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A Revised View of the Canis Major Stellar Overdensity with Decam And
MNRAS 501, 1690–1700 (2021) doi:10.1093/mnras/staa2655 Advance Access publication 2020 October 14 A revised view of the Canis Major stellar overdensity with DECam and Gaia: new evidence of a stellar warp of blue stars Downloaded from https://academic.oup.com/mnras/article/501/2/1690/5923573 by Consejo Superior de Investigaciones Cientificas (CSIC) user on 15 March 2021 Julio A. Carballo-Bello ,1‹ David Mart´ınez-Delgado,2 Jesus´ M. Corral-Santana ,3 Emilio J. Alfaro,2 Camila Navarrete,3,4 A. Katherina Vivas 5 and Marcio´ Catelan 4,6 1Instituto de Alta Investigacion,´ Universidad de Tarapaca,´ Casilla 7D, Arica, Chile 2Instituto de Astrof´ısica de Andaluc´ıa, CSIC, E-18080 Granada, Spain 3European Southern Observatory, Alonso de Cordova´ 3107, Casilla 19001, Santiago, Chile 4Millennium Institute of Astrophysics, Santiago, Chile 5Cerro Tololo Inter-American Observatory, NSF’s National Optical-Infrared Astronomy Research Laboratory, Casilla 603, La Serena, Chile 6Instituto de Astrof´ısica, Facultad de F´ısica, Pontificia Universidad Catolica´ de Chile, Av. Vicuna˜ Mackenna 4860, 782-0436 Macul, Santiago, Chile Accepted 2020 August 27. Received 2020 July 16; in original form 2020 February 24 ABSTRACT We present the Dark Energy Camera (DECam) imaging combined with Gaia Data Release 2 (DR2) data to study the Canis Major overdensity. The presence of the so-called Blue Plume stars in a low-pollution area of the colour–magnitude diagram allows us to derive the distance and proper motions of this stellar feature along the line of sight of its hypothetical core. The stellar overdensity extends on a large area of the sky at low Galactic latitudes, below the plane, and in the range 230◦ <<255◦. -
Complex Stellar Populations in Massive Clusters: Trapping Stars of a Dwarf Disc Galaxy in a Newborn Stellar Supercluster
Mon. Not. R. Astron. Soc. 372, 338–342 (2006) doi:10.1111/j.1365-2966.2006.10867.x Complex stellar populations in massive clusters: trapping stars of a dwarf disc galaxy in a newborn stellar supercluster M. Fellhauer,1,3⋆ P. Kroupa2,3⋆ and N. W. Evans1⋆ 1Institute of Astronomy, University of Cambridge, Madingley Road, Cambridge CB3 0HA 2Argelander Institute for Astronomy, University of Bonn, Auf dem Hug¨ el 71, D-53121 Bonn, Germany 3The Rhine Stellar-Dynamical Network Accepted 2006 July 24. Received 2006 July 21; in original form 2006 April 27 ABSTRACT Some of the most-massive globular clusters of our Milky Way, such as, for example, ω Centauri, show a mixture of stellar populations spanning a few Gyr in age and 1.5 dex in metallicities. In contrast, standard formation scenarios predict that globular and open clusters form in one single starburst event of duration 10 Myr and therefore should exhibit only one age and one metallicity in its stars. Here, we investigate the possibility that a massive stellar supercluster may trap older galactic field stars during its formation process that are later detectable in the cluster as an apparent population of stars with a very different age and metallicity. With a set of numerical N-body simulations, we are able to show that, if the mass of the stellar supercluster is high enough and the stellar velocity dispersion in the cluster is comparable to the dispersion of the surrounding disc stars in the host galaxy, then up to about 40 per cent of its initial mass can be additionally gained from trapped disc stars. -
Introduction to Astronomy from Darkness to Blazing Glory
Introduction to Astronomy From Darkness to Blazing Glory Published by JAS Educational Publications Copyright Pending 2010 JAS Educational Publications All rights reserved. Including the right of reproduction in whole or in part in any form. Second Edition Author: Jeffrey Wright Scott Photographs and Diagrams: Credit NASA, Jet Propulsion Laboratory, USGS, NOAA, Aames Research Center JAS Educational Publications 2601 Oakdale Road, H2 P.O. Box 197 Modesto California 95355 1-888-586-6252 Website: http://.Introastro.com Printing by Minuteman Press, Berkley, California ISBN 978-0-9827200-0-4 1 Introduction to Astronomy From Darkness to Blazing Glory The moon Titan is in the forefront with the moon Tethys behind it. These are two of many of Saturn’s moons Credit: Cassini Imaging Team, ISS, JPL, ESA, NASA 2 Introduction to Astronomy Contents in Brief Chapter 1: Astronomy Basics: Pages 1 – 6 Workbook Pages 1 - 2 Chapter 2: Time: Pages 7 - 10 Workbook Pages 3 - 4 Chapter 3: Solar System Overview: Pages 11 - 14 Workbook Pages 5 - 8 Chapter 4: Our Sun: Pages 15 - 20 Workbook Pages 9 - 16 Chapter 5: The Terrestrial Planets: Page 21 - 39 Workbook Pages 17 - 36 Mercury: Pages 22 - 23 Venus: Pages 24 - 25 Earth: Pages 25 - 34 Mars: Pages 34 - 39 Chapter 6: Outer, Dwarf and Exoplanets Pages: 41-54 Workbook Pages 37 - 48 Jupiter: Pages 41 - 42 Saturn: Pages 42 - 44 Uranus: Pages 44 - 45 Neptune: Pages 45 - 46 Dwarf Planets, Plutoids and Exoplanets: Pages 47 -54 3 Chapter 7: The Moons: Pages: 55 - 66 Workbook Pages 49 - 56 Chapter 8: Rocks and Ice: -
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. -
The Large Scale Universe As a Quasi Quantum White Hole
International Astronomy and Astrophysics Research Journal 3(1): 22-42, 2021; Article no.IAARJ.66092 The Large Scale Universe as a Quasi Quantum White Hole U. V. S. Seshavatharam1*, Eugene Terry Tatum2 and S. Lakshminarayana3 1Honorary Faculty, I-SERVE, Survey no-42, Hitech city, Hyderabad-84,Telangana, India. 2760 Campbell Ln. Ste 106 #161, Bowling Green, KY, USA. 3Department of Nuclear Physics, Andhra University, Visakhapatnam-03, AP, India. Authors’ contributions This work was carried out in collaboration among all authors. Author UVSS designed the study, performed the statistical analysis, wrote the protocol, and wrote the first draft of the manuscript. Authors ETT and SL managed the analyses of the study. All authors read and approved the final manuscript. Article Information Editor(s): (1) Dr. David Garrison, University of Houston-Clear Lake, USA. (2) Professor. Hadia Hassan Selim, National Research Institute of Astronomy and Geophysics, Egypt. Reviewers: (1) Abhishek Kumar Singh, Magadh University, India. (2) Mohsen Lutephy, Azad Islamic university (IAU), Iran. (3) Sie Long Kek, Universiti Tun Hussein Onn Malaysia, Malaysia. (4) N.V.Krishna Prasad, GITAM University, India. (5) Maryam Roushan, University of Mazandaran, Iran. Complete Peer review History: http://www.sdiarticle4.com/review-history/66092 Received 17 January 2021 Original Research Article Accepted 23 March 2021 Published 01 April 2021 ABSTRACT We emphasize the point that, standard model of cosmology is basically a model of classical general relativity and it seems inevitable to have a revision with reference to quantum model of cosmology. Utmost important point to be noted is that, ‘Spin’ is a basic property of quantum mechanics and ‘rotation’ is a very common experience. -
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). -
Interpreting the Spitzer/IRAC Colours of 7 Z 9 Galaxies
MNRAS 000,1–11 (2019) Preprint 15 July 2020 Compiled using MNRAS LATEX style file v3.0 Interpreting the Spitzer/IRAC Colours of 76 z 69 Galaxies: Distinguishing Between Line Emission and Starlight Using ALMA G. W. Roberts-Borsani1;2?, R. S. Ellis2 and N. Laporte3;4;2 1Department of Physics and Astronomy, University of California, Los Angeles, 430 Portola Plaza, Los Angeles, CA 90095, USA 2Department of Physics and Astronomy, University College London, Gower Street, London WC1E 6BT, UK 3Kavli Institute for Cosmology, University of Cambridge, Madingley Road, Cambridge CB3 0HA, UK 4Cavendish Laboratory, University of Cambridge, 19 JJ Thomson Avenue, Cambridge CB3 0HE, UK Accepted XXX. Received YYY; in original form ZZZ ABSTRACT Prior to the launch of JWST, Spitzer/IRAC photometry offers the only means of studying the rest-frame optical properties of z >7 galaxies. Many such high redshift galaxies display a red [3.6]−[4.5] micron colour, often referred to as the “IRAC excess”, which has conven- tionally been interpreted as arising from intense [O III]+Hβ emission within the [4.5] micron bandpass. An appealing aspect of this interpretation is similarly intense line emission seen in star-forming galaxies at lower redshift as well as the redshift-dependent behaviour of the IRAC colours beyond z ∼7 modelled as the various nebular lines move through the two band- passes. In this paper we demonstrate that, given the photometric uncertainties, established stel- lar populations with Balmer (4000 Å rest-frame) breaks, such as those inferred at z >9 where line emission does not contaminate the IRAC bands, can equally well explain the redshift- dependent behaviour of the IRAC colours in 7. -
Many New Variable Stars Discovered in the Core of the Globular Cluster NGC 6715 (M 54) with EMCCD Observations DOI: 10.1051/0004-6361/201628864
The University of Manchester Research Many new variable stars discovered in the core of the globular cluster NGC 6715 (M 54) with EMCCD observations DOI: 10.1051/0004-6361/201628864 Document Version Accepted author manuscript Link to publication record in Manchester Research Explorer Citation for published version (APA): Figuera Jaimes, R., Bramich, D. M., Kains, N., Skottfelt, J., Jørgensen, U. G., Horne, K., Dominik, M., Alsubai, K. A., Bozza, V., Burgdorf, M. J., Calchi Novati, S., Ciceri, S., D'Ago, G., Evans, D. F., Galianni, P., Gu, S. H., W Harpsøe, K. B., Haugbølle, T., Hinse, T. C., ... Wertz, O. (2016). Many new variable stars discovered in the core of the globular cluster NGC 6715 (M 54) with EMCCD observations. Astronomy and Astrophysics, 592, [A120]. https://doi.org/10.1051/0004-6361/201628864 Published in: Astronomy and Astrophysics Citing this paper Please note that where the full-text provided on Manchester Research Explorer is the Author Accepted Manuscript or Proof version this may differ from the final Published version. If citing, it is advised that you check and use the publisher's definitive version. General rights Copyright and moral rights for the publications made accessible in the Research Explorer are retained by the authors and/or other copyright owners and it is a condition of accessing publications that users recognise and abide by the legal requirements associated with these rights. Takedown policy If you believe that this document breaches copyright please refer to the University of Manchester’s Takedown Procedures [http://man.ac.uk/04Y6Bo] or contact [email protected] providing relevant details, so we can investigate your claim. -
Blue Straggler Stars in Galactic Open Clusters and the Effect of Field Star Contamination
A&A 482, 777–781 (2008) Astronomy DOI: 10.1051/0004-6361:20078629 & c ESO 2008 Astrophysics Blue straggler stars in Galactic open clusters and the effect of field star contamination (Research Note) G. Carraro1,R.A.Vázquez2, and A. Moitinho3 1 ESO, Alonso de Cordova 3107, Vitacura, Santiago, Chile e-mail: [email protected] 2 Facultad de Ciencias Astronómicas y Geofísicas de la UNLP, IALP-CONICET, Paseo del Bosque s/n, La Plata, Argentina e-mail: [email protected] 3 SIM/IDL, Faculdade de Ciências da Universidade de Lisboa, Ed. C8, Campo Grande, 1749-016 Lisboa, Portugal e-mail: [email protected] Received 7 September 2007 / Accepted 19 February 2008 ABSTRACT Context. We investigate the distribution of blue straggler stars in the field of three open star clusters. Aims. The main purpose is to highlight the crucial role played by general Galactic disk fore-/back-ground field stars, which are often located in the same region of the color magnitude diagram as blue straggler stars. Methods. We analyze photometry taken from the literature of 3 open clusters of intermediate/old age rich in blue straggler stars, which are projected in the direction of the Perseus arm, and study their spatial distribution and the color magnitude diagram. Results. As expected, we find that a large portion of the blue straggler population in these clusters are simply young field stars belonging to the spiral arm. This result has important consequences on the theories of the formation and statistics of blue straggler stars in different population environments: open clusters, globular clusters, or dwarf galaxies. -
ガンマ線バーストと遠方宇宙・元素の起源� 井上 進�(理研) +共同研究者の皆様 Grbs, Blazars
ProbingwithTMT the (more 時代のFirst than) Stars,GRBsGRB a forUVlittleで切り拓く超遠方宇宙� UNravelling Radiation, help from the B my DarkFields, friends Ages Dust… Mission� GeV Fermi ガンマ線バーストと遠方宇宙・元素の起源� 井上 進�(理研) +共同研究者の皆様 GRBs, blazars R. Salvaterra, T. R. Choudhury, A. Ferrara, B. Ciardi, R. Schneider 分子 ALMA (MNRAS in press, arXiv:0906.2495) Y. Inoue, M. Kobayashi, T. Totani, Y. Niinou (in prep.) z~30-6 ダスト ASTRO-H blazar HiZ-G GRB SPICA 再電離 金属 TMT submm R.ALMA Salvaterra,5@5 T.epoch R. Choudhury, of first starA. Ferrara, formation Inoue, (磁場)� Omukai & Ciardi, Benedetta MNRAS, Ciardi Firstsubmitted (MPA)Radiation (astro-ph/0502218) Fields,! FirstB. MagneticCiardi, R. Schneider Fields,lots of First theory Star Formation SKA K. Ichiki, K. KiyotomoTakahashi Ichiki (CfCP/NAOJ) but almost no observations!!! K. Omukai Keitaro Takahashi (Princeton) IceCube SKA CTA CTA “in an interstella burst i am back to reveal the universe” radio see - after T. Yorke also かなた outline� I. GRBs and the high-z Universe - overview: early excitement vs recent calming down - quasar contribution to reionization - gamma-ray probe of UV background *star formation rate, metal evolution, damping wings… -> later talks recent reviews: Space Sci. Rev. (2016) 202� II. neutron star mergers and r-process nucleosynthesis - potential of X-ray diagnostics cosmic dark ages -> cosmic dawn� - big bang� z~3600� - matter-rad. eq.� z~1000� - recombination� dark ages� z>~30� - first stars, galaxies, black holes… -> reionization z~8-10� z~6� - reion. ends - star formation � z~1-3 peak� z~0� adapted -
The Messier Catalog
The Messier Catalog Messier 1 Messier 2 Messier 3 Messier 4 Messier 5 Crab Nebula globular cluster globular cluster globular cluster globular cluster Messier 6 Messier 7 Messier 8 Messier 9 Messier 10 open cluster open cluster Lagoon Nebula globular cluster globular cluster Butterfly Cluster Ptolemy's Cluster Messier 11 Messier 12 Messier 13 Messier 14 Messier 15 Wild Duck Cluster globular cluster Hercules glob luster globular cluster globular cluster Messier 16 Messier 17 Messier 18 Messier 19 Messier 20 Eagle Nebula The Omega, Swan, open cluster globular cluster Trifid Nebula or Horseshoe Nebula Messier 21 Messier 22 Messier 23 Messier 24 Messier 25 open cluster globular cluster open cluster Milky Way Patch open cluster Messier 26 Messier 27 Messier 28 Messier 29 Messier 30 open cluster Dumbbell Nebula globular cluster open cluster globular cluster Messier 31 Messier 32 Messier 33 Messier 34 Messier 35 Andromeda dwarf Andromeda Galaxy Triangulum Galaxy open cluster open cluster elliptical galaxy Messier 36 Messier 37 Messier 38 Messier 39 Messier 40 open cluster open cluster open cluster open cluster double star Winecke 4 Messier 41 Messier 42/43 Messier 44 Messier 45 Messier 46 open cluster Orion Nebula Praesepe Pleiades open cluster Beehive Cluster Suburu Messier 47 Messier 48 Messier 49 Messier 50 Messier 51 open cluster open cluster elliptical galaxy open cluster Whirlpool Galaxy Messier 52 Messier 53 Messier 54 Messier 55 Messier 56 open cluster globular cluster globular cluster globular cluster globular cluster Messier 57 Messier -
The Dwarf Galaxy Abundances and Radial-Velocities Team (DART) Large Programme – a Close Look at Nearby Galaxies
Reports from Observers The Dwarf galaxy Abundances and Radial-velocities Team (DART) Large Programme – A Close Look at Nearby Galaxies Eline Tolstoy1 The dwarf galaxies we have studied are nearby galaxies. The modes of operation, Vanessa Hill 2 the lowest-luminosity (and mass) galax- the sensitivity and the field of view are Mike Irwin ies that have ever been found. It is likely an almost perfect match to requirements Amina Helmi1 that these low-mass dwarfs are the most for the study of Galactic dSph galaxies. Giuseppina Battaglia1 common type of galaxy in the Universe, For example, it is now possible to meas- Bruno Letarte1 but because of their extremely low ure the abundance of numerous elements Kim Venn surface brightness our ability to detect in nearby galaxies for more than 100 stars Pascale Jablonka 5,6 them diminishes rapidly with increasing over a 25;-diameter field of view in one Matthew Shetrone 7 distance. The only place where we can shot. A vast improvement on previous la- Nobuo Arimoto 8 be reasonably sure to detect a large frac- borious (but valiant) efforts with single-slit Tom Abel 9 tion of these objects is in the Local spectrographs to observe a handful of Francesca Primas10 Group, and even here, ‘complete sam- stars per galaxy (e.g., Tolstoy et al. 200; Andreas Kaufer10 ples’ are added to each year. Within Shetrone et al. 200; Geisler et al. 2005). Thomas Szeifert10 250 kpc of our Galaxy there are nine low- Patrick Francois 2 mass galaxies (seven observable from The DART Large Programme has meas- Kozo Sadakane11 the southern hemisphere), including Sag- ured abundances and velocities for sev- ittarius which is in the process of merging eral hundred individual stars in a sample with our Galaxy.