DOCSLIB.ORG

Regulation of Star Formation Amidst Heating and Cooling in Galaxies and Galaxy Clusters

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text

Load more

Rochester Institute of Technology RIT Scholar Works Theses 8-2016 Regulation of Star Formation Amidst Heating and Cooling in Galaxies and Galaxy Clusters Sravani Vaddi [email protected] Follow this and additional works at: https://scholarworks.rit.edu/theses Recommended Citation Vaddi, Sravani, "Regulation of Star Formation Amidst Heating and Cooling in Galaxies and Galaxy Clusters" (2016). Thesis. Rochester Institute of Technology. Accessed from This Dissertation is brought to you for free and open access by RIT Scholar Works. It has been accepted for inclusion in Theses by an authorized administrator of RIT Scholar Works. For more information, please contact [email protected]. Regulation of Star Formation amidst Heating and Cooling in Galaxies and Galaxy Clusters by Sravani Vaddi A dissertation submitted in partial fulfillment of the requirements for the degree of Ph.D. in Astrophysical Sciences and Technology in the College of Science, School of Physics and Astronomy Rochester Institute of Technology August, 2016 Approved by Dr. Andrew Robinson Date Director, Astrophysical Sciences and Technology Astrophysical Sciences and Technology College of Science Rochester Institute of Technology Rochester, New York, USA Certificate of Approval Ph.D. Degree Dissertation The Ph.D. Degree Dissertation of SRAVANI VADDI has been examined and approved by the dissertation committee as satisfactory for the dissertation requirement for the Ph.D. degree in Astrophysical Sciences and Technology. Dr. Chris O’Dea, Dissertation Advisor Date Dr. Stefi Baum, Dissertation Advisor Date Dr. Anthony Vodacek, Committee Chair Date Dr. Alice Quillen Date Dr. Andrew Robinson Date To all my teachers who believed in me and supported me all through my life. ABSTRACT Galaxy clusters are the largest gravitationally bound systems in the Uni- verse and often host the largest galaxies (known as the brightest cluster galaxies (BCG)) at its centers. These BCG’s are embedded in hot 1-10 keV X-ray gas. A subset of galaxy clusters known as cool-core clusters show sharply peaked X-ray emission and high central densities, demonstrating cooling of the surrounding halo gas in timescales much shorter than a Hub- ble time. These observations led to the development of a simple cooling flow model. In the absence of an external heating process, a cooling flow model predicts that the hot intracluster medium gas in these dense cores would hydrostatically cool, generating cooling flows in the center of the cluster. This cooled gas will eventually collapse to form stars and contribute to the bulk of galaxy mass. The rates of star formation actually observed in the clusters however are far less than predicted by the cooling flow model, sug- gesting a non-gravitational heating source. Active galactic nuclei (AGN), galaxies hosting a supermassive black hole that ejects outflows via accretion, is currently the leading heating mechanism (referred to as AGN feedback) explaining the observed deficit in the star formation rates. AGN feedback also offers an elegant explanation to the observed black hole and galaxy co- evolution. Much of the evidence for AGN feedback has been obtained from studies focussed on galaxy clusters and luminous massive systems with little evidence that it occurs in more typical systems in the local universe. Our re- search investigates this less explored area to address the importance of AGN heating in the regulation of star formation in typical early type galaxies in the local universe. We selected a sample of 200+ early type, low redshift galaxies and carried out a multiple wavelength study using archival observed in the UV, IR and radio. Our results suggest that early type galaxies in the i current epoch are rarely powerful AGN and AGN feedback is constrained to be low in our sample of low redshift, typical early type galaxies. Although heating from the AGN is powerful enough to suppress the cool- ing of the hot gas, it does not completely offset gas cooling at all times and substantial cooler gas exists in the cores of some galaxy clusters (cool-core clusters), the gas properties of which are not explained by AGN heating models alone. The second part of our research focusses on unravelling the mystery of the unknown heating source regulating star formation in galaxy clusters. We have obtained deep FUV spectroscopy using the HST cos- mic origins spectrograph of two cool-core clusters A2597 and Zw3146. FUV spectral lines provide the much needed diagnostics capable of discriminating between various heating models, which was difficult with the standard op- tical line diagnostics. We investigate several heating/ionization mechanisms namely stellar photoionization, AGN photoionization, and shock heating. We use pre-run Mappings III photoionization code results to model the ion- izing radiation field. In general, we notice that there is no one single model that provides a satisfactory explanation for the ionization state of gas. How- ever, we show that stellar and AGN photoionization alone are not enough to ionize the nebula in A2597 and speculate that, shock heating is the likely ionizing source. ii ACKNOWLEDGEMENTS My journey would not have been made possible without help from my family, teachers, and friends. This is the journey of an engineer who dreamt of becoming an astronomer. As I am writing this, I look back to remember all the people who have helped me in making this dream come to true. I am immensely thankful to my advisors Dr. Chris O’Dea and Dr. Stefi Baum for their unending support and encouragement during these years. Even after moving to Manitoba, Dr. O’dea had provided me continual guidance and was readily available to answer questions. I am also grateful to my profes- sors Dr. Andrew Robinson, Dr. Michael Richmond, Dr. David Merritt, Dr. Joel Kastner from whom I have learnt so many things. A special mention to Dr. Michael Richmond for giving me hands-on experience with telescopes and also for providing outreach opportunities at the observatory. I thank Dr. Christine Jones and Dr. Bill Forman for constructing and sharing the galaxy sample with me which formed the basis for this project. This journey would not have been possible without my dear mentors Dr. Najam Hasan and Dr. Priya Hasan who welcomed my dream of becoming an astronomer and gave me an opportunity to work with them. I wish to thank my inspirational teachers Mr. Phani Bhushan and late Mr. Timma Reddy who believed in me and motivated me to reach for the stars. I thank my wonderful friends for making this a fun-filled and most mem- orable journey. The hikes we went to, and movie nights, festivals and dinners we enjoyed have enriched my life. I thank you for listening to me and the advice you all provided. Among them are Adnan Kashif, Davide Lena, Dave Principe, Preeti Vaidyanathan, Ashima Chhabra, Alexander Rasskavoz, Di- iii nalva Sales, Gabor Kupi, Marcus Freeman, Dmitry Vorobiev, Billy Vazquez, Prabath Peiris, Eugene Vasiliev, Christine Trombley, Vg Prasuna, yuanhao Zang, Yashar Seyed, Masoud Golshadi, Mustafa Koz, Kamal Jnawali, Jam Sadiq, Ekta Shah, Triana Almyeda, and Bipana Jnawali. Special thanks to my mentor Preeti Kharb for giving me training on AIPS, and for helping me view issues from different perspectives; Rupal Mittal and Grant Tremblay for insightful discussions on the project. I am deeply appreciative of Cari Hind- man, Cindy Drake, Sue Chan, Joyce French, and Dr. Michael Kotlarchyk, who have been working tirelessly behind the scenes helping the students. I can never thank my family enough for being my strength and respecting my pursuit of Astronomy. In particular, I thank my mother for giving me everything in life. Like a candle, you burnt yourself for lighting up my life. Thank you for all the sacrifices you have made. iv CONTENTS Abstracti Acknowledgements iii List of Tables ix List of Figures xxiii 1 Introduction1 1.1 Galaxy Formation and AGN Feedback.............2 1.1.1 Galaxy Luminosity Function..............4 1.1.2 Co-evolution of galaxy and black hole.........5 1.1.3 ICM heating in cool core galaxy clusters........8 1.1.4 AGN Feedback...................... 10 1.1.5 Quasar Mode....................... 11 1.1.6 Radio-Mode........................ 13 1.2 Galaxy Clusters.......................... 14 1.3 X-ray hot ICM.......................... 16 1.3.1 Physics of the X-ray hot ICM.............. 16 1.3.2 Physical properties of the ICM............. 17 1.4 Cooling Flow Model....................... 20 1.4.1 Problems with the Cooling Flow Model........ 23 1.4.2 Solutions to the CF Model................ 24 1.4.3 Residual Cooling..................... 27 v CONTENTS 1.5 Cool-core BCG Emission Line Nebulae............. 27 1.5.1 Properties of emission line nebulae........... 28 1.6 A review of previous studies................... 31 1.6.1 AGN feedback...................... 31 1.6.2 Ionization of emission line nebulae........... 32 1.7 Goals of the Thesis........................ 33 1.8 Road Map............................. 35 2 Sample and Data Analysis 37 2.1 Sample............................... 37 2.2 The Data............................. 38 2.2.1 IR data.......................... 39 2.2.2 Radio data........................ 40 2.2.3 UV data.......................... 41 2.2.4 Galactic Extinction Correction............. 42 2.3 Aperture Photometry...................... 42 2.4 Photometry comparisions.................... 45 2.4.1 Comparision with the 2MASS.............. 45 2.4.2 Comparison with WISE................. 45 2.4.3 Error Analysis...................... 51 3 Photometric Properties of the Sample 57 3.1 MIR-FUV Properties....................... 57 3.1.1 SFR estimation using FUV............... 61 3.1.2 Galaxy mass estimation................. 64 3.1.3 Specific SFR estimation................. 65 3.2 Radio properties......................... 68 3.3 Summary............................. 69 4 Results and Discussion 72 4.1 Relation between radio power and host galaxy properties... 72 4.1.1 Radio power and galaxy mass relation - Radio power from AGN is dependent on the galaxy mass.....
Recommended publications
  • Cinemática Estelar, Modelos Dinâmicos E Determinaç˜Ao De

    Cinemática Estelar, Modelos Dinâmicos E Determinaç˜Ao De

    UNIVERSIDADE FEDERAL DO RIO GRANDE DO SUL PROGRAMA DE POS´ GRADUA¸CAO~ EM F´ISICA Cinem´atica Estelar, Modelos Din^amicos e Determina¸c~ao de Massas de Buracos Negros Supermassivos Daniel Alf Drehmer Tese realizada sob orienta¸c~aoda Professora Dra. Thaisa Storchi Bergmann e apresen- tada ao Programa de P´os-Gradua¸c~aoem F´ısica do Instituto de F´ısica da UFRGS em preenchimento parcial dos requisitos para a obten¸c~aodo t´ıtulo de Doutor em Ci^encias. Porto Alegre Mar¸co, 2015 Agradecimentos Gostaria de agradecer a todas as pessoas que de alguma forma contribu´ıram para a realiza¸c~ao deste trabalho e em especial agrade¸co: • A` Profa. Dra. Thaisa Storchi-Bergmann pela competente orienta¸c~ao. • Aos professores Dr. Fabr´ıcio Ferrari da Universidade Federal do Rio Grande, Dr. Rogemar Riffel da Universidade Federal de Santa Maria e ao Dr. Michele Cappellari da Universidade de Oxford cujas colabora¸c~oes foram fundamentais para a realiza¸c~ao deste trabalho. • A todos os professores do Departamento de Astronomia do Instituto de F´ısica da Universidade Federal do Rio Grande do Sul que contribu´ıram para minha forma¸c~ao. • Ao CNPq pelo financiamento desse trabalho. • Aos meus pais Ingon e Selia e meus irm~aos Neimar e Carla pelo apoio. Daniel Alf Drehmer Universidade Federal do Rio Grande do Sul Mar¸co2015 i Resumo O foco deste trabalho ´eestudar a influ^encia de buracos negros supermassivos (BNSs) nucleares na din^amica e na cinem´atica estelar da regi~ao central das gal´axias e determinar a massa destes BNSs.
  • An Outline of Stellar Astrophysics with Problems and Solutions

    An Outline of Stellar Astrophysics with Problems and Solutions

    An Outline of Stellar Astrophysics with Problems and Solutions Using Maple R and Mathematica R Robert Roseberry 2016 1 Contents 1 Introduction 5 2 Electromagnetic Radiation 7 2.1 Specific intensity, luminosity and flux density ............7 Problem 1: luminous flux (**) . .8 Problem 2: galaxy fluxes (*) . .8 Problem 3: radiative pressure (**) . .9 2.2 Magnitude ...................................9 Problem 4: magnitude (**) . 10 2.3 Colour ..................................... 11 Problem 5: Planck{Stefan-Boltzmann{Wien{colour (***) . 13 Problem 6: Planck graph (**) . 13 Problem 7: radio and visual luminosity and brightness (***) . 14 Problem 8: Sirius (*) . 15 2.4 Emission Mechanisms: Continuum Emission ............. 15 Problem 9: Orion (***) . 17 Problem 10: synchrotron (***) . 18 Problem 11: Crab (**) . 18 2.5 Emission Mechanisms: Line Emission ................. 19 Problem 12: line spectrum (*) . 20 2.6 Interference: Line Broadening, Scattering, and Zeeman splitting 21 Problem 13: natural broadening (**) . 21 Problem 14: Doppler broadening (*) . 22 Problem 15: Thomson Cross Section (**) . 23 Problem 16: Inverse Compton scattering (***) . 24 Problem 17: normal Zeeman splitting (**) . 25 3 Measuring Distance 26 3.1 Parallax .................................... 27 Problem 18: parallax (*) . 27 3.2 Doppler shifting ............................... 27 Problem 19: supernova distance (***) . 28 3.3 Spectroscopic parallax and Main Sequence fitting .......... 28 Problem 20: Main Sequence fitting (**) . 29 3.4 Standard candles ............................... 30 Video: supernova light curve . 30 Problem 21: Cepheid distance (*) . 30 3.5 Tully-Fisher relation ............................ 31 3.6 Lyman-break galaxies and the Hubble flow .............. 33 4 Transparent Gas: Interstellar Gas Clouds and the Atmospheres and Photospheres of Stars 35 2 4.1 Transfer equation and optical depth .................. 36 Problem 22: optical depth (**) . 37 4.2 Plane-parallel atmosphere, Eddington's approximation, and limb darkening ..................................
  • Virgo the Virgin

    Virgo the Virgin

    Virgo the Virgin Virgo is one of the constellations of the zodiac, the group tion Virgo itself. There is also the connection here with of 12 constellations that lies on the ecliptic plane defined “The Scales of Justice” and the sign Libra which lies next by the planets orbital orientation around the Sun. Virgo is to Virgo in the Zodiac. The study of astronomy had a one of the original 48 constellations charted by Ptolemy. practical “time keeping” aspect in the cultures of ancient It is the largest constellation of the Zodiac and the sec- history and as the stars of Virgo appeared before sunrise ond - largest constellation after Hydra. Virgo is bordered by late in the northern summer, many cultures linked this the constellations of Bootes, Coma Berenices, Leo, Crater, asterism with crops, harvest and fecundity. Corvus, Hydra, Libra and Serpens Caput. The constella- tion of Virgo is highly populated with galaxies and there Virgo is usually depicted with angel - like wings, with an are several galaxy clusters located within its boundaries, ear of wheat in her left hand, marked by the bright star each of which is home to hundreds or even thousands of Spica, which is Latin for “ear of grain”, and a tall blade of galaxies. The accepted abbreviation when enumerating grass, or a palm frond, in her right hand. Spica will be objects within the constellation is Vir, the genitive form is important for us in navigating Virgo in the modern night Virginis and meteor showers that appear to originate from sky. Spica was most likely the star that helped the Greek Virgo are called Virginids.
  • X-Ray Luminosities for a Magnitude-Limited Sample of Early-Type Galaxies from the ROSAT All-Sky Survey

    X-Ray Luminosities for a Magnitude-Limited Sample of Early-Type Galaxies from the ROSAT All-Sky Survey

    Mon. Not. R. Astron. Soc. 302, 209±221 (1999) X-ray luminosities for a magnitude-limited sample of early-type galaxies from the ROSAT All-Sky Survey J. Beuing,1* S. DoÈbereiner,2 H. BoÈhringer2 and R. Bender1 1UniversitaÈts-Sternwarte MuÈnchen, Scheinerstrasse 1, D-81679 MuÈnchen, Germany 2Max-Planck-Institut fuÈr Extraterrestrische Physik, D-85740 Garching bei MuÈnchen, Germany Accepted 1998 August 3. Received 1998 June 1; in original form 1997 December 30 Downloaded from https://academic.oup.com/mnras/article/302/2/209/968033 by guest on 30 September 2021 ABSTRACT For a magnitude-limited optical sample (BT # 13:5 mag) of early-type galaxies, we have derived X-ray luminosities from the ROSATAll-Sky Survey. The results are 101 detections and 192 useful upper limits in the range from 1036 to 1044 erg s1. For most of the galaxies no X-ray data have been available until now. On the basis of this sample with its full sky coverage, we ®nd no galaxy with an unusually low ¯ux from discrete emitters. Below log LB < 9:2L( the X-ray emission is compatible with being entirely due to discrete sources. Above log LB < 11:2L( no galaxy with only discrete emission is found. We further con®rm earlier ®ndings that Lx is strongly correlated with LB. Over the entire data range the slope is found to be 2:23 60:12. We also ®nd a luminosity dependence of this correlation. Below 1 log Lx 40:5 erg s it is consistent with a slope of 1, as expected from discrete emission.
  • 7.5 X 11.5.Threelines.P65

    7.5 X 11.5.Threelines.P65

    Cambridge University Press 978-0-521-19267-5 - Observing and Cataloguing Nebulae and Star Clusters: From Herschel to Dreyer’s New General Catalogue Wolfgang Steinicke Index More information Name index The dates of birth and death, if available, for all 545 people (astronomers, telescope makers etc.) listed here are given. The data are mainly taken from the standard work Biographischer Index der Astronomie (Dick, Brüggenthies 2005). Some information has been added by the author (this especially concerns living twentieth-century astronomers). Members of the families of Dreyer, Lord Rosse and other astronomers (as mentioned in the text) are not listed. For obituaries see the references; compare also the compilations presented by Newcomb–Engelmann (Kempf 1911), Mädler (1873), Bode (1813) and Rudolf Wolf (1890). Markings: bold = portrait; underline = short biography. Abbe, Cleveland (1838–1916), 222–23, As-Sufi, Abd-al-Rahman (903–986), 164, 183, 229, 256, 271, 295, 338–42, 466 15–16, 167, 441–42, 446, 449–50, 455, 344, 346, 348, 360, 364, 367, 369, 393, Abell, George Ogden (1927–1983), 47, 475, 516 395, 395, 396–404, 406, 410, 415, 248 Austin, Edward P. (1843–1906), 6, 82, 423–24, 436, 441, 446, 448, 450, 455, Abbott, Francis Preserved (1799–1883), 335, 337, 446, 450 458–59, 461–63, 470, 477, 481, 483, 517–19 Auwers, Georg Friedrich Julius Arthur v. 505–11, 513–14, 517, 520, 526, 533, Abney, William (1843–1920), 360 (1838–1915), 7, 10, 12, 14–15, 26–27, 540–42, 548–61 Adams, John Couch (1819–1892), 122, 47, 50–51, 61, 65, 68–69, 88, 92–93,
  • Kinematical Data on Early-Type Galaxies. VI.?,??

    Kinematical Data on Early-Type Galaxies. VI.?,??

    A&A 384, 371–382 (2002) Astronomy DOI: 10.1051/0004-6361:20020071 & c ESO 2002 Astrophysics Kinematical data on early-type galaxies. VI.?,?? F. Simien and Ph. Prugniel CRAL-Observatoire de Lyon, CNRS: UMR 142, 69561 St-Genis-Laval Cedex, France Received 8 June 2001 / Accepted 7 December 2001 Abstract. We present the result of spectroscopic observations of a sample of 73 galaxies, completing the database published in this series of articles. The sample contains mostly low-luminosity early-type objects, including four dwarfs of the Local Group (in particular, deep spectra of NGC 205), 15 dEs or dS0s in the Virgo cluster, and UGC 05442, a spheroidal dwarf of the M 81 group. We have measured the central velocity dispersion for all but one object, and determined the major-axis rotation and velocity-dispersion profiles for 59 objects. For the current sample of diffuse (or dwarf) elliptical galaxies, we have compared stellar rotation to velocity dispersion; the analysis suggests that these objects may be nearly rotationally flattened, and therefore that anisotropy may be less important than previously thought. Key words. galaxies: elliptical and lenticular, cD – galaxies: kinematics and dynamics – galaxies: fundamental parameters – galaxies: general 1. Introduction the residuals, and they are correlated with the density of the environment (Prugniel et al. 1999). We have presented kinematical measurements from ab- In the general framework of galaxy formation and evo- sorption spectroscopy on early-type galaxies (Simien lution, the transition between the properties of elliptical & Prugniel 1997a, 1997b, 1997c, 1998, 2000: hereafter galaxies and those of diffuse, or dwarf, ellipticals (dEs), Papers I to V, respectively); these data are intended to is pivotal.
  • The GALEX Ultraviolet Virgo Cluster Survey (Guvics) VII

    The GALEX Ultraviolet Virgo Cluster Survey (Guvics) VII

    A&A 611, A42 (2018) https://doi.org/10.1051/0004-6361/201731795 Astronomy & © ESO 2018 Astrophysics The GALEX Ultraviolet Virgo Cluster Survey (GUViCS) VII. Brightest cluster galaxy UV upturn and the FUV-NUV color up to redshift 0.35? S. Boissier1, O. Cucciati2, A. Boselli1, S. Mei3,4,5, and L. Ferrarese6 1 Aix Marseille Univ, CNRS, LAM, Laboratoire d’Astrophysique de Marseille, Marseille, France e-mail: [email protected] 2 INAF – Osservatorio Astronomico di Bologna, via Gobetti 93/3, 40129 Bologna, Italy 3 LERMA, Observatoire de Paris, PSL Research University, CNRS, Sorbonne Universités, UPMC Univ. Paris 06, 75014 Paris, France 4 Université Paris Denis Diderot, Université Paris Sorbonne Cité, 75205 Paris Cedex 13, France 5 Jet Propulsion Laboratory, California Institute of Technology, Cahill Center for Astronomy & Astrophysics, Pasadena, CA, USA 6 National Research Council of Canada, Herzberg Astronomy and Astrophysics Program, 5071 West Saanich Road, Victoria, BC V9E 2E7, Canada Received 18 August 2017 / Accepted 23 December 2017 ABSTRACT Context. At low redshift, early-type galaxies often exhibit a rising flux with decreasing wavelength in the 1000–2500 Å range, called “UV upturn”. The origin of this phenomenon is debated, and its evolution with redshift is poorly constrained. The observed GALEX FUV-NUV color can be used to probe the UV upturn approximately to redshift 0.5. Aims. We provide constraints on the existence of the UV upturn up to redshift ∼0.4 in the brightest cluster galaxies (BCG) located behind the Virgo cluster, using data from the GUViCS survey. Methods. We estimate the GALEX far-UV (FUV) and near-UV (NUV) observed magnitudes for BCGs from the maxBCG catalog in the GUViCS fields.
  • Making a Sky Atlas

    Making a Sky Atlas

    Appendix A Making a Sky Atlas Although a number of very advanced sky atlases are now available in print, none is likely to be ideal for any given task. Published atlases will probably have too few or too many guide stars, too few or too many deep-sky objects plotted in them, wrong- size charts, etc. I found that with MegaStar I could design and make, specifically for my survey, a “just right” personalized atlas. My atlas consists of 108 charts, each about twenty square degrees in size, with guide stars down to magnitude 8.9. I used only the northernmost 78 charts, since I observed the sky only down to –35°. On the charts I plotted only the objects I wanted to observe. In addition I made enlargements of small, overcrowded areas (“quad charts”) as well as separate large-scale charts for the Virgo Galaxy Cluster, the latter with guide stars down to magnitude 11.4. I put the charts in plastic sheet protectors in a three-ring binder, taking them out and plac- ing them on my telescope mount’s clipboard as needed. To find an object I would use the 35 mm finder (except in the Virgo Cluster, where I used the 60 mm as the finder) to point the ensemble of telescopes at the indicated spot among the guide stars. If the object was not seen in the 35 mm, as it usually was not, I would then look in the larger telescopes. If the object was not immediately visible even in the primary telescope – a not uncommon occur- rence due to inexact initial pointing – I would then scan around for it.
  • Ngc Catalogue Ngc Catalogue

    Ngc Catalogue Ngc Catalogue

    NGC CATALOGUE NGC CATALOGUE 1 NGC CATALOGUE Object # Common Name Type Constellation Magnitude RA Dec NGC 1 - Galaxy Pegasus 12.9 00:07:16 27:42:32 NGC 2 - Galaxy Pegasus 14.2 00:07:17 27:40:43 NGC 3 - Galaxy Pisces 13.3 00:07:17 08:18:05 NGC 4 - Galaxy Pisces 15.8 00:07:24 08:22:26 NGC 5 - Galaxy Andromeda 13.3 00:07:49 35:21:46 NGC 6 NGC 20 Galaxy Andromeda 13.1 00:09:33 33:18:32 NGC 7 - Galaxy Sculptor 13.9 00:08:21 -29:54:59 NGC 8 - Double Star Pegasus - 00:08:45 23:50:19 NGC 9 - Galaxy Pegasus 13.5 00:08:54 23:49:04 NGC 10 - Galaxy Sculptor 12.5 00:08:34 -33:51:28 NGC 11 - Galaxy Andromeda 13.7 00:08:42 37:26:53 NGC 12 - Galaxy Pisces 13.1 00:08:45 04:36:44 NGC 13 - Galaxy Andromeda 13.2 00:08:48 33:25:59 NGC 14 - Galaxy Pegasus 12.1 00:08:46 15:48:57 NGC 15 - Galaxy Pegasus 13.8 00:09:02 21:37:30 NGC 16 - Galaxy Pegasus 12.0 00:09:04 27:43:48 NGC 17 NGC 34 Galaxy Cetus 14.4 00:11:07 -12:06:28 NGC 18 - Double Star Pegasus - 00:09:23 27:43:56 NGC 19 - Galaxy Andromeda 13.3 00:10:41 32:58:58 NGC 20 See NGC 6 Galaxy Andromeda 13.1 00:09:33 33:18:32 NGC 21 NGC 29 Galaxy Andromeda 12.7 00:10:47 33:21:07 NGC 22 - Galaxy Pegasus 13.6 00:09:48 27:49:58 NGC 23 - Galaxy Pegasus 12.0 00:09:53 25:55:26 NGC 24 - Galaxy Sculptor 11.6 00:09:56 -24:57:52 NGC 25 - Galaxy Phoenix 13.0 00:09:59 -57:01:13 NGC 26 - Galaxy Pegasus 12.9 00:10:26 25:49:56 NGC 27 - Galaxy Andromeda 13.5 00:10:33 28:59:49 NGC 28 - Galaxy Phoenix 13.8 00:10:25 -56:59:20 NGC 29 See NGC 21 Galaxy Andromeda 12.7 00:10:47 33:21:07 NGC 30 - Double Star Pegasus - 00:10:51 21:58:39
  • Dynamics of Hot Gas in Galaxies, Groups, & Clusters

    Dynamics of Hot Gas in Galaxies, Groups, & Clusters

    DynamicsDynamics ofof hothot gasgas inin Galaxies,Galaxies, Groups,Groups, && ClustersClusters Bill Mathews Colleagues: Fabrizio Brighenti (Bologna) David Buote (UC Irvine) X-ray images of groups and clusters of galaxies Conventional cooling flows Evidence that cooling flows are not cooling as expected Proposed explanations why cooling flows aren’t cooling Heating cluster gas with AGN energy by dissipation of weak shock waves by PdV work as X-ray cavities form Cosmic ray buoyancy and outward gas circulation TypicalTypical HotHot GasGas ParametersParameters E galaxies rich galaxy & groups clusters Temperature 107 108 K X-ray luminosity 1039-44 1043-46 erg/s Fe abundance 0.4-1.0 0.4 solar 12-13 14-15 Total mass 10 10 Msun Baryon fraction < 0.16 ~0.16 XMMXMM ImageImage ofof PerseusPerseus ClusterCluster X-ray contours kpc 220 200ks Chandra image is here (Churazov et al. 2003) Central active cD galaxy 14 virial mass: Mvir = 8.5x10 Msun NGC 1275 DeepDeep 200ks200ks ChandraChandra ImageImage ofof PerseusPerseus ClusterCluster X-ray cavities -- bubbles (Fabian et al. 2003) Distance 73 Mpc 45 Lx 10 erg/s kpc 22 22 Absorption from foreground gas in merging galaxy Deprojected Deprojected XMM Observationsof XMM Observationsof this region affected by AGN core emission (Churazov Perseus Perseus et al.2003) averaged azimuthally Cluster Cluster 200ks Chandra Observations in Perseus strange radial abundance gradients less accurate only Ne peaks less accurate in the core 0 r (kpc) 120 (Sanders et al. 2004) Many elements have strange off-center peaks Abundance patterns are similar in Virgo (M87) ChandraChandra andand RadioRadio ImagesImages ofof PerseusPerseus radio contours (Fabian et al.
  • The Herschel Virgo Cluster Survey XVIII

    The Herschel Virgo Cluster Survey XVIII

    A&A 574, A126 (2015) Astronomy DOI: 10.1051/0004-6361/201424866 & c ESO 2015 Astrophysics The Herschel Virgo Cluster Survey XVIII. Star-forming dwarf galaxies in a cluster environment M. Grossi1,2,3,L.K.Hunt4,S.C.Madden5, T. M. Hughes6,R.Auld7, M. Baes6,G.J.Bendo8,S.Bianchi4, L. Bizzocchi1,9, M. Boquien10,A.Boselli11,M.Clemens12,E.Corbelli4,L.Cortese13,J.Davies7, I. De Looze6, S. di Serego Alighieri4, J. Fritz6, C. Pappalardo1,2,3, D. Pierini14, A. Rémy-Ruyer5,M.W.L.Smith7, J. Verstappen6, S. Viaene6, and C. Vlahakis15 1 Centro de Astronomia e Astrofísica da Universidade de Lisboa, OAL, Tapada da Ajuda, 1349-018 Lisbon, Portugal e-mail: [email protected] 2 Instituto de Astrofísica e Ciências do Espaço, Universidade de Lisboa, OAL, Tapada da Ajuda, 1349-018 Lisbon, Portugal 3 Departamento de Física, Faculdade de Ciências, Universidade de Lisboa, Edifício C8, Campo Grande, 1749-016 Lisbon, Portugal 4 INAF – Osservatorio Astrofisico di Arcetri, Largo Enrico Fermi 5, 50125 Firenze, Italy 5 Laboratoire AIM, CEA/DSM – CNRS – Université Paris Diderot, Irfu/Service d’Astrophysique, CEA Saclay, 91191 Gif-sur-Yvette, France 6 Sterrenkundig Observatorium, Universiteit Gent, Krijgslaan 281, 9000 Gent, Belgium 7 School of Physics and Astronomy, Cardiff University, Queens Buildings, The Parade, Cardiff CF24 3AA, UK 8 UK ALMA Regional Centre Node, Jodrell Bank Centre for Astrophysics, School of Physics and Astronomy, University of Manchester, Oxford Road, Manchester M13 9PL, UK 9 Center for Astrochemical Studies, Max-Planck-Institut für extraterrestrische Physik (MPE), Giessenbachstraße, 85748 Garching, Germany 10 Institute of Astronomy, University of Cambridge, Madingley Road, Cambridge CB3 0HA, UK 11 Laboratoire d’Astrophysique de Marseille, UMR 6110 CNRS, 38 rue F.
  • Properties of Brightest Cluster Galaxies As a Function of Cluster Classification Type

    Properties of Brightest Cluster Galaxies As a Function of Cluster Classification Type

    J. Korean Earth Sci. Soc., v. 36, no. 5, p. 427−436, September 2015 ISSN 1225-6692 (printed edition) http://dx.doi.org/10.5467/JKESS.2015.36.5.427 ISSN 2287-4518 (electronic edition) Properties of Brightest Cluster Galaxies as a Function of Cluster Classification Type 1,2 1, Heungjin Eom and Hyunjin Shim * 1 Department of Earth Science Education, Kyungpook National University, 80 Daehak-ro, Buk-gu, Daegu 702-701, Korea 2 Gunwi High School, 254-6 Guncheong-ro, Gunwi-up, Gunwi-gun, Kyungsangbukdo 716-801, Korea Abstract: We classified Abell clusters using the magnitude differences between two or three bright member galaxies and investigated how such classification was correlated with the properties of brightest cluster galaxies (BCGs). S-type BCGs being clearly brighter than the rest of the member galaxies were likely to be red, luminous, and evolved as early type galaxies. On the other hand, T-type BCGs being not dominant at all were less luminous than early type galaxies. A small fraction of BCGs was currently forming stars, and all of the star-forming BCGs were T-type BCGs. Active galactic nuclei were most frequent for S-type BCGs. Through these quantitative analyses of the BCG properties, we discussed the possible scenario of BCG formation and the differences between S-type and T-type of BCGs. Keywords: galaxy clusters, brightest cluster galaxy, galaxy evolution Introduction 1986). BCGs are elliptical galaxies (Dubinski, 1998), which are further divided into several types; gE, D, Es Recent studies have shown that environment plays and cD galaxies (Kormendy, 1989). These are in an important role for a galaxy to evolve and grow general the most massive galaxy that reside in the (e.g., Bahcall et al., 2003; De Lucia et al., 2006).