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Pushing the Limits of the Coronagraphic Occulters on Hubble Space Telescope/Space Telescope Imaging Spectrograph
Pushing the limits of the coronagraphic occulters on Hubble Space Telescope/Space Telescope Imaging Spectrograph John H. Debes Bin Ren Glenn Schneider John H. Debes, Bin Ren, Glenn Schneider, “Pushing the limits of the coronagraphic occulters on Hubble Space Telescope/Space Telescope Imaging Spectrograph,” J. Astron. Telesc. Instrum. Syst. 5(3), 035003 (2019), doi: 10.1117/1.JATIS.5.3.035003. Downloaded From: https://www.spiedigitallibrary.org/journals/Journal-of-Astronomical-Telescopes,-Instruments,-and-Systems on 02 Jul 2019 Terms of Use: https://www.spiedigitallibrary.org/terms-of-use Journal of Astronomical Telescopes, Instruments, and Systems 5(3), 035003 (Jul–Sep 2019) Pushing the limits of the coronagraphic occulters on Hubble Space Telescope/Space Telescope Imaging Spectrograph John H. Debes,a,* Bin Ren,b,c and Glenn Schneiderd aSpace Telescope Science Institute, AURA for ESA, Baltimore, Maryland, United States bJohns Hopkins University, Department of Physics and Astronomy, Baltimore, Maryland, United States cJohns Hopkins University, Department of Applied Mathematics and Statistics, Baltimore, Maryland, United States dUniversity of Arizona, Steward Observatory and the Department of Astronomy, Tucson Arizona, United States Abstract. The Hubble Space Telescope (HST)/Space Telescope Imaging Spectrograph (STIS) contains the only currently operating coronagraph in space that is not trained on the Sun. In an era of extreme-adaptive- optics-fed coronagraphs, and with the possibility of future space-based coronagraphs, we re-evaluate the con- trast performance of the STIS CCD camera. The 50CORON aperture consists of a series of occulting wedges and bars, including the recently commissioned BAR5 occulter. We discuss the latest procedures in obtaining high-contrast imaging of circumstellar disks and faint point sources with STIS. -
Detection of Large-Scale X-Ray Bubbles in the Milky Way Halo
Detection of large-scale X-ray bubbles in the Milky Way halo P. Predehl1†, R. A. Sunyaev2,3†, W. Becker1,4, H. Brunner1, R. Burenin2, A. Bykov5, A. Cherepashchuk6, N. Chugai7, E. Churazov2,3†, V. Doroshenko8, N. Eismont2, M. Freyberg1, M. Gilfanov2,3†, F. Haberl1, I. Khabibullin2,3, R. Krivonos2, C. Maitra1, P. Medvedev2, A. Merloni1†, K. Nandra1†, V. Nazarov2, M. Pavlinsky2, G. Ponti1,9, J. S. Sanders1, M. Sasaki10, S. Sazonov2, A. W. Strong1 & J. Wilms10 1Max-Planck-Institut für Extraterrestrische Physik, Garching, Germany. 2Space Research Institute of the Russian Academy of Sciences, Moscow, Russia. 3Max-Planck-Institut für Astrophysik, Garching, Germany. 4Max-Planck-Institut für Radioastronomie, Bonn, Germany. 5Ioffe Institute, St Petersburg, Russia. 6M. V. Lomonosov Moscow State University, P. K. Sternberg Astronomical Institute, Moscow, Russia. 7Institute of Astronomy, Russian Academy of Sciences, Moscow, Russia. 8Institut für Astronomie und Astrophysik, Tübingen, Germany. 9INAF-Osservatorio Astronomico di Brera, Merate, Italy. 10Dr. Karl-Remeis-Sternwarte Bamberg and ECAP, Universität Erlangen-Nürnberg, Bamberg, Germany. †e-mail: [email protected]; [email protected]; [email protected]; [email protected]; [email protected]; [email protected] The halo of the Milky Way provides a laboratory to study the properties of the shocked hot gas that is predicted by models of galaxy formation. There is observational evidence of energy injection into the halo from past activity in the nucleus of the Milky Way1–4; however, the origin of this energy (star formation or supermassive-black-hole activity) is uncertain, and the causal connection between nuclear structures and large-scale features has not been established unequivocally. -
Observations of Comet IRAS-Araki-Alcock (1983D) at La Silla T
- 12 the visual by 1.3 mag). Like for the other SOor variables we M explain this particular finding by the very high mass loss (M = Bol 5 6.10- M0 yr-') during outburst. The variations in the visual are caused by bolometric flux redistribution in the envelope whilst -10 the bolometric luminosity remains practically constant. The location of R127 in the Hertzsprung-Russell diagram together with the other two known SOor variables of the LMC -B are shown in fig. 8. We note that Walborn classified R127 as an Of or alterna tively as a late WN-type star. This indicates that the star is a late Of star evolving right now towards a WN star. Since we have -6 detected an SOor-type outburst of this star we conclude that this transition is not a smooth one but is instead accompanied '.8 '.6 4.0 3.6 by the occasional ejection of dense envelopes. Fig. 8: Location of the newly discovered S Dar variable R 127 in the References Hertzsprung-Russell diagram in comparison with the other two estab lished SOor variables of the LMG. Also included in the figure is the Conti, P. S.: 1976, Mem. Soc. Roy. Sei. Liege 9,193. upper envelope of known stellar absolute bolometric magnitudes as Dunean, J. C.: 1922, Publ. Astron. Soc. Pacific 34, 290. derived byHumphreys andDavidson (1979). The approximateposition Hubble, E., Sandage, A.: 1953, Astrophys. J. 118, 353. o( the late WN-type stars is also given. Humphreys, R. M., Davidson, K.: 1979, Astrophys. J. 232,409. Lamers, H. -
CMB Telescopes and Optical Systems to Appear In: Planets, Stars and Stellar Systems (PSSS) Volume 1: Telescopes and Instrumentation
CMB Telescopes and Optical Systems To appear in: Planets, Stars and Stellar Systems (PSSS) Volume 1: Telescopes and Instrumentation Shaul Hanany ([email protected]) University of Minnesota, School of Physics and Astronomy, Minneapolis, MN, USA, Michael Niemack ([email protected]) National Institute of Standards and Technology and University of Colorado, Boulder, CO, USA, and Lyman Page ([email protected]) Princeton University, Department of Physics, Princeton NJ, USA. March 26, 2012 Abstract The cosmic microwave background radiation (CMB) is now firmly established as a funda- mental and essential probe of the geometry, constituents, and birth of the Universe. The CMB is a potent observable because it can be measured with precision and accuracy. Just as importantly, theoretical models of the Universe can predict the characteristics of the CMB to high accuracy, and those predictions can be directly compared to observations. There are multiple aspects associated with making a precise measurement. In this review, we focus on optical components for the instrumentation used to measure the CMB polarization and temperature anisotropy. We begin with an overview of general considerations for CMB ob- servations and discuss common concepts used in the community. We next consider a variety of alternatives available for a designer of a CMB telescope. Our discussion is guided by arXiv:1206.2402v1 [astro-ph.IM] 11 Jun 2012 the ground and balloon-based instruments that have been implemented over the years. In the same vein, we compare the arc-minute resolution Atacama Cosmology Telescope (ACT) and the South Pole Telescope (SPT). CMB interferometers are presented briefly. We con- clude with a comparison of the four CMB satellites, Relikt, COBE, WMAP, and Planck, to demonstrate a remarkable evolution in design, sensitivity, resolution, and complexity over the past thirty years. -
World Space Observatory %Uf02d Ultraviolet Remains Very Relevant
WORLD SPACE OBSERVATORY-ULTRAVIOLET Boris Shustov, Ana Inés Gómez de Castro, Mikhail Sachkov UV observatories aperture pointing mode , Å OAO-2 1968.12 - 1973.01 20 sp is 1000-4250 TD-1A 1972.03 - 1974.05 28 s is 1350-2800+ OAO-3 1972.08 - 1981.02 80 p s 900-3150 ANS 1974.08 - 1977.06 22 p s 1500-3300+ IUE 1978.01 - 1996.09 45 p s 1150-3200 ASTRON 1983.03 - 1989.06 80 p s 1100-3500+ EXOSAT 1983.05 - 1986. 2x30 p is 250+ ROSAT 1990.06 - 1999.02 84 sp i 60- 200+ HST 1990.04 - 240 p isp 1150-10000 EUVE 1992.06 - 2001.01 12 sp is 70- 760 ALEXIS 1993.04 - 2005.04 35 s i 130- 186 MSX 1996.04 - 2003 50 s i 1100-9000+ FUSE 1999.06 - 2007.07 39х35 (4) p s 905-1195 XMM 1999.12 - 30 p is 1700-5500 GALEX 2003.04 - 2013.06 50 sp is 1350-2800 SWIFT 2004.11 - 30 p i 1700-6500 2 ASTROSAT/UVIT UVIT - UltraViolet Imaging Telescopes (on the ISRO Astrosat observatory, launch 2015); Two 40cm telescopes: FUV and NUV, FOV 0.5 degrees, resolution ~1” Next talk by John Hutchings! 3 4 ASTRON (1983 – 1989) ASTRON is an UV space observatory with 80 cm aperture telescope equipped with a scanning spectrometer:(λλ 110-350 nm, λ ~ 2 nm) onboard. Some significant results: detection of OH (H2O) in Halley comet, UV spectroscopy of SN1987a, Pb lines in stellar spectra etc. (Photo of flight model at Lavochkin Museum).5 “Spektr” (Спектр) missions Federal Space Program (2016-2025) includes as major astrophysical projects: Spektr-R (Radioastron) – launched in 2011. -
Annexe: Summary of Soviet and Russian Space Science Missions
Contents Introduction by the authors ..................................... ix Acknowledgments ............................................ xi Glossary .................................................. xiii Terminological and translation notes ..............................xv Reference notes .............................................xvii List of tables ............................................... xix List of illustrations ......................................... xxiii List of figures .............................................xxvii 1 Early space science ........................................... 1 Space science by balloon....................................... 3 Scientific flights into the atmosphere: the Akademik series..............14 Scientific test flights with animals ................................20 The idea of a scientific Earth satellite .............................23 Scientific objectives of the first Earth satellites . ....................25 Key people .................................................25 Instead, Prosteishy Sputnik .....................................27 PS2......................................................29 Object D: the first large scientific satellite in orbit....................33 Early space science: what was learned? ............................37 References .................................................39 2 Deepening our understanding ....................................43 Following Sputnik: the MS series ................................43 Cosmos 5 and Starfish: introducing Yuri Galperin -
Small-Scale Anisotropies of the Cosmic Microwave Background: Experimental and Theoretical Perspectives
Small-Scale Anisotropies of the Cosmic Microwave Background: Experimental and Theoretical Perspectives Eric R. Switzer A DISSERTATION PRESENTED TO THE FACULTY OF PRINCETON UNIVERSITY IN CANDIDACY FOR THE DEGREE OF DOCTOR OF PHILOSOPHY RECOMMENDED FOR ACCEPTANCE BY THE DEPARTMENT OF PHYSICS [Adviser: Lyman Page] November 2008 c Copyright by Eric R. Switzer, 2008. All rights reserved. Abstract In this thesis, we consider both theoretical and experimental aspects of the cosmic microwave background (CMB) anisotropy for ℓ > 500. Part one addresses the process by which the universe first became neutral, its recombination history. The work described here moves closer to achiev- ing the precision needed for upcoming small-scale anisotropy experiments. Part two describes experimental work with the Atacama Cosmology Telescope (ACT), designed to measure these anisotropies, and focuses on its electronics and software, on the site stability, and on calibration and diagnostics. Cosmological recombination occurs when the universe has cooled sufficiently for neutral atomic species to form. The atomic processes in this era determine the evolution of the free electron abundance, which in turn determines the optical depth to Thomson scattering. The Thomson optical depth drops rapidly (cosmologically) as the electrons are captured. The radiation is then decoupled from the matter, and so travels almost unimpeded to us today as the CMB. Studies of the CMB provide a pristine view of this early stage of the universe (at around 300,000 years old), and the statistics of the CMB anisotropy inform a model of the universe which is precise and consistent with cosmological studies of the more recent universe from optical astronomy. -
Cosmic Microwave Background
1 29. Cosmic Microwave Background 29. Cosmic Microwave Background Revised August 2019 by D. Scott (U. of British Columbia) and G.F. Smoot (HKUST; Paris U.; UC Berkeley; LBNL). 29.1 Introduction The energy content in electromagnetic radiation from beyond our Galaxy is dominated by the cosmic microwave background (CMB), discovered in 1965 [1]. The spectrum of the CMB is well described by a blackbody function with T = 2.7255 K. This spectral form is a main supporting pillar of the hot Big Bang model for the Universe. The lack of any observed deviations from a 7 blackbody spectrum constrains physical processes over cosmic history at redshifts z ∼< 10 (see earlier versions of this review). Currently the key CMB observable is the angular variation in temperature (or intensity) corre- lations, and to a growing extent polarization [2–4]. Since the first detection of these anisotropies by the Cosmic Background Explorer (COBE) satellite [5], there has been intense activity to map the sky at increasing levels of sensitivity and angular resolution by ground-based and balloon-borne measurements. These were joined in 2003 by the first results from NASA’s Wilkinson Microwave Anisotropy Probe (WMAP)[6], which were improved upon by analyses of data added every 2 years, culminating in the 9-year results [7]. In 2013 we had the first results [8] from the third generation CMB satellite, ESA’s Planck mission [9,10], which were enhanced by results from the 2015 Planck data release [11, 12], and then the final 2018 Planck data release [13, 14]. Additionally, CMB an- isotropies have been extended to smaller angular scales by ground-based experiments, particularly the Atacama Cosmology Telescope (ACT) [15] and the South Pole Telescope (SPT) [16]. -
The World Space Observatory: Ultraviolet Mission: Science Program and Status Report
PROCEEDINGS OF SPIE SPIEDigitalLibrary.org/conference-proceedings-of-spie The World Space Observatory: ultraviolet mission: science program and status report Sachkov, M., Gómez de Castro, A. I., Shustov, B. M. Sachkov, A. I. Gómez de Castro, B. Shustov, "The World Space Observatory: ultraviolet mission: science program and status report," Proc. SPIE 11444, Space Telescopes and Instrumentation 2020: Ultraviolet to Gamma Ray, 1144473 (13 December 2020); doi: 10.1117/12.2562929 Event: SPIE Astronomical Telescopes + Instrumentation, 2020, Online Only Downloaded From: https://www.spiedigitallibrary.org/conference-proceedings-of-spie on 19 Jan 2021 Terms of Use: https://www.spiedigitallibrary.org/terms-of-use The World Space Observatory - Ultraviolet mission: science program and status report M. Sachkov*a , A.I. Gómez de Castrob, B. Shustova aInstitute of Astronomy of Russian Academy of Sciences, Pyatnitskaya str., 48, Moscow, 119017, Russia; bAEGORA Research Group, Fac. CC. Matematicas, Universidad Complutense, Plaza de Ciencias 3, 28040, Madrid, Spain ABSTRACT A general description of the international space mission "Spectr-UF" (World Space Observatory-Ultraviolet) is given. The project is aimed to create a large space telescope to work in the UV wavelength domain (115 - 310 nm). In the Federal Space Program of Russia for 2016-2025 the launch of the project is scheduled for 2025. We implement several important improvements: updated scientific program of the project; a new design of the Field Camera Unit instrument; corrected orbit; developed a system of collecting applications etc. This paper briefly describes the current status of the mission. Keywords: ultraviolet, spectroscopy, imaging, exoplanet, UV space telescope, WSO-UV 1. INTRODUCTION The Earth's atmosphere blocks observations of celestial objects in the ultraviolet (UV) part of the electromagnetic spectrum. -
The Status of the Hubble Space Telescope
al insights into the atmospheric struc- ture of hot stars. It is essential, although time consum- ing, to disentangle effects due to binari- ty from effects reflecting the kinematics of the stellar group (11). Especially the lack of recognition of wider binaries with an RV amplitude of the order of 10 kmls might significantly influence the conclu- sions. Hence, repetition of RV observa- tions is necessary and will in turn in- crease our knowledge on binarity in the selected young stellar groups. The spectra will in addition allow a study of stellar rotation in these star groups (12). In many respects, this project forms an extension towards the earliest spec- tral types of the key programmes of Mayor et al. and Gerbaldi et al. (de- scribed in the Messenger 56), even when the primary scientific motivation is somewhat different. In addition to the common interest in radial velocities, the stars in Sco-Cen are also observed by the Hipparcos satellite, providing space motions when combined with the RVs. Using these, we hope to reconstruct the initial minimal volumes in which the star formation occurred which gave rise to the presently expanding Sco-Cen sub- 4180 4200 4220 4240 4260 4280 groups, and to discuss the possibility of wavelength (angstrom) sequential star formation (13). Part of the CASPEC spectrum of NGC 2244-201, a 10th magnitude B 1 V star. The strongest lines are 011 4185, 011 4 190, NII 4242, 011 4254, CII 4267, a complex of 011 lines around First Results 4277A, 011 4283, Slll4285 and 011 4286. Strictly within the frame of the key programme, the first spectra have been obtained on 3 nights in May 1990. -
The UV Perspective of Low-Mass Star Formation
galaxies Review The UV Perspective of Low-Mass Star Formation P. Christian Schneider 1,* , H. Moritz Günther 2 and Kevin France 3 1 Hamburger Sternwarte, University of Hamburg, 21029 Hamburg, Germany 2 Massachusetts Institute of Technology, Kavli Institute for Astrophysics and Space Research; Cambridge, MA 02109, USA; [email protected] 3 Department of Astrophysical and Planetary Sciences Laboratory for Atmospheric and Space Physics, University of Colorado, Denver, CO 80203, USA; [email protected] * Correspondence: [email protected] Received: 16 January 2020; Accepted: 29 February 2020; Published: 21 March 2020 Abstract: The formation of low-mass (M? . 2 M ) stars in molecular clouds involves accretion disks and jets, which are of broad astrophysical interest. Accreting stars represent the closest examples of these phenomena. Star and planet formation are also intimately connected, setting the starting point for planetary systems like our own. The ultraviolet (UV) spectral range is particularly suited for studying star formation, because virtually all relevant processes radiate at temperatures associated with UV emission processes or have strong observational signatures in the UV range. In this review, we describe how UV observations provide unique diagnostics for the accretion process, the physical properties of the protoplanetary disk, and jets and outflows. Keywords: star formation; ultraviolet; low-mass stars 1. Introduction Stars form in molecular clouds. When these clouds fragment, localized cloud regions collapse into groups of protostars. Stars with final masses between 0.08 M and 2 M , broadly the progenitors of Sun-like stars, start as cores deeply embedded in a dusty envelope, where they can be seen only in the sub-mm and far-IR spectral windows (so-called class 0 sources). -
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.