A DIVERSITY OF PROGENITORS AND HISTORIES FOR ISOLATED SPIRAL GALAXIES

We analyze a suite of 33 cosmological simulations of the evolution of Milky-Way-mass galaxies in low-density environments. Our sample spans a broad range of Hubble types at z = 0, from nearly bulgeless disks to bulge-dominated galaxies. Despite the fact that a large fraction of the bulge is typically in place by z ∼ 1, we find no significant correlation between the morphology at z = 1 and at z = 0. The z = 1 progenitors of disk galaxies span a range of morphologies, including smooth disks, unstable disks, interacting galaxies, and bulge-dominated systems. By z ∼ 0.5, spiral arms and bars are largely in place and the progenitor morphology is correlated with the final morphology. We next focus on late-type galaxies with a bulge-to-total ratio (B/T) <0.3 at z = 0. These show a correlation between B/T at z = 0 and the mass ratio of the largest merger at z < 2, as well as with the gas accretion rate at z > 1. We find that the galaxies with the lowest B/T tend to have a quiet baryon input history, with no major mergers at z < 2, and with a low and constant gas accretion rate that keeps a stable angular-momentum direction. More violent merger or gas accretion histories lead to galaxies with more prominent bulges. Most disk galaxies have a bulge Sérsic index n ⩽ 2. The galaxies with the highest bulge Sérsic index tend to have histories of intense gas accretion and disk instability rather than active mergers.

[1]  A. Dekel,et al.  METALLICITY-DEPENDENT QUENCHING OF STAR FORMATION AT HIGH REDSHIFT IN SMALL GALAXIES , 2011, 1106.0301.

[2]  L. Ho,et al.  THICK DISKS OF EDGE-ON GALAXIES SEEN THROUGH THE SPITZER SURVEY OF STELLAR STRUCTURE IN GALAXIES (S4G): LAIR OF MISSING BARYONS? , 2011, 1108.0037.

[3]  Lucio Mayer,et al.  FORMING REALISTIC LATE-TYPE SPIRALS IN A ΛCDM UNIVERSE: THE ERIS SIMULATION , 2011, 1103.6030.

[4]  O. Valenzuela,et al.  THE SPECIFIC STAR FORMATION RATE AND STELLAR MASS FRACTION OF LOW-MASS CENTRAL GALAXIES IN COSMOLOGICAL SIMULATIONS , 2011, 1103.4422.

[5]  Andreas Burkert,et al.  SHORT-LIVED STAR-FORMING GIANT CLUMPS IN COSMOLOGICAL SIMULATIONS OF z ≈ 2 DISKS , 2010, 1011.0433.

[6]  C. Brook,et al.  INTERPRETING THE EVOLUTION OF THE SIZE–LUMINOSITY RELATION FOR DISK GALAXIES FROM REDSHIFT 1 TO THE PRESENT , 2010, 1011.0432.

[7]  Ralf Bender,et al.  BULGELESS GIANT GALAXIES CHALLENGE OUR PICTURE OF GALAXY FORMATION BY HIERARCHICAL CLUSTERING, , 2010, 1009.3015.

[8]  R. Genzel,et al.  THE STRUCTURE OF GRAVITATIONALLY UNSTABLE GAS-RICH DISK GALAXIES , 2010, 1007.0169.

[9]  Princeton University.,et al.  A COMPREHENSIVE ANALYSIS OF UNCERTAINTIES AFFECTING THE STELLAR MASS–HALO MASS RELATION FOR 0 < z < 4 , 2010, 1001.0015.

[10]  D. Elbaz,et al.  VERY HIGH GAS FRACTIONS AND EXTENDED GAS RESERVOIRS IN z = 1.5 DISK GALAXIES , 2009, 0911.2776.

[11]  E. Quataert,et al.  THE DISRUPTION OF GIANT MOLECULAR CLOUDS BY RADIATION PRESSURE & THE EFFICIENCY OF STAR FORMATION IN GALAXIES , 2009, 0906.5358.

[12]  R. Teyssier,et al.  MORPHOLOGICAL QUENCHING OF STAR FORMATION: MAKING EARLY-TYPE GALAXIES RED , 2009, 0905.4669.

[13]  R. Somerville,et al.  CONSTRAINTS ON THE RELATIONSHIP BETWEEN STELLAR MASS AND HALO MASS AT LOW AND HIGH REDSHIFT , 2009, 0903.4682.

[14]  D. Fisher,et al.  BULGES OF NEARBY GALAXIES WITH SPITZER: THE GROWTH OF PSEUDOBULGES IN DISK GALAXIES AND ITS CONNECTION TO OUTER DISKS , 2009, 0902.3258.

[15]  Daniel Ceverino,et al.  FORMATION OF MASSIVE GALAXIES AT HIGH REDSHIFT: COLD STREAMS, CLUMPY DISKS, AND COMPACT SPHEROIDS , 2009, 0901.2458.

[16]  B. Garilli,et al.  THE DEPENDENCE OF STAR FORMATION ACTIVITY ON STELLAR MASS SURFACE DENSITY AND SERSIC INDEX IN zCOSMOS GALAXIES AT 0.5 < z < 0.9 COMPARED WITH SDSS GALAXIES AT 0.04 < z < 0.08 , 2009, 0901.0550.

[17]  Andreas Burkert,et al.  BULGE n AND B/T IN HIGH-MASS GALAXIES: CONSTRAINTS ON THE ORIGIN OF BULGES IN HIERARCHICAL MODELS , 2008, 0807.0040.

[18]  Lars Hernquist,et al.  HOW DO DISKS SURVIVE MERGERS? , 2008, 0806.1739.

[19]  Laboratoire AIM,et al.  Bulge Formation by the Coalescence of Giant Clumps in Primordial Disk Galaxies , 2008, 0903.1937.

[20]  S. Rabien,et al.  From Rings to Bulges: Evidence for Rapid Secular Galaxy Evolution at z ~ 2 from Integral Field Spectroscopy in the SINS Survey , 2008, 0807.1184.

[21]  L. Moustakas,et al.  Cold Dark Matter Substructure and Galactic Disks. I. Morphological Signatures of Hierarchical Satellite Accretion , 2007, 0708.1949.

[22]  Chien Y. Peng,et al.  An Explanation for the Observed Weak Size Evolution of Disk Galaxies , 2006, astro-ph/0612428.

[23]  B. G. Elmegreen,et al.  Rapid Formation of Exponential Disks and Bulges at High Redshift from the Dynamical Evolution of Clump-Cluster and Chain Galaxies , 2007, 0708.0306.

[24]  E. Athanassoula,et al.  Structure Formation inside Triaxial Dark Matter Halos: Galactic Disks, Bulges, and Bars , 2007, 0706.3895.

[25]  A. Cimatti,et al.  Multiwavelength Study of Massive Galaxies at z~2. I. Star Formation and Galaxy Growth , 2007, 0705.2831.

[26]  S. Ravindranath,et al.  Resolved Galaxies in the Hubble Ultra Deep Field: Star Formation in Disks at High Redshift , 2007, astro-ph/0701121.

[27]  S. Jogee,et al.  Characterizing Bars at z ~ 0 in the Optical and NIR: Implications for the Evolution of Barred Disks with Redshift , 2006, astro-ph/0608039.

[28]  P. Hopkins,et al.  The Kinematic Structure of Merger Remnants , 2006, astro-ph/0607446.

[29]  The secular evolution of disk structural parameters , 2005, astro-ph/0509310.

[30]  Carnegie-Mellon,et al.  A Merger-driven Scenario for Cosmological Disk Galaxy Formation , 2005, astro-ph/0503369.

[31]  Chien Y. Peng,et al.  GEMS: The Surface Brightness and Surface Mass Density Evolution of Disk Galaxies , 2005 .

[32]  B. Elmegreen,et al.  Galaxy Morphologies in the Hubble Ultra Deep Field: Dominance of Linear Structures at the Detection Limit , 2005, astro-ph/0508216.

[33]  C. Conselice,et al.  The Assembly of Diversity in the Morphologies and Stellar Populations of High-Redshift Galaxies , 2005, astro-ph/0501088.

[34]  Casey Papovich,et al.  The Luminosity, Stellar Mass, and Number Density Evolution of Field Galaxies of Known Morphology from z = 0.5 to 3 , 2004, astro-ph/0405001.

[35]  A. Cimatti,et al.  A New Photometric Technique for the Joint Selection of Star-forming and Passive Galaxies at 1.4 ≲ z ≲ 2.5 , 2004, astro-ph/0409041.

[36]  T. Naab,et al.  Statistical Properties of Collisionless Equal- and Unequal-Mass Merger Remnants of Disk Galaxies , 2001, astro-ph/0110179.

[37]  M. Steinmetz,et al.  Simulations of Galaxy Formation in a Λ Cold Dark Matter Universe. I. Dynamical and Photometric Properties of a Simulated Disk Galaxy , 2002, astro-ph/0211331.

[38]  B. Elmegreen.  Star Formation from Galaxies to Globules , 2001, astro-ph/0207114.

[39]  Early Evolution of Disk Galaxies: Formation of Bulges in Clumpy Young Galactic Disks , 1998, astro-ph/9806355.

[40]  Jr.,et al.  The Global Schmidt law in star forming galaxies , 1997, astro-ph/9712213.

[41]  D. Eisenstein,et al.  HOP: A New Group-finding Algorithm for N-Body Simulations , 1997, astro-ph/9712200.