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X-Ray Flux and Spectral Variability of Blazar H 2356-309
galaxies Article X-ray Flux and Spectral Variability of Blazar H 2356-309 Kiran A. Wani and Haritma Gaur * Aryabhatta Research Institute of Observational Sciences (ARIES), Manora Peak, Nainital 263002, India; [email protected] * Correspondence: [email protected] Received: 6 July 2020; Accepted: 31 July 2020; Published: date Abstract: We present the results of timing and spectral analysis of the blazar H 2356-309 using XMM-Newton observations. This blazar is observed during 13 June 2005–24 December 2013 in total nine observations. Five of the observations show moderate flux variability with amplitude 1.7–2.2%. We search for the intra-day variability timescales in these five light curves, but did not find in any of them. The fractional variability amplitude is generally lower in the soft bands than in the hard bands, which is attributed to the energy dependent synchrotron emission. Using the hardness ratio analysis, we search for the X-ray spectral variability along with flux variability in this source. However, we did not find any significant spectral variability on intra-day timescales. We also investigate the X-ray spectral curvature of blazar H 2356-309 and found that six of our observations are well described by the log parabolic model with α = 1.99–2.15 and β = 0.03–0.18. Three of our observations are well described by power law model. The break energy of the X-ray spectra varies between 1.97–2.31 keV. We investigate the correlation between various parameters that are derived from log parabolic model and their implications are discussed. -
1989Aj 97. . 51 Om the Astronomical Journal Volume 97, Number 2 February 1989 Iccd Speckle Observations of Binary Stars. Iv
OM 51 . THE ASTRONOMICAL JOURNAL VOLUME 97, NUMBER 2 FEBRUARY 1989 97. ICCD SPECKLE OBSERVATIONS OF BINARY STARS. IV. MEASUREMENTS DURING 1986-1988 FROM THE KITT PEAK 4 m TELESCOPE Harold A. McAlister,a) William I. Hartkopf,a) James R. Sowell,10 1989AJ and Edmund G. Dombrowski“’ Center for High Angular Resolution Astronomy, Georgia State University, Atlanta, Georgia 30303 OttoG. Franz3) Lowell Observatory, Flagstaff, Arizona 86001 Received 29 August 1988; revised 12 October 1988 ABSTRACT One thousand five hundred and fifty measurements of 1006 binary star systems observed mostly during 1986 through mid-1988 by means of speckle interferometry with the KPNO 4 m telescope are present- ed. Twenty-one systems are directly resolved for the first time, including new components to the cool supergiant a Her A and the Pleiades shell star Pleione. A continuing survey of The Bright Star Cata- logue yielded eight new binaries from 293 bright stars observed. Corrections to speckle measures from the GSU/CHARA ICCD speckle camera previously published are presented and discussed. I. INTRODUCTION for the 1983-1984 data is due to the somewhat lower quality This paper presents further results from a continuing pro- of the calibration data available for that particular time peri- gram of binary star speckle interferometry carried out at the od. We now adopt a calibration based upon the mean of all 4 m Mayall telescope at Kitt Peak National Observatory. A the scale and orientation measurements that we have deter- detailed description of the observational technique and in- mined since the initiation of our ICCD speckle-camera sys- strumentation, and of the methods of data reduction, analy- tem. -
Unknown Amorphous Carbon II. LRS SPECTRA the Sample Consists Of
Table I A summary of the spectral -features observed in the LRS spectra of the three groups o-f carbon stars. The de-finition o-f the groups is given in the text. wavelength Xmax identification Group I B - 12 urn E1 9.7 M™ Silicate 12 - 23 jim E IB ^m Silicate Group II < 8.5 M"i A C2H2 CS? 12 - 16 f-i/n A 13.7 - 14 Mm C2H2 HCN? 8 - 10 Mm E 8.6 M"i Unknown 10 - 13 Mm E 11.3 - 11 .7 M«> SiC Group III 10 - 13 MJn E 11.3 - 11 .7 tun SiC B - 23 Htn C Amorphous carbon 1 The letter in this column indicates the nature o-f the -feature: A = absorption; E = emission; C indicates the presence of continuum opacity. II. LRS SPECTRA The sample consists of 304 carbon stars with entries in the LRS catalog (Papers I-III). The LRS spectra have been divided into three groups. Group I consists of nine stars with 9.7 and 18 tun silicate features in their LRS spectra pointing to oxygen-rich dust in the circumstellar shell. These sources are discussed in Paper I. The remaining stars all have spectra with carbon-rich dust features. Using NIR photometry we have shown that in the group II spectra the stellar photosphere is the dominant continuum. The NIR color temperature is of the order of 25OO K. Paper II contains a discussion of sources with this class of spectra. The continuum in the group III spectra is probably due to amorphous carbon dust. -
Relativistic Jets in Active Galactic Nuclei Und Microquasars
SSRv manuscript No. (will be inserted by the editor) Relativistic Jets in Active Galactic Nuclei and Microquasars Gustavo E. Romero · M. Boettcher · S. Markoff · F. Tavecchio Received: date / Accepted: date Abstract Collimated outflows (jets) appear to be a ubiquitous phenomenon associated with the accretion of material onto a compact object. Despite this ubiquity, many fundamental physics aspects of jets are still poorly un- derstood and constrained. These include the mechanism of launching and accelerating jets, the connection between these processes and the nature of the accretion flow, and the role of magnetic fields; the physics responsible for the collimation of jets over tens of thousands to even millions of gravi- tational radii of the central accreting object; the matter content of jets; the location of the region(s) accelerating particles to TeV (possibly even PeV and EeV) energies (as evidenced by γ-ray emission observed from many jet sources) and the physical processes responsible for this particle accelera- tion; the radiative processes giving rise to the observed multi-wavelength emission; and the topology of magnetic fields and their role in the jet colli- mation and particle acceleration processes. This chapter reviews the main knowns and unknowns in our current understanding of relativistic jets, in the context of the main model ingredients for Galactic and extragalactic jet sources. It discusses aspects specific to active Galactic nuclei (especially Gustavo E. Romero Instituto Argentino de Radioastronoma (IAR), C.C. No. 5, 1894, Buenos Aires, Argentina E-mail: [email protected] M. Boettcher Centre for Space Research, Private Bag X6001, North-West University, Potchef- stroom, 2520, South Africa E-mail: [email protected] S. -
The NTT Provides the Deepest Look Into Space 6
The NTT Provides the Deepest Look Into Space 6. A. PETERSON, Mount Stromlo Observatory,Australian National University, Canberra S. D'ODORICO, M. TARENGHI and E. J. WAMPLER, ESO The ESO New Technology Telescope r on La Silla has again proven its extraor- - dinary abilities. It has now produced the "deepest" view into the distant regions of the Universe ever obtained with ground- or space-based telescopes. Figure 1 : This picture is a reproduction of a I.1 x 1.1 arcmin portion of a composite im- age of forty-one 10-minute exposures in the V band of a field at high galactic latitude in the constellation of Sextans (R.A. loh 45'7 Decl. -0' 143. The individual images were obtained with the EMMI imager/spectrograph at the Nas- myth focus of the ESO 3.5-m New Technolo- gy Telescope using a 1000 x 1000 pixel Thomson CCD. This combination gave a full field of 7.6 x 7.6 arcmin and a pixel size of 0.44 arcsec. The average seeing during these exposures was 1.0 arcsec. The telescope was offset between the indi- vidual exposures so that the sky background could be used to flat-field the frame. This procedure also removed the effects of cos- mic rays and blemishes in the CCD. More than 97% of the objects seen in this sub- field are galaxies. For the brighter galax- ies, there is good agreement between the galaxy counts of Tyson (1988, Astron. J., 96, 1) and the NTT counts for the brighter galax- ies. -
Annual Report 2016–2017 AAVSO
AAVSO The American Association of Variable Star Observers Annual Report 2016–2017 AAVSO Annual Report 2012 –2013 The American Association of Variable Star Observers AAVSO Annual Report 2016–2017 The American Association of Variable Star Observers 49 Bay State Road Cambridge, MA 02138-1203 USA Telephone: 617-354-0484 Fax: 617-354-0665 email: [email protected] website: https://www.aavso.org Annual Report Website: https://www.aavso.org/annual-report On the cover... At the 2017 AAVSO Annual Meeting.(clockwise from upper left) Knicole Colon, Koji Mukai, Dennis Conti, Kristine Larsen, Joey Rodriguez; Rachid El Hamri, Andy Block, Jane Glanzer, Erin Aadland, Jamin Welch, Stella Kafka; and (clockwise from upper left) Joey Rodriguez, Knicole Colon, Koji Mukai, Frans-Josef “Josch” Hambsch, Chandler Barnes. Picture credits In additon to images from the AAVSO and its archives, the editors gratefully acknowledge the following for their image contributions: Glenn Chaple, Shawn Dvorak, Mary Glennon, Bill Goff, Barbara Harris, Mario Motta, NASA, Gary Poyner, Msgr. Ronald Royer, the Mary Lea Shane Archives of the Lick Observatory, Chris Stephan, and Wheatley, et al. 2003, MNRAS, 345, 49. Table of Contents 1. About the AAVSO Vision and Mission Statement 1 About the AAVSO 1 What We Do 2 What Are Variable Stars? 3 Why Observe Variable Stars? 3 The AAVSO International Database 4 Observing Variable Stars 6 Services to Astronomy 7 Education and Outreach 9 2. The Year in Review Introduction 11 The 106th AAVSO Spring Membership Meeting, Ontario, California 11 The -
Arxiv:2105.11583V2 [Astro-Ph.EP] 2 Jul 2021 Keck-HIRES, APF-Levy, and Lick-Hamilton Spectrographs
Draft version July 6, 2021 Typeset using LATEX twocolumn style in AASTeX63 The California Legacy Survey I. A Catalog of 178 Planets from Precision Radial Velocity Monitoring of 719 Nearby Stars over Three Decades Lee J. Rosenthal,1 Benjamin J. Fulton,1, 2 Lea A. Hirsch,3 Howard T. Isaacson,4 Andrew W. Howard,1 Cayla M. Dedrick,5, 6 Ilya A. Sherstyuk,1 Sarah C. Blunt,1, 7 Erik A. Petigura,8 Heather A. Knutson,9 Aida Behmard,9, 7 Ashley Chontos,10, 7 Justin R. Crepp,11 Ian J. M. Crossfield,12 Paul A. Dalba,13, 14 Debra A. Fischer,15 Gregory W. Henry,16 Stephen R. Kane,13 Molly Kosiarek,17, 7 Geoffrey W. Marcy,1, 7 Ryan A. Rubenzahl,1, 7 Lauren M. Weiss,10 and Jason T. Wright18, 19, 20 1Cahill Center for Astronomy & Astrophysics, California Institute of Technology, Pasadena, CA 91125, USA 2IPAC-NASA Exoplanet Science Institute, Pasadena, CA 91125, USA 3Kavli Institute for Particle Astrophysics and Cosmology, Stanford University, Stanford, CA 94305, USA 4Department of Astronomy, University of California Berkeley, Berkeley, CA 94720, USA 5Cahill Center for Astronomy & Astrophysics, California Institute of Technology, Pasadena, CA 91125, USA 6Department of Astronomy & Astrophysics, The Pennsylvania State University, 525 Davey Lab, University Park, PA 16802, USA 7NSF Graduate Research Fellow 8Department of Physics & Astronomy, University of California Los Angeles, Los Angeles, CA 90095, USA 9Division of Geological and Planetary Sciences, California Institute of Technology, Pasadena, CA 91125, USA 10Institute for Astronomy, University of Hawai`i, -
2014-08 AUG.Pdf
August First Light Newsletter 1 message August, 2014 Issue 122 AlachuaAstronomyClub.org North Central Florida's Amateur Astronomy Club Serving Alachua County since 1987 BREAKING NEWS -- ROSETTA HAS JUST ARRIVED AT COMET 67/P Member Member Astronomical League Initiated in late 1993 by Europe and the USA, and launched in 2004, the International Rosetta Mission is an historic first: Send a spacecraft to chase and orbit a comet, ride along as the comet plunges sun ward to learn how a frozen comet transforms by the Sun's warmth, and dispatch a controlled lander to make in situ measurements and make first images Member from a comet's surface. NASA Night Sky Network Ten years later Rosetta has now arrived at Comet 67P/Churyumov- Gerasimenko and just successfully made orbit today, 2014 August 6! Unfortunately, global events have foreshadowed this memorable event and news media have largely ignored this impressive space mission. AAC Member photo: The Rosetta comet mission may be the beginning of a story that will tell more about us -- both about our origins and evolution. (Hence, its name "rosetta" for the black basalt stone with inscriptions giving the first clues to deciphering Egyptian hieroglyphics.) Pictures received over past weeks are remarkable with the latest in the past 24 hours showing awesome and incredible detail including views that show the comet is a connected binary object rotating as a unit in 12 hours. Anyone see the glorious pairing of Venus and Jupiter this morning (2016 Aug. 18)? For images see http://www.esa.int/ spaceinimages/Missions/ Except when Mars is occasionally brighter Rosetta than Jupiter, these two planets are the brightest nighttime sky objects (discounting Example Image (Aug. -
UC Irvine UC Irvine Previously Published Works
UC Irvine UC Irvine Previously Published Works Title Astrophysics in 2006 Permalink https://escholarship.org/uc/item/5760h9v8 Journal Space Science Reviews, 132(1) ISSN 0038-6308 Authors Trimble, V Aschwanden, MJ Hansen, CJ Publication Date 2007-09-01 DOI 10.1007/s11214-007-9224-0 License https://creativecommons.org/licenses/by/4.0/ 4.0 Peer reviewed eScholarship.org Powered by the California Digital Library University of California Space Sci Rev (2007) 132: 1–182 DOI 10.1007/s11214-007-9224-0 Astrophysics in 2006 Virginia Trimble · Markus J. Aschwanden · Carl J. Hansen Received: 11 May 2007 / Accepted: 24 May 2007 / Published online: 23 October 2007 © Springer Science+Business Media B.V. 2007 Abstract The fastest pulsar and the slowest nova; the oldest galaxies and the youngest stars; the weirdest life forms and the commonest dwarfs; the highest energy particles and the lowest energy photons. These were some of the extremes of Astrophysics 2006. We attempt also to bring you updates on things of which there is currently only one (habitable planets, the Sun, and the Universe) and others of which there are always many, like meteors and molecules, black holes and binaries. Keywords Cosmology: general · Galaxies: general · ISM: general · Stars: general · Sun: general · Planets and satellites: general · Astrobiology · Star clusters · Binary stars · Clusters of galaxies · Gamma-ray bursts · Milky Way · Earth · Active galaxies · Supernovae 1 Introduction Astrophysics in 2006 modifies a long tradition by moving to a new journal, which you hold in your (real or virtual) hands. The fifteen previous articles in the series are referenced oc- casionally as Ap91 to Ap05 below and appeared in volumes 104–118 of Publications of V. -
Astronomy Binder
Astronomy Binder Bloomington High School South 2011 Contents 1 Astronomical Distances 2 1.1 Geometric Methods . 2 1.2 Spectroscopic Methods . 4 1.3 Standard Candle Methods . 4 1.4 Cosmological Redshift . 5 1.5 Distances to Galaxies . 5 2 Age and Size 6 2.1 Measuring Age . 6 2.2 Measuring Size . 7 3 Variable Stars 7 3.1 Pulsating Variable Stars . 7 3.1.1 Cepheid Variables . 7 3.1.2 RR Lyrae Variables . 8 3.1.3 RV Tauri Variables . 8 3.1.4 Long Period/Semiregular Variables . 8 3.2 Binary Variables . 8 3.3 Cataclysmic Variables . 11 3.3.1 Classical Nova . 11 3.3.2 Recurrent Novae . 11 3.3.3 Dwarf Novae (U Geminorum) . 11 3.3.4 X-Ray Binary . 11 3.3.5 Polar (AM Herculis) star . 12 3.3.6 Intermediate Polar (DQ Herculis) star . 12 3.3.7 Super Soft Source (SSS) . 12 3.3.8 VY Sculptoris stars . 12 3.3.9 AM Canum Venaticorum stars . 12 3.3.10 SW Sextantis stars . 13 3.3.11 Symbiotic Stars . 13 3.3.12 Pulsating White Dwarfs . 13 4 Galaxy Classification 14 4.1 Elliptical Galaxies . 14 4.2 Spirals . 15 4.3 Classification . 16 4.4 The Milky Way Galaxy (MWG . 19 4.4.1 Scale Height . 19 4.4.2 Magellanic Clouds . 20 5 Galaxy Interactions 20 6 Interstellar Medium 21 7 Active Galactic Nuclei 22 7.1 AGN Equations . 23 1 8 Spectra 25 8.1 21 cm line . 26 9 Black Holes 26 9.1 Stellar Black Holes . -
Fy10 Budget by Program
AURA/NOAO FISCAL YEAR ANNUAL REPORT FY 2010 Revised Submitted to the National Science Foundation March 16, 2011 This image, aimed toward the southern celestial pole atop the CTIO Blanco 4-m telescope, shows the Large and Small Magellanic Clouds, the Milky Way (Carinae Region) and the Coal Sack (dark area, close to the Southern Crux). The 33 “written” on the Schmidt Telescope dome using a green laser pointer during the two-minute exposure commemorates the rescue effort of 33 miners trapped for 69 days almost 700 m underground in the San Jose mine in northern Chile. The image was taken while the rescue was in progress on 13 October 2010, at 3:30 am Chilean Daylight Saving time. Image Credit: Arturo Gomez/CTIO/NOAO/AURA/NSF National Optical Astronomy Observatory Fiscal Year Annual Report for FY 2010 Revised (October 1, 2009 – September 30, 2010) Submitted to the National Science Foundation Pursuant to Cooperative Support Agreement No. AST-0950945 March 16, 2011 Table of Contents MISSION SYNOPSIS ............................................................................................................ IV 1 EXECUTIVE SUMMARY ................................................................................................ 1 2 NOAO ACCOMPLISHMENTS ....................................................................................... 2 2.1 Achievements ..................................................................................................... 2 2.2 Status of Vision and Goals ................................................................................ -
Dr. Jan-Uwe Ness European Space Agency ESAC, Apartado 78 28691 Villanueva De La Ca˜Nada, Madrid, Spain Born 28 September, 1970, Germany
Curriculum Vitae Dr. Jan-Uwe Ness European Space Agency ESAC, Apartado 78 28691 Villanueva de la Ca˜nada, Madrid, Spain born 28 September, 1970, Germany Positions since 2009 European Space Agency since 2018 Operations Scientist in XMM-Newton and INTEGRAL since 2019 ESAC Research Fellowship Coordinator since 2018 Coordinator for Virtual Observatory (VO) Protocols since 2020 Member of Staff Association Committee (SAC); also 2013-2017 For details, see extra sheet 2006-2008 Arizona State University, Phoenix, AZ, USA Chandra Fellow Scientific research in X-ray astronomy 2004-2006 University of Oxford, UK Research Associate at Dep. of Theor. Physics 1999-2004 University of Hamburg, Germany 2002-2004 Post-doc at Hamburger Sternwarte 1999-2002 PhD Student at Hamburger Sternwarte 1997-1998 University of Kiel, Germany Teaching Assistant Education May 2002 Ph.D. in Astrophysics at University of Hamburg, Germany PhD Thesis on High-resolution X-ray plasma diagnostics of stellar coronae Dec 1998 Graduation in Astrophysics at University of Kiel, Germany Diploma Thesis on N-body Simulations of Interacting Galaxies May 1991 Graduation from High School with Abitur in Germany 1988-1989 High School in Renton, Washington, USA Languages German Mother tongue English Fluent Spaninsh Fluent French Poor ESA Training 2020 Effective Interpersonal Communication (registered for Oct.) SAC Newcomers 2019 Conflict Management 2018 Professional Networking Winning Hearts and Minds 2017 Fundamentals of People Management Scientific Approaches to Creativity for Professionals 2016 IDP (Internal Development Process), ICP (Internal Contact Person), Advanced Reading Skills 2015 Introduction to Spacecraft Operations Space in a Nutshell 2014 Cost Estimating, Bootcamp on Scientific Programming 2013 Advanced IDL course 2012 Assertiveness at work 2011 Space Systems Engineering 2009 Presentation Skills Stipends 2008 Ramon y Cajal: 5 years offered but declined to take ESA position and 2005 Chandra Fellowship: 3 years with Prof.