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Dark and Luminous Matter in Bright Spiral Galaxies

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Dark and Luminous Matter in Bright Spiral Galaxies DISSERTATION Presented in Partial Ful¯llment of the Requirements for the Degree Doctor of Philosophy in the Graduate School of The Ohio State University By Susan Alice Joan Kassin ***** The Ohio State University 2004 Dissertation Committee: Approved by Professor Richard Pogge, Adviser Professor Bradley Peterson Adviser Astronomy Graduate Program Professor Christopher Kochanek Professor Jay Frogel ABSTRACT I present photometrically calibrated images and surface photometry in the B; V; R; J; H; and K-bands of 26, and in the g, r, and K-bands of 5 nearby bright o (BT < 12:5 mag) spiral galaxies with inclinations between 30{65 degrees spanning the Hubble Sequence from Sa to Scd. Data are from The Ohio State University Bright Spiral Galaxy Survey, the Two Micron All Sky Survey, and the Sloan Digital Sky Survey Second Data Release. Radial surface brightness pro¯les are extracted, and integrated magnitudes are measured from the pro¯les. Axis ratios, position angles, and scale lengths are measured from the near-infrared. A 1-dimensional bulge/disk decomposition is performed on galaxies with a non-negligable bulge component. Radial stellar mass distributions are estimated by applying color-M=L relations derived from spectrophotometric spiral galaxy evolution models to the photometry. When available, radial gas masses are added to the radial stellar mass distributions to produce radial baryonic mass distributions. For each galaxy, a rotation curve due to its radial baryonic mass distribution is calculated, taking into account both the bulge and disk components when necessary. All of the galaxies have high-quality ii rotation curves available in the literature which allows us to calculate radial dark matter distributions for each galaxy by comparison with the baryonic mass rotation curves. Most galaxies are found to have maximal stellar disks, but seven are found to be submaximal in their inner parts (inner ¯ve scale radii). The following quantities are derived to characterize the radial baryonic and dark matter content of galaxies, and are found to correlate with Hubble Type: the peak velocity of the baryonic rotation curve (V¤;max), the radius at which the dark matter contributes 10% to the observed rotation curve (R10), and the radius at which dark matter contributes 50% 2 2 (RX ). From the radial distribution of ¯(r) ´ V¤ (r)=Vtot(r), I ¯nd that although the behavior of the dark matter distributions are qualitatively similar from galaxy to galaxy, there is systematic scatter among them to argue against a universal rotation curve. The general qualitative shape the ¯(r) curves is what is expected from an exponential baryonic disk and a rotation curve that is nearly flat at large radii. iii Dedicated to Prof. Joe Patterson who knew enough to send a freshman to Chile. iv ACKNOWLEDGMENTS I would like to thank my adviser Dr. Richard Pogge for his untiring advice, patience, and, of course, computer support. I would also like to thank Dr. Roelof de Jong for his advice, patience, productive collaboration in Baltimore, and for that memorable dinner with N, F, and W. Thank you Dr. Jay Frogel for creating the Ohio State University Bright Spiral Galaxy Survey, for providing me with some good scotch to make it go down easier, and for marrying Dr. Susana Deustua who made me visit the AAS Job Center in Atlanta which ultimately got me my job at UCSC (thanks Susanna). I would like to thank my closest friends for their untiring love and support: the Rasta Chimweme \Silver Bullet" Mphande, Robert \Laphroaig 20-yr" Farrell, Geraldine \Barbie" O'Brien, the one and only Brad Neuberg, and Mme. Louise Powers (in order of response time to my phone-mail messages-ha!). Thanks to Drs. Joe Patterson and Marc Kamionkowski for your inspiration at Columbia. I would also like to thank The Ohio State University Department of Astronomy, especially Dr. Brad Peterson and James Pizagno for their support and encouragement v and Dr. Andy Gould for admitting me to the graduate program. Thank you Benne Holwerda for your friendship, encouragement, and Benne-breaks. I wouldn't have survived Baltimore without you! Thanks to Dr. Carol Christian, Prof. C.D., and Sra. Summer for letting me stay at the \resort" in Baltimore. Thank you Nicole Marie for letting me watch Sibyl in your beautiful apartment! Thank you Yoni Hucke Atan and of course Mahina. And, thank you Blackie's chai and the gang at Shi-sha for keeping me out of trouble. I would like to thank the astronomers who provided copies of their galaxy rotation curves in tabular form via email: Kor Begeman, Gianfranco Gentile, Thilo Kranz, Povilas Palunas, Stuart Ryder, Michele Thornley, and Wilfred Walsh. I would also like to thank Marc Verheijen for making available his high-quality imaging and rotation curves of galaxies in the Ursa Major cluster. I thank the CTIO TAC for generous allocation of time for the OSU Galaxy Survey and the many people over the years who helped collect these observations. Funding for the OSU Bright Spiral Galaxy Survey was provided by grants from The National Science Foundation (grants AST-9217716 and AST-9617006), with additional funding by The Ohio State University. I would like to acknowledge ¯nancial support from The Space Telescope Science Institute Director's Discretionary Research Fund (DDRF) which was invaluable in allowing me to study with Roelof de Jong at Space Telescope. vi This research makes use of data from both the Sloan Digital Sky Survey and the Two Micron All Sky Survey. The Two Micron All Sky Survey was a joint project of the University of Massachusetts and the Infrared Processing and Analysis Center/California Institute of Technology, funded by the National Aeronautics and Space Administration and the National Science Foundation. Funding for the creation and distribution of the SDSS Archive has been provided by the Alfred P. Sloan Foundation, the Participating Institutions, the National Aeronautics and Space Administration, the National Science Foundation, the U.S. Department of Energy, the Japanese Monbukagakusho, and the Max Planck Society. SDSS is managed by the Astrophysical Research Consortium (ARC) for the Participating Institutions: The University of Chicago, Fermilab, the Institute for Advanced Study, the Japan Participation Group, The Johns Hopkins University, Los Alamos National Laboratory, the Max-Planck-Institute for Astronomy (MPIA), the Max-Planck-Institute for Astrophysics (MPA), New Mexico State University, University of Pittsburgh, Princeton University, the United States Naval Observatory, and the University of Washington. I also made use of NASA's Astrophysics Data System, the NASA/IPAC Extragalactic Database (NED), the HyperLeda database, and the VizieR catalog. NED is operated by the Jet Propulsion Laboratory, California Institute of Technology, under contract with NASA, and HyperLeda database and VizieR are operated by the CDS in Strasbourg, France. vii VITA November 18, 1977 . Born { Manhasset, New York 1999 . B.A. Physics, Columbia College, Columbia University 1999 { 2000 . Distinguished University Graduate Fellow, The Ohio State University 2002 . M.S. Astronomy, The Ohio State University 2000 { 2004 . Graduate Teaching and Research Associate, The Ohio State University PUBLICATIONS Research Publications 1. S. A. Kassin, J. A. Frogel, R. W. Pogge, G. P. Tiede, and K. Sellgren, \Stellar Populations in NGC 4038/39 (the Antennae): Exploring a Galaxy Merger Pixel by Pixel", AJ, 126, 1276, (2003). 2. J. P. Halpern, R. Uglesich, N. Mirabal, S. Kassin, J. Thorstensen, W. C. Keel, A. Diercks, J. S. Bloom, F. Harrison, J. Mattox, and M. Eracleous, \GRB 991216 Joins the Jet Set: Discovery and Monitoring of Its Optical Afterglow", ApJ, 543, 697, (2000). FIELDS OF STUDY Major Field: Astronomy viii Table of Contents Abstract . ii Dedication . iv Acknowledgments . v Vita . viii List of Tables . x List of Figures . xii 1 Introduction 1 1.1 Dark and Luminous Matter in Galaxies . 1 1.2 Relation to Previous Work . 5 1.3 Scope of the Dissertation . 8 2 Data Sample and Analysis 9 2.1 Data Sets . 9 2.2 Observation and Reduction of the OSUBSGS Galaxies . 11 2.3 Photometric Calibration . 13 2.3.1 OSUBSGS & 2MASS Galaxies . 13 2.3.2 SDSS DR2 Galaxies . 16 3 Surface Brightness Pro¯les and Physical Properties of the Galaxies 22 ix 3.1 Axis Ratios & Position Angles . 22 3.2 Radial Surface Brightness Pro¯les . 23 3.2.1 Bulge/Disk Decompositions . 25 3.3 Distances . 26 4 Radial Distributions of Baryonic and Dark Matter in Galaxies 43 4.1 Baryonic Matter . 44 4.1.1 Radial Baryonic Surface Mass-Density Distributions . 44 4.1.2 Baryonic Rotation Curves . 46 4.1.3 Uncertainties in Baryonic Rotation Curves . 47 4.1.4 E®ects Due to Dust . 48 4.2 Dark Matter . 51 4.2.1 Observed Rotation Curves . 51 4.2.2 Dark Matter Rotation Curves . 53 4.2.3 Uncertainties in Dark Matter Rotation Curves . 53 5 Baryonic and Dark Matter Properties 68 5.1 Maximal and Non-Maximal Disks . 68 5.2 Dark and Baryonic Matter Correlations . 70 5.3 Radial Behavior of Dark Matter . 72 6 Conclusions 81 Bibliography 82 x List of Tables 2.1 Basic parameters of the sample galaxies. 17 2.1 Basic parameters of the sample galaxies. 18 2.2 Observational Details for the OSUBSGS Galaxies . 19 2.2 Observational Details for the OSUBSGS Galaxies . 20 2.2 Observational Details for the OSUBSGS Galaxies . 21 3.1 Measured Galaxy Parameters . 34 3.1 Measured Galaxy Parameters . 35 3.1 Measured Galaxy Parameters . 36 3.1 Measured Galaxy Parameters . 37 3.1 Measured Galaxy Parameters . 38 3.1 Measured Galaxy Parameters . 39 3.1 Measured Galaxy Parameters . 40 3.2 Bulge/Disk Parameters for K-band Images . 41 3.2 Bulge/Disk Parameters for K-band Images .
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  • Lopsided Spiral Galaxies: Evidence for Gas Accretion

    Lopsided Spiral Galaxies: Evidence for Gas Accretion

    A&A 438, 507–520 (2005) Astronomy DOI: 10.1051/0004-6361:20052631 & c ESO 2005 Astrophysics Lopsided spiral galaxies: evidence for gas accretion F. Bournaud1, F. Combes1,C.J.Jog2, and I. Puerari3 1 Observatoire de Paris, LERMA, 61 Av. de l’Observatoire, 75014 Paris, France e-mail: [email protected] 2 Department of Physics, Indian Institute of Science, Bangalore 560012, India 3 Instituto Nacional de Astrofísica, Optica y Electrónica, Calle Luis Enrique Erro 1, 72840 Tonantzintla, Puebla, Mexico Received 3 January 2005 / Accepted 15 March 2005 Abstract. We quantify the degree of lopsidedness for a sample of 149 galaxies observed in the near-infrared from the OSUBGS sample, and try to explain the physical origin of the observed disk lopsidedness. We confirm previous studies, but for a larger sample, that a large fraction of galaxies have significant lopsidedness in their stellar disks, measured as the Fourier amplitude of the m = 1 component normalised to the average or m = 0 component in the surface density. Late-type galaxies are found to be more lopsided, while the presence of m = 2 spiral arms and bars is correlated with disk lopsidedness. We also show that the m = 1 amplitude is uncorrelated with the presence of companions. Numerical simulations were carried out to study the generation of m = 1viadifferent processes: galaxy tidal encounters, galaxy mergers, and external gas accretion with subsequent star formation. These simulations show that galaxy interactions and mergers can trigger strong lopsidedness, but do not explain several independent statistical properties of observed galaxies. To explain all the observational results, it is required that a large fraction of lopsidedness results from cosmological accretion of gas on galactic disks, which can create strongly lopsided disks when this accretion is asymmetrical enough.