, A. A. Vikhlinin1, M. R. Gilfanov1,3, O. V. Terekhov1,2, A. Yu. Tkachenko1,2, S. Yu. Sazonov1,2, E. M. Churazov1,3, R. A. Sunyaev1,3, P. Goldoni4, A. Claret4, A. Goldwurm4, J. Paul4 J. P. Roques5, E. Jourdain5, F. Pelaez6, G. Vedrenne5 1 Space Research Institute, Russian Academy of Sciences, Profsoyuznaya 84/32, 117810 Moscow, Russia 2 visiting Max-Planck-Institut für Astrophysik 3 Max-Planck-Institut für Astrophysik, Karl-Schwarzschild-Str. 1, 85740 Garching bei Munchen, Germany 4 CEA/DSM/DAPNIA/SAp, Centre d’Etudes de Saclay, 91191, Gif-sur-Yvette, Cedex, France 5 Centre d’Etude Spatiale des Rayonnements (CNRS/UPS) 9, avenue du Colonel Roche, BP 4346 31028 Toulouse Cedex, France 6 Department of Physics and Astronomy, Mississippi State University, MS 39762 the date of receipt and acceptance should be inserted later Abstract. We present a GRANAT/SIGMA observation of the fortunately, it has been impossible to observe the afterglows soft gamma-ray afterglow immediately after GRB 920723. The in the radio, optical, or X-rays earlier than approximately 10 main burst is very bright. After ∼ 6s, the burst light curve hours after the burst. makes a smooth transition into an afterglow where flux decays Some earlier observations indicated that the afterglows − as t 0.7. The power-law decay lasts for at least 1000s; beyond could immediately follow some GRB. -
Great Observatories: Paper Model
Educational Product National Aeronautics and Educators Grades 5–12 Space Administration & Students EP-1998-12-384-HQ NASA’sNASA’s GreatGreat ObservatoriesObservatories Hubble Space Chandra X-ray Compton Gamma Ray Telescope Observatory Observatory PAPER MODEL NASA’s Great Observatories: Paper Model is available in electronic format through NASA Spacelink—one of the Agency’s electronic resources specifically devel- oped for use by the educational community. The system may be accessed at the following address: http://spacelink.nasa.gov/products NASA’sNASA’s GreatGreat ObservatoriesObservatories Hubble Space Chandra X-ray Compton Gamma Ray Telescope Observatory Observatory PAPER MODEL National Aeronautics and Space Administration This publication is in the Public Domain and is not protected by copyright. Permission is not requested for duplication. EP-1998-12-384-HQ NASA’s Great Observatories Why are space observatories important? The answer concerns twinkling stars in the night sky. To reach telescopes on Earth, light from distant objects has to penetrate Earth’s atmosphere. Although the sky may look clear, the gases that make up our atmosphere cause problems for astronomers. These gases absorb the majority of radiation emanating from celestial bodies so that it never reaches the astronomer’s telescope. Radiation that does make it to the surface is distorted by pockets of warm and cool air, causing the twinkling effect. In spite of advanced computer enhancement, the images finally seen by astronomers are incomplete. Observatories located in space collect data free from the distor- tion of Earth’s atmosphere. Space observatories contain advanced, highly sensitive instruments, such as telescopes (the Hubble Space Telescope and the Chandra X-ray Observatory) and detectors (the Compton Gamma Ray Observatory and Chandra X-ray Observatory), that allow scientists to study radia- tion from neighboring planets and galaxies billions of light years away. -
Determining the Bulk Parameters of Plasma Electrons from Pitch-Angle Distribution Measurements
entropy Article Determining the Bulk Parameters of Plasma Electrons from Pitch-Angle Distribution Measurements Georgios Nicolaou 1,* , Robert Wicks 1, George Livadiotis 2, Daniel Verscharen 1,3, Christopher Owen 1 and Dhiren Kataria 1 1 Department of Space and Climate Physics, Mullard Space Science Laboratory, University College London, Dorking, Surrey RH5 6NT, UK; [email protected] (R.W.); [email protected] (D.V.); [email protected] (C.O.); [email protected] (D.K.) 2 Southwest Research Institute, San Antonio, TX 78238, USA; [email protected] 3 Space Science Center, University of New Hampshire, Durham, NH 03824, USA * Correspondence: [email protected] Received: 30 December 2019; Accepted: 11 January 2020; Published: 16 January 2020 Abstract: Electrostatic analysers measure the flux of plasma particles in velocity space and determine their velocity distribution function. There are occasions when science objectives require high time-resolution measurements, and the instrument operates in short measurement cycles, sampling only a portion of the velocity distribution function. One such high-resolution measurement strategy consists of sampling the two-dimensional pitch-angle distributions of the plasma particles, which describes the velocities of the particles with respect to the local magnetic field direction. Here, we investigate the accuracy of plasma bulk parameters from such high-resolution measurements. We simulate electron observations from the Solar Wind Analyser’s (SWA) Electron Analyser System (EAS) on board Solar Orbiter. We show that fitting analysis of the synthetic datasets determines the plasma temperature and kappa index of the distribution within 10% of their actual values, even at large heliocentric distances where the expected solar wind flux is very low.