Study of Globular Cluster Sources Using Erass1 Data
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Issue 59, Yir 2015
1 Director’s Message 50 Fast Turnaround Program Markus Kissler-Patig Pilot Underway Rachel Mason 3 Probing Time Delays in a Gravitationally Lensed Quasar 54 Base Facility Operations Keren Sharon Gustavo Arriagada 7 GPI Discovers the Most Jupiter-like 58 GRACES: The Beginning of a Exoplanet Ever Directly Detected Scientific Legacy Julien Rameau and Robert De Rosa André-Nicolas Chené 12 First Likely Planets in a Nearby 62 The New Cloud-based Gemini Circumbinary Disk Observatory Archive Valerie Rapson Paul Hirst 16 RCW 41: Dissecting a Very Young 65 Solar Panel System Installed at Cluster with Adaptive Optics Gemini North Benoit Neichel Alexis-Ann Acohido 21 Science Highlights 67 Gemini Legacy Image Releases Nancy A. Levenson Gemini staff contributions 30 On the Horizon 72 Journey Through the Universe Gemini staff contributions Janice Harvey 37 News for Users 75 Viaje al Universo Gemini staff contributions Maria-Antonieta García 46 Adaptive Optics at Gemini South Gaetano Sivo, Vincent Garrel, Rodrigo Carrasco, Markus Hartung, Eduardo Marin, Vanessa Montes, and Chad Trujillo ON THE COVER: GeminiFocus January 2016 A montage featuring GeminiFocus is a quarterly publication a recent Flamingos-2 of the Gemini Observatory image of the galaxy 670 N. A‘ohoku Place, Hilo, Hawai‘i 96720, USA NGC 253’s inner region Phone: (808) 974-2500 Fax: (808) 974-2589 (as discussed in the Science Highlights Online viewing address: section, page 21; with www.gemini.edu/geminifocus an inset showing the Managing Editor: Peter Michaud stellar supercluster Science Editor: Nancy A. Levenson identified as the galaxy’s nucleus) Associate Editor: Stephen James O’Meara and cover pages Designer: Eve Furchgott/Blue Heron Multimedia from each of issue of Any opinions, findings, and conclusions or GeminiFocus in 2015. -
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. -
A Near-Infrared Photometric Survey of Metal-Poor Inner Spheroid Globular Clusters and Nearby Bulge Fields
View metadata, citation and similar papers at core.ac.uk brought to you by CORE provided by CERN Document Server A Near-Infrared Photometric Survey of Metal-Poor Inner Spheroid Globular Clusters and Nearby Bulge Fields T. J. Davidge 1 Canadian Gemini Office, Herzberg Institute of Astrophysics, National Research Council of Canada, 5071 W. Saanich Road, Victoria, B. C. Canada V8X 4M6 email:[email protected] ABSTRACT Images recorded through J; H; K; 2:2µm continuum, and CO filters have been obtained of a sample of metal-poor ([Fe/H] 1:3) globular clusters ≤− in the inner spheroid of the Galaxy. The shape and color of the upper giant branch on the (K; J K) color-magnitude diagram (CMD), combined with − the K brightness of the giant branch tip, are used to estimate the metallicity, reddening, and distance of each cluster. CO indices are used to identify bulge stars, which will bias metallicity and distance estimates if not culled from the data. The distances and reddenings derived from these data are consistent with published values, although there are exceptions. The reddening-corrected distance modulus of the Galactic Center, based on the Carney et al. (1992, ApJ, 386, 663) HB brightness calibration, is estimated to be 14:9 0:1. The mean ± upper giant branch CO index shows cluster-to-cluster scatter that (1) is larger than expected from the uncertainties in the photometric calibration, and (2) is consistent with a dispersion in CNO abundances comparable to that measured among halo stars. The luminosity functions (LFs) of upper giant branch stars in the program clusters tend to be steeper than those in the halo clusters NGC 288, NGC 362, and NGC 7089. -
On the Possibility of Registering X-Ray Flares Related to Fast Radio
On the possibility of registering X-ray flares related to fast radio bursts with the SRG/eROSITA telescope A.D. Khokhryakova1, D.A. Lyapina1, S.B. Popov1;2;3 1 Department of Physics, Lomonosov Moscow State University 2 Sternberg Astronomical Institute, Lomonosov Moscow State University 3 Higher School of Economics, Moscow March 27, 2019 Abstract In this note we discuss the possibility of detecting the accompanying X-ray emission from sources of fast radio bursts with the eROSITA telescope on- board the Spektr-RG observatory. It is shown that during four years of the survey program about 300 bursts are expected to appear in the field of view of eROSITA. About 1% of them will be detected by ground-based radio tele- scopes. For a total energy release ∼ 1046 ergs depending on the spectral parameters and absorption in the interstellar and intergalactic media, an X- ray flare can be detected from distances from ∼ 1 Mpc (thermal spectrum with kT = 200 keV and strong absorption) up to ∼ 1 Gpc (power-law spec- trum with photon index Γ = 2 and realistic absorption). Thus, eROSITA observations might help to provide important constraints on parameters of arXiv:1903.10991v1 [astro-ph.HE] 26 Mar 2019 sources of fast radio bursts, or may even allow to identify the X-ray tran- sient counterparts, which will help to constrain models of fast radio bursts generation. 1 1 Introduction Fast radio bursts (FRBs) are short (∼ms) bright (peak fluxes up to ∼100 Jy) radio flashes (for a review, see [1]).1 The first event from this class of tran- sients was introduced in 2007 in [2]. -
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. -
Report of Contributions
Mapping the X-ray Sky with SRG: First Results from eROSITA and ART-XC Report of Contributions https://events.mpe.mpg.de/e/SRG2020 Mapping the X- … / Report of Contributions eROSITA discovery of a new AGN … Contribution ID : 4 Type : Oral Presentation eROSITA discovery of a new AGN state in 1H0707-495 Tuesday, 17 March 2020 17:45 (15) One of the most prominent AGNs, the ultrasoft Narrow-Line Seyfert 1 Galaxy 1H0707-495, has been observed with eROSITA as one of the first CAL/PV observations on October 13, 2019 for about 60.000 seconds. 1H 0707-495 is a highly variable AGN, with a complex, steep X-ray spectrum, which has been the subject of intense study with XMM-Newton in the past. 1H0707-495 entered an historical low hard flux state, first detected with eROSITA, never seen before in the 20 years of XMM-Newton observations. In addition ultra-soft emission with a variability factor of about 100 has been detected for the first time in the eROSITA light curves. We discuss fast spectral transitions between the cool and a hot phase of the accretion flow in the very strong GR regime as a physical model for 1H0707-495, and provide tests on previously discussed models. Presenter status Senior eROSITA consortium member Primary author(s) : Prof. BOLLER, Thomas (MPE); Prof. NANDRA, Kirpal (MPE Garching); Dr LIU, Teng (MPE Garching); MERLONI, Andrea; Dr DAUSER, Thomas (FAU Nürnberg); Dr RAU, Arne (MPE Garching); Dr BUCHNER, Johannes (MPE); Dr FREYBERG, Michael (MPE) Presenter(s) : Prof. BOLLER, Thomas (MPE) Session Classification : AGN physics, variability, clustering October 3, 2021 Page 1 Mapping the X- … / Report of Contributions X-ray emission from warm-hot int … Contribution ID : 9 Type : Poster X-ray emission from warm-hot intergalactic medium: the role of resonantly scattered cosmic X-ray background We revisit calculations of the X-ray emission from warm-hot intergalactic medium (WHIM) with particular focus on contribution from the resonantly scattered cosmic X-ray background (CXB). -
Erosita – Mapping the X-Ray Universe by P. Predehl
Astron. Nachr. /AN 335, No. 5, 517 – 522 (2014) / DOI 10.1002/asna.201412059 eROSITA – Mapping the X-ray universe P. Predehl Max-Planck-Institut f¨ur extraterrestrische Physik, Giessenbachstraße, D-85748 Garching, Germany Received 2014 Apr 7, accepted 2014 Apr 10 Published online 2014 Jun 2 Key words space vehicles – surveys – telescopes – X-rays: general eROSITA (extended ROentgen Survey with an Imaging Telescope Array) is the core instrument on the Russian/German Spektrum-Roentgen-Gamma (SRG) mission which is currently scheduled for launch late 2015/early 2016. eROSITA will perform a deep survey of the entire X-ray sky. In the soft band (0.5–2 keV), it will be about 30 times more sensitive than ROSAT, while in the hard band (2–8 keV) it will provide the first ever true imaging survey of the sky. The design driving science is the detection of large samples of galaxy clusters to redshifts z>1 in order to study the large scale structure in the universe and test cosmological models including dark energy. In addition, eROSITA is expected to yield a sample of a few million active galactic nuclei, including obscured objects, revolutionizing our view of the evolution of supermassive black holes. The survey will also provide new insights into a wide range of astrophysical phenomena, including X-ray binaries, active stars, and diffuse emission within the Galaxy. eROSITA is currently (Jan 2014) in its flight model and calibration phase. All seven flight mirror modules (plus one spare) have been delivered and measured in X-rays. The first camera including the complete electronics has been extensively tested. -
Publications of the Astronomical Society of the Pacific 106: 404-412, 1994 April
Publications of the Astronomical Society of the Pacific 106: 404-412, 1994 April CCD Photometry of the Galactic Globular Cluster NGC 6535 in the Β and Passbands Ata Sarajedini1 Kitt Peak National Observatory, National Optical Astronomy Observatories,2 P.O. Box 26732, Tucson, Arizona 85726-6732 Electronic mail: [email protected] Received 1993 October 15; accepted 1994 February 1 ABSTRACT. The first CCD color-magnitude diagram (CMD) in Β and V is presented for the Galactic globular cluster NGC 6535. From this CMD, which extends below the main-sequence turnoff, we draw the following conclusions: (1) The horizontal branch (HB) is predominantly blue in nature with no RR Lyrae variables known to be cluster members. Nonetheless, based on a comparison with clusters which have blue HBs and RR Lyraes (Ml5 and M79), we infer a mean HB magnitude of <^RR> = 15.73 ±0.11 for NGC 6535. (2) Again, via a direct comparison with the blue HBs of M15 and M79, we derive a cluster reddening oíE{B—V) =0.44±0.02. (3) When combined with the apparent color of the red-giant branch at the level of the HB, (B—V)g= 1.18 ±0.02, the derived reddening yields a metal abundance of [Fe/H] = —1.85 ±0.10, similar to that of NGC 6397. (4) Application of the AFT0_hb and Δ(5— F)SGB_To cluster dating techniques reveals no perceptible age difference between NGC 6535 and NGC 6397. (5) A significant population of nine blue-straggler candidates is detected in NGC 6535. However, this is too few to facilitate a meaningful analysis of their radial distribution. -
A Basic Requirement for Studying the Heavens Is Determining Where In
Abasic requirement for studying the heavens is determining where in the sky things are. To specify sky positions, astronomers have developed several coordinate systems. Each uses a coordinate grid projected on to the celestial sphere, in analogy to the geographic coordinate system used on the surface of the Earth. The coordinate systems differ only in their choice of the fundamental plane, which divides the sky into two equal hemispheres along a great circle (the fundamental plane of the geographic system is the Earth's equator) . Each coordinate system is named for its choice of fundamental plane. The equatorial coordinate system is probably the most widely used celestial coordinate system. It is also the one most closely related to the geographic coordinate system, because they use the same fun damental plane and the same poles. The projection of the Earth's equator onto the celestial sphere is called the celestial equator. Similarly, projecting the geographic poles on to the celest ial sphere defines the north and south celestial poles. However, there is an important difference between the equatorial and geographic coordinate systems: the geographic system is fixed to the Earth; it rotates as the Earth does . The equatorial system is fixed to the stars, so it appears to rotate across the sky with the stars, but of course it's really the Earth rotating under the fixed sky. The latitudinal (latitude-like) angle of the equatorial system is called declination (Dec for short) . It measures the angle of an object above or below the celestial equator. The longitud inal angle is called the right ascension (RA for short). -
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. -
Arxiv:2012.05245V2 [Astro-Ph.GA] 5 May 2021
Draft version May 6, 2021 Typeset using LATEX twocolumn style in AASTeX63 Charting the Galactic acceleration field I. A search for stellar streams with Gaia DR2 and EDR3 with follow-up from ESPaDOnS and UVES Rodrigo Ibata 1 | Khyati Malhan 2 | Nicolas Martin 1, 3 | Dominique Aubert1 | Benoit Famaey 1 | Paolo Bianchini 1 | Giacomo Monari 1 | Arnaud Siebert 1 | Guillaume F. Thomas 4, 5 | Michele Bellazzini 6 | Piercarlo Bonifacio7 | Elisabetta Caffau7 | Florent Renaud 8 | arXiv:2012.05245v2 [astro-ph.GA] 5 May 2021 1Universit´ede Strasbourg, CNRS, Observatoire astronomique de Strasbourg, UMR 7550, F-67000 Strasbourg, France 2The Oskar Klein Centre, Department of Physics, Stockholm University, AlbaNova, SE-10691 Stockholm, Sweden 3Max-Planck-Institut f¨urAstronomie, K¨onigstuhl17, D-69117, Heidelberg, Germany 4Instituto de Astrof´ısica de Canarias, E-38205 La Laguna, Tenerife, Spain 5Universidad de La Laguna, Dpto. Astrof´ısica, E-38206 La Laguna, Tenerife, Spain 6INAF - Osservatorio di Astrofisica e Scienza dello Spazio, via Gobetti 93/3, I-40129 Bologna, Italy 7GEPI, Observatoire de Paris, Universit´ePSL, CNRS, 5 Place Jules Janssen, 92190 Meudon, France 8Department of Astronomy and Theoretical Physics, Lund Observatory, Box 43, 221 00 Lund, Sweden Corresponding author: Rodrigo Ibata [email protected] 2 Ibata et al. Submitted to ApJ ABSTRACT We present maps of the stellar streams detected in the Gaia Data Release 2 (DR2) and Early Data Release 3 (EDR3) catalogs using the STREAMFINDER algorithm. We also report the spectroscopic follow-up of the brighter DR2 stream members obtained with the high-resolution CFHT/ESPaDOnS and VLT/UVES spectrographs as well as with the medium-resolution NTT/EFOSC2 spectrograph. -
Atlas Menor Was Objects to Slowly Change Over Time
C h a r t Atlas Charts s O b by j Objects e c t Constellation s Objects by Number 64 Objects by Type 71 Objects by Name 76 Messier Objects 78 Caldwell Objects 81 Orion & Stars by Name 84 Lepus, circa , Brightest Stars 86 1720 , Closest Stars 87 Mythology 88 Bimonthly Sky Charts 92 Meteor Showers 105 Sun, Moon and Planets 106 Observing Considerations 113 Expanded Glossary 115 Th e 88 Constellations, plus 126 Chart Reference BACK PAGE Introduction he night sky was charted by western civilization a few thou - N 1,370 deep sky objects and 360 double stars (two stars—one sands years ago to bring order to the random splatter of stars, often orbits the other) plotted with observing information for T and in the hopes, as a piece of the puzzle, to help “understand” every object. the forces of nature. The stars and their constellations were imbued with N Inclusion of many “famous” celestial objects, even though the beliefs of those times, which have become mythology. they are beyond the reach of a 6 to 8-inch diameter telescope. The oldest known celestial atlas is in the book, Almagest , by N Expanded glossary to define and/or explain terms and Claudius Ptolemy, a Greco-Egyptian with Roman citizenship who lived concepts. in Alexandria from 90 to 160 AD. The Almagest is the earliest surviving astronomical treatise—a 600-page tome. The star charts are in tabular N Black stars on a white background, a preferred format for star form, by constellation, and the locations of the stars are described by charts.