Globular Cluster X-Ray Sources
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Astronomie in Theorie Und Praxis 8. Auflage in Zwei Bänden Erik Wischnewski
Astronomie in Theorie und Praxis 8. Auflage in zwei Bänden Erik Wischnewski Inhaltsverzeichnis 1 Beobachtungen mit bloßem Auge 37 Motivation 37 Hilfsmittel 38 Drehbare Sternkarte Bücher und Atlanten Kataloge Planetariumssoftware Elektronischer Almanach Sternkarten 39 2 Atmosphäre der Erde 49 Aufbau 49 Atmosphärische Fenster 51 Warum der Himmel blau ist? 52 Extinktion 52 Extinktionsgleichung Photometrie Refraktion 55 Szintillationsrauschen 56 Angaben zur Beobachtung 57 Durchsicht Himmelshelligkeit Luftunruhe Beispiel einer Notiz Taupunkt 59 Solar-terrestrische Beziehungen 60 Klassifizierung der Flares Korrelation zur Fleckenrelativzahl Luftleuchten 62 Polarlichter 63 Nachtleuchtende Wolken 64 Haloerscheinungen 67 Formen Häufigkeit Beobachtung Photographie Grüner Strahl 69 Zodiakallicht 71 Dämmerung 72 Definition Purpurlicht Gegendämmerung Venusgürtel Erdschattenbogen 3 Optische Teleskope 75 Fernrohrtypen 76 Refraktoren Reflektoren Fokus Optische Fehler 82 Farbfehler Kugelgestaltsfehler Bildfeldwölbung Koma Astigmatismus Verzeichnung Bildverzerrungen Helligkeitsinhomogenität Objektive 86 Linsenobjektive Spiegelobjektive Vergütung Optische Qualitätsprüfung RC-Wert RGB-Chromasietest Okulare 97 Zusatzoptiken 100 Barlow-Linse Shapley-Linse Flattener Spezialokulare Spektroskopie Herschel-Prisma Fabry-Pérot-Interferometer Vergrößerung 103 Welche Vergrößerung ist die Beste? Blickfeld 105 Lichtstärke 106 Kontrast Dämmerungszahl Auflösungsvermögen 108 Strehl-Zahl Luftunruhe (Seeing) 112 Tubusseeing Kuppelseeing Gebäudeseeing Montierungen 113 Nachführfehler -
First Scientific Results with the VLT in Visitor and Service Modes
No. 98 – December 1999 First Scientific Results with the VLT in Visitor and Service Modes Starting with this issue, The Messenger will regularly include scientific results obtained with the VLT. One of the results reported in this issue is a study of NGC 3603, the most massive visible H II region in the Galaxy, with VLT/ISAAC in the near-infrared Js, H, and Ks-bands and HST/WFPC2 at Hα and [N II] wavelengths. These VLT observations are the most sensitive near-infrared observations made to date of a dense starburst region, allowing one to in- vestigate with unprecedented quality its low-mass stellar population. The sensitivity limit to stars detected in all three bands corresponds to 0.1 M0 for a pre-main-sequence star of age 0.7 Myr. The observations clearly show that sub-solar-mass stars down to at least 0.1 M0 do form in massive starbursts (from B. Brandl, W. Brandner, E.K. Grebel and H. Zinnecker, page 46). Js versus Js–Ks colour-magnitude diagrams of NGC 3603. The left-hand panel contains all stars detected in all three wave- bands in the entire field of view (3.4′×3.4′, or 6 pc × 6 pc); the centre panel shows the field stars at r > 75″ (2.25 pc) around the cluster, and the right-hand panel shows the cluster population within r < 33″ (1pc) with the field stars statistically subtracted. The dashed horizontal line (left-hand panel) indicates the detection limit of the previous most sensitive NIR study (Eisenhauer et al. -
Spatial Distribution of Galactic Globular Clusters: Distance Uncertainties and Dynamical Effects
Juliana Crestani Ribeiro de Souza Spatial Distribution of Galactic Globular Clusters: Distance Uncertainties and Dynamical Effects Porto Alegre 2017 Juliana Crestani Ribeiro de Souza Spatial Distribution of Galactic Globular Clusters: Distance Uncertainties and Dynamical Effects Dissertação elaborada sob orientação do Prof. Dr. Eduardo Luis Damiani Bica, co- orientação do Prof. Dr. Charles José Bon- ato e apresentada ao Instituto de Física da Universidade Federal do Rio Grande do Sul em preenchimento do requisito par- cial para obtenção do título de Mestre em Física. Porto Alegre 2017 Acknowledgements To my parents, who supported me and made this possible, in a time and place where being in a university was just a distant dream. To my dearest friends Elisabeth, Robert, Augusto, and Natália - who so many times helped me go from "I give up" to "I’ll try once more". To my cats Kira, Fen, and Demi - who lazily join me in bed at the end of the day, and make everything worthwhile. "But, first of all, it will be necessary to explain what is our idea of a cluster of stars, and by what means we have obtained it. For an instance, I shall take the phenomenon which presents itself in many clusters: It is that of a number of lucid spots, of equal lustre, scattered over a circular space, in such a manner as to appear gradually more compressed towards the middle; and which compression, in the clusters to which I allude, is generally carried so far, as, by imperceptible degrees, to end in a luminous center, of a resolvable blaze of light." William Herschel, 1789 Abstract We provide a sample of 170 Galactic Globular Clusters (GCs) and analyse its spatial distribution properties. -
Globular Clusters in the Inner Galaxy Classified from Dynamical Orbital
MNRAS 000,1{17 (2019) Preprint 14 November 2019 Compiled using MNRAS LATEX style file v3.0 Globular clusters in the inner Galaxy classified from dynamical orbital criteria Angeles P´erez-Villegas,1? Beatriz Barbuy,1 Leandro Kerber,2 Sergio Ortolani3 Stefano O. Souza 1 and Eduardo Bica,4 1Universidade de S~aoPaulo, IAG, Rua do Mat~ao 1226, Cidade Universit´aria, S~ao Paulo 05508-900, Brazil 2Universidade Estadual de Santa Cruz, Rodovia Jorge Amado km 16, Ilh´eus 45662-000, Brazil 3Dipartimento di Fisica e Astronomia `Galileo Galilei', Universit`adi Padova, Vicolo dell'Osservatorio 3, Padova, I-35122, Italy 4Universidade Federal do Rio Grande do Sul, Departamento de Astronomia, CP 15051, Porto Alegre 91501-970, Brazil Accepted XXX. Received YYY; in original form ZZZ ABSTRACT Globular clusters (GCs) are the most ancient stellar systems in the Milky Way. There- fore, they play a key role in the understanding of the early chemical and dynamical evolution of our Galaxy. Around 40% of them are placed within ∼ 4 kpc from the Galactic center. In that region, all Galactic components overlap, making their disen- tanglement a challenging task. With Gaia DR2, we have accurate absolute proper mo- tions for the entire sample of known GCs that have been associated with the bulge/bar region. Combining them with distances, from RR Lyrae when available, as well as ra- dial velocities from spectroscopy, we can perform an orbital analysis of the sample, employing a steady Galactic potential with a bar. We applied a clustering algorithm to the orbital parameters apogalactic distance and the maximum vertical excursion from the plane, in order to identify the clusters that have high probability to belong to the bulge/bar, thick disk, inner halo, or outer halo component. -
Global Fitting of Globular Cluster Age Indicators
A&A 456, 1085–1096 (2006) Astronomy DOI: 10.1051/0004-6361:20065133 & c ESO 2006 Astrophysics Global fitting of globular cluster age indicators F. Meissner1 and A. Weiss1 Max-Planck-Institut für Astrophysik, Karl-Schwarzschild-Str. 1, 85748 Garching, Germany e-mail: [meissner;weiss]@mpa-garching.mpg.de Received 3 March 2006 / Accepted 12 June 2006 ABSTRACT Context. Stellar models and the methods for the age determinations of globular clusters are still in need of improvement. Aims. We attempt to obtain a more objective method of age determination based on cluster diagrams, avoiding the introduction of biases due to the preference of one single age indicator. Methods. We compute new stellar evolutionary tracks and derive the dependence of age indicating points along the tracks and isochrone – such as the turn-off or bump location – as a function of age and metallicity. The same critical points are identified in the colour-magnitude diagrams of globular clusters from a homogeneous database. Several age indicators are then fitted simultaneously, and the overall best-fitting isochrone is selected to determine the cluster age. We also determine the goodness-of-fit for different sets of indicators to estimate the confidence level of our results. Results. We find that our isochrones provide no acceptable fit for all age indicators. In particular, the location of the bump and the brightness of the tip of the red giant branch are problematic. On the other hand, the turn-off region is very well reproduced, and restricting the method to indicators depending on it results in trustworthy ages. Using an alternative set of isochrones improves the situation, but neither leads to an acceptable global fit. -
Arxiv:2009.10347V3 [Astro-Ph.IM] 24 Feb 2021
Draft version February 25, 2021 Typeset using LATEX twocolumn style in AASTeX63 Timing Calibration of the NuSTAR X-ray Telescope Matteo Bachetti,1, 2, ∗ Craig B. Markwardt,3 Brian W. Grefenstette,2 Eric V. Gotthelf,4 Lucien Kuiper,5 Didier Barret,6 W. Rick Cook,2 Andrew Davis,2 Felix Furst¨ ,7 Karl Forster,2 Fiona A. Harrison,2 Kristin K. Madsen,2, 3 Hiromasa Miyasaka,2 Bryce Roberts,8 John A. Tomsick,8 and Dominic J. walton9 1INAF-Osservatorio Astronomico di Cagliari, via della Scienza 5, I-09047 Selargius, Italy 2Space Radiation Laboratory, Caltech, 1200 E California Blvd, Pasadena, CA 91125 3Astrophysics Science Division, NASA Goddard Space Flight Center, Greenbelt, MD 20771, USA 4Columbia Astrophysics Laboratory, Columbia University, 550 West 120th Street, New York, NY 10027-6601, USA 5SRON Netherlands Institute for Space Research, Sorbonnelaan 2, NL-3584 CA Utrecht, the Netherlands 6IRAP, Universit´ede Toulouse, CNRS, UPS, CNES, 9, Avenue du Colonel Roche, BP 44346, F-31028 Toulouse Cedex 4, France 7European Space Astronomy Centre (ESA/ESAC), Operations Department, Villanueva de la Ca~nada(Madrid), Spain 8Space Sciences Laboratory, 7 Gauss Way, University of California, Berkeley, CA 94720-7450, USA 9Institute of Astronomy, University of Cambridge, Madingley Road, Cambridge CB3 0HA, UK (Received January 1, 2018; Revised January 7, 2018; Accepted February 25, 2021) Submitted to ApJ ABSTRACT The Nuclear Spectroscopic Telescope Array (NuSTAR) mission is the first focusing X-ray telescope in the hard X-ray (3-79 keV) band. Among the phenomena that can be studied in this energy band, some require high time resolution and stability: rotation-powered and accreting millisecond pulsars, fast variability from black holes and neutron stars, X-ray bursts, and more. -
Pos(MQW7)004 Ce
Hard (State) Problems PoS(MQW7)004 John A. Tomsick Space Science Laboratory, 7 Gauss Way, University of California, Berkeley, CA 94720-7450, USA E-mail: [email protected] For microquasars, the one time when these systems exhibit steady and powerful jets is when they are in the hard state. Thus, our understanding of this state is key to learning about the disk/jet connection. Recent observational and theoretical results have led to questions about whether we really understand the physical properties of this state, and even our basic picture of this state is uncertain. Here, I discuss some of the recent developmentsand possible problems with our under- standing of this state. Overall, it appears that the strongest challenge to the standard truncated disk picture is the detection of broad iron features in the X-ray spectra, and it seems that either there is a problem with the truncated disk picture or there is a problem with the relativistic reflection models used to explain the broad iron features. VII Microquasar Workshop: Microquasars and Beyond September 1-5 2008 Foca, Izmir, Turkey ¡ Speaker. ¢c Copyright owned by the author(s) under the terms of the Creative Commons Attribution-NonCommercial-ShareAlike Licence. http://pos.sissa.it/ Hard (State) Problems John A. Tomsick 1. Overview This work is devoted to a discussion of our current understanding of accreting black hole sys- tems when they are in the hard state. In this work, I start by describing the defining properties of the hard state and the questions that we would like to answer concerning the hard state. -
Thomas J. Maccarone Texas Tech
Thomas J. Maccarone PERSONAL Born August 26, 1974, Haverhill, Massachusetts, USA INFORMATION US Citizen CONTACT Department of Physics & Astronomy Voice: +1-806-742-3778 INFORMATION Texas Tech University Lubbock TX 79409 E-mail: [email protected] RESEARCH Compact object populations, especially in globular clusters; accretion and ejection physics; time INTERESTS series analysis methodology PROFESSIONAL Texas Tech University EXPERIENCE Lubbock, Texas Presidential Research Excellence Professor, Department of Physics & Astronomy August 2018-present Professor, Department of Physics & Astronomy August 2017- August 2018 Associate Professor, Department of Physics January 2013 - August 2017 University of Southampton Southampton, UK Lecturer, then Reader, School of Physics and Astronomy July 2005-December 2012 University of Amsterdam Amsterdam, The Netherlands Postdoctoral researcher May 2003 - June 2005 SISSA (Scuola Internazionale di Studi Avanazti/International School for Advanced Studies) Trieste, Italy Postdoctoral researcher November 2001 - April 2003 Yale University New Haven, Connecticut USA Research Assistant May 1997 - August 2001 Jet Propulsion Laboratory Pasadena, California USA Summer Undergraduate Research Fellow June 1994 - August 1994 EDUCATION Yale University, New Haven, CT USA Department of Astronomy Ph.D., December 2001 Dissertation Title: “Constraints on Black Hole Emission Mechanisms” Advisor: Paolo S. Coppi M.S., M.Phil., Astronomy, May 1999 California Institute of Technology, Pasadena, California USA B.S., Physics, June, 1996 HONORS AND Integrated Scholar, Designation from Texas Tech for faculty who integrate teaching, research and AWARDS service activities together, 2020 Professor of the Year Award, Texas Tech Society of Physics Students, 2017, 2019 Dirk Brouwer Prize from Yale University for “a contribution of unusual merit to any branch of astronomy,” 2003 Harry A. -
NL#135 May/June
May/June 2007 Issue 135 A Publication for the members of the American Astronomical Society 3 IOP to Publish President’s Column AAS Journals J. Craig Wheeler, [email protected] Whew! A lot has happened! 5 Member Deaths First, my congratulations to John Huchra who was elected to be the next President of the Society. John will formally become President-Elect at the meeting in Hawaii. He will then take over as President at the meeting in St. Louis in June of 2008 and I will serve as Past-President until the 6 Pasadena meeting in June of 2009. We have hired a consultant to lead a one-day Council retreat before the Hawaii meeting to guide the Council toward a more strategic outlook for the Society. Seattle Meeting John has generously agreed to join that effort. I know he will put his energy, intellect, and experience Highlights behind the health and future of the Society. We had a short, intense, and very professional process to issue a Request for Proposals (RFP) to 10 publish the Astrophysical Journal and the Astronomical Journal, to evaluate the proposals, and Award Winners to select a vendor. We are very pleased that the IOP Publishing will be the new publisher of our cherished and prestigious journals and are very optimistic that our new partnership will lead to in Seattle a necessary and valuable evolution of what it means to publish science journals in the globally- connected electronic age. 11 The complex RFP defining our journals and our aspirations for them was put together by a team International consisting of AAS representatives and outside independent consultants. -
Skytools Chart
29 Scorpius - Ophiuchus SkyTools 3 / Skyhound.com M107 ο ν Box Nebula γ Libra η ξ Eagle Nebula φ θ α2 6356 χ M9 Omega Nebula PK 008+06.1 ν 2 β β1 6342 ψ κ M 23 1 ω 1 6567 2 ι 6440 ω ω Red Spider ξ IC 4634 NGC 6595 6235 5897 6287 M80 δ NGC 6568 μ NGC 6469 6325 ρ M 21 ο Little Ghost Nebula PK 342+27.1 M 20 6401 NGC 6546 6284 Collinder 367 Trifid Nebula θ 6144 M4 σ NGC 6530 M19 Antares π Lagoon Nebula 6293 6544 6355 Collinder 302 σ M28 6553 τ 6316 υ PK 001-00.1 ρ 5694 6540 NGC 6520 PK 357+02.1 6304 Collinder 351 M62 PK 003-04.7 τ PK 002-03.5 Collinder 331 6528 γ1 Tom Thumb Cluster 26522 NGC 6416 δ γ NGC 6425 PK 002-05.1 Collinder 337 6624 NGC 6383 -3 PK 001-06.2 0° Butterfly Cluster χ 6558 Collinder 336 ε 1 5824 6569 PK 356-03.4 2ψ PK 357-04.3 ψ M69 Scorpius PK 358-06.1 M 7 6453 6652 θ ε Collinder 355 NGC 6400 2 λ υ NGC 6281 μ1 5986 φ 6441 PK 353-04.1 Collinder 332 μ2 6139 η PK 355-06.1 η Collinder 338 NGC 6268 NGC 6242 5873 6153 κ Collinder 318 NGC 6124 PK 352-07.1 Collinder 316 Collinder 343 ι1 NGC 6231 γ δ ψ ζ 2 1 NGC 6322 ζ NGC 6192 ω η θ μ κ -40 PK 345-04.1 NGC 6249 Mu Normae Cluster Lupus ° β η 6388 NGC 6259 NGC 6178 δ 6541 6496 NGC 6250 ε ο θ PK 342-04.1 1 52° x 34° 8 5882 h λ 16h30m00.0s -30°00'00" (Skymark) Globular Cl. -
Relativistic Jets in Active Galactic Nuclei and 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. -
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