The Assembly History of Field Spheroidals: Evolution of Mass-to-Light Ratios and Signatures of Recent Star Formation

We present a comprehensive catalog of high signal-to-noise ratio spectra obtained with DEIMOS on the Keck II telescope for a sample of F850LP 2 for high-mass spheroidals and zf ~ 1.2 for lower mass systems, a more realistic picture is that most of the stellar mass formed in all systems at z > 2 with subsequent activity continuing to lower redshifts (z < 1.2). The fraction of stellar mass formed at recent times depends strongly on galactic mass, ranging from <1% for masses above 1011.5 M☉ to 20%-40% below 1011 M☉. Independent support for recent activity is provided by spectroscopic ([O II] emission, Hδ) and photometric (blue cores and broadband colors) diagnostics. Via the analysis of a large sample with many independent diagnostics, we are able to reconcile previously disparate interpretations of the assembly history of field spheroidals. We discuss the implications of this measurement for the determination of the evolution of the number density of E+S0 galaxies, suggesting that number density evolution of the morphologically selected population has occurred since z ~ 1.2.

[1]  Cambridge,et al.  ∼ 4 and the Evolution of the Uv Luminosity Density at High Redshift , 2022 .

[2]  S. C. Trager,et al.  The Stellar Population Histories of Local Early-Type Galaxies. I. Population Parameters , 2000, astro-ph/0001072.

[3]  The K20 survey. VI. The distribution of the stellar masses in galaxies up to z 2 , 2004, astro-ph/0405055.

[4]  H. Rix,et al.  The Fundamental Plane of Field Early-Type Galaxies at z = 1 , 2003, astro-ph/0312230.

[5]  Henry C. Ferguson,et al.  Accepted for publication in the Astrophysical Journal Preprint typeset using L ATEX style emulateapj v. 19/02/01 THE STELLAR POPULATIONS AND EVOLUTION OF LYMAN BREAK GALAXIES 1 , 2001 .

[6]  J. Kormendy.  in Nearly Normal Galaxies , 1986 .

[7]  J. Lehár,et al.  The Fundamental Plane of Gravitational Lens Galaxies and The Evolution of Early-Type Galaxies in Low-Density Environments , 1999, astro-ph/9909018.

[8]  C. Conselice,et al.  The Evolution of Early-Type Field Galaxies Selected from a NICMOS Map of the Hubble Deep Field North , 2003, astro-ph/0310231.

[9]  The optical—infrared colour distribution of a statistically complete sample of faint field spheroidal galaxies , 1998, astro-ph/9811465.

[10]  S. Djorgovski,et al.  Fundamental Properties of Elliptical Galaxies , 1987 .

[11]  A NICMOS Search for High-Redshift Elliptical Galaxy Candidates* , 1999, astro-ph/9907178.

[12]  C. S. Frenk,et al.  The Epoch of Galaxy Formation , 1997, astro-ph/9703111.

[13]  I. Jørgensen,et al.  The Fundamental Plane for cluster E and S0 galaxies , 1995, astro-ph/9511139.

[14]  The DEEP Groth Strip Survey. X. Number Density and Luminosity Function of Field E/S0 Galaxies at z < 1 , 2000, astro-ph/0011092.

[15]  E. Bertin,et al.  SExtractor: Software for source extraction , 1996 .

[16]  A. Comastri,et al.  The 2-10 keV luminosity as a Star Formation Rate indicator , 2003 .

[17]  Karl Glazebrook,et al.  The morphologies of distant galaxies. II. Classifications from the Hubble Space Telescope medium deep survey , 1996 .

[18]  M. Giavalisco,et al.  The Great Observatories Origins Deep Survey: Initial results from optical and near-infrared imaging , 2003, astro-ph/0309105.

[19]  Old galaxies in the young Universe , 2004, Nature.

[20]  R. Davies,et al.  Spectroscopy and photometry of elliptical galaxies. I: a new distance estimator , 1987 .

[21]  M. Stiavelli,et al.  Estimating distances to elliptical galaxies with a mass-luminosity relation , 1995 .

[22]  T. Treu,et al.  Massive Dark Matter Halos and Evolution of Early-Type Galaxies to z ≈ 1 , 2004, astro-ph/0401373.

[23]  G. Zamorani,et al.  The Scaling Relations of Galaxy Clusters and Their Dark Matter Halos , 2003, astro-ph/0307141.

[24]  R. Ellis,et al.  Precision photometry of early-type galaxies in the Coma and Virgo clusters: a test of the universality of the colour–magnitude relation – II. Analysis , 1992 .

[25]  P. Dokkum,et al.  The Fundamental Plane and the evolution of the M/L ratio of early-type field galaxies up to z ∼ 1 , 2002, astro-ph/0211566.

[26]  Keck spectroscopy of distant GOODS spheroidal galaxies: Downsizing in a hierarchical Universe , 2005, astro-ph/0502028.

[27]  R. Ellis,et al.  Evidence for evolving spheroidals in the Hubble Deep Fields North and South , 2000, astro-ph/0007114.

[28]  T. Ponman,et al.  X-ray scaling properties of early-type galaxies , 2003, astro-ph/0301153.

[29]  M. Fukugita,et al.  The Sloan Digital Sky Survey Photometric System , 1996 .

[30]  L. Ho,et al.  Detailed structural decomposition of galaxy images , 2002, astro-ph/0204182.

[31]  Cambridge,et al.  The star formation rate of the Universe at z~ 6 from the Hubble Ultra-Deep Field , 2004, astro-ph/0403223.

[32]  G. Kauffmann,et al.  The spatial and kinematic distributions of cluster galaxies in a ΩCDM universe: comparison with observations , 2000, astro-ph/0005485.

[33]  J. Newman,et al.  The Team Keck Treasury Redshift Survey of the GOODS-North Field , 2004, astro-ph/0401353.

[34]  L. Cowie,et al.  New Insight on Galaxy Formation and Evolution from Keck Spectroscopy of the Hawaii Deep Fields , 1996, astro-ph/9606079.

[35]  A. Dressler,et al.  Clusters of Galaxies : Probes of Cosmological Structure and Galaxy Evolution , 2022 .

[36]  T. Treu,et al.  The Structure and Dynamics of Luminous and Dark Matter in the Early-Type Lens Galaxy of 0047–281 at z = 0.485 , 2002, astro-ph/0205281.

[37]  R. Bouwens,et al.  Internal Color Properties of Resolved Spheroids in the Deep Hubble Space Telescope Advanced Camera for Surveys Field of UGC 10214 , 2004 .

[38]  B. Lanzoni,et al.  The tilt of the fundamental plane of elliptical galaxies — I. Exploring dynamical and structural effects , 1996, astro-ph/9601100.

[39]  R. Nichol,et al.  Early-Type Galaxies in the Sloan Digital Sky Survey. III. The Fundamental Plane , 2003, astro-ph/0301626.

[40]  T. Treu,et al.  The Internal Structure and Formation of Early-Type Galaxies: The Gravitational Lens System MG 2016+112 at z = 1.004 , 2002, astro-ph/0202342.

[41]  Simon D. M. White,et al.  Chemical enrichment of the intracluster and intergalactic medium in a hierarchical galaxy formation model , 2003, astro-ph/0310268.

[42]  J. Dunlop,et al.  Premature dismissal of high‐redshift elliptical galaxies , 1998, astro-ph/9812222.

[43]  The Origin of Blue Cores in Hubble Deep Field E/S0 Galaxies , 2001, astro-ph/0110008.

[44]  I. Jørgensen,et al.  Spectroscopy for E and S0 galaxies in nine clusters , 1995 .

[45]  S. Faber,et al.  Global Scaling Relations for Elliptical Galaxies and Implications for Formation , 1987 .

[46]  J. Brinchmann,et al.  The Mass Assembly and Star Formation Characteristics of Field Galaxies of Known Morphology , 2000, The Astrophysical journal.

[47]  P. Dokkum,et al.  Morphological Evolution and the Ages of Early-Type Galaxies in Clusters , 2001, astro-ph/0101468.

[48]  G. Kauffmann.  The Ages of elliptical galaxies in a merger model , 1995 .

[49]  On the continuous formation of field spheroidal galaxies in hierarchical models of structure formation , 2001, astro-ph/0110387.

[50]  Self-similar Models for the Mass Profiles of Early-Type Lens Galaxies , 2003, astro-ph/0306096.

[51]  P. Dokkum,et al.  The Fundamental Plane at z = 1.27: First Calibration of the Mass Scale of Red Galaxies at Redshifts z > 1 , 2002, astro-ph/0210643.

[52]  The evolution of early-type galaxies in distant clusters. III. M/L-v ratios in the z=0.33 cluster Cl 1358+62 , 1999, astro-ph/9906152.

[53]  D. Coe,et al.  The Nature of Blue Cores in Spheroids: A Possible Connection with Active Galactic Nuclei and Star Formation , 2004, astro-ph/0411125.

[54]  R. Bender,et al.  Dynamically hot galaxies. I - Structural properties , 1992 .

[55]  J. Kneib,et al.  A Wide-Field Hubble Space Telescope Study of the Cluster Cl 0024+16 at z = 0.4. I. Morphological Distributions to 5 Mpc Radius , 2003, astro-ph/0303267.

[56]  A. Fruchter,et al.  HIGH-REDSHIFT GALAXIES IN THE HUBBLE DEEP FIELD : COLOUR SELECTION AND STAR FORMATION HISTORY TO Z 4 , 1996, astro-ph/9607172.

[57]  R. Ellis,et al.  ACCEPTED FOR PUBLICATION IN ASTROPHYSICAL JOURNAL LETTERS Preprint typeset using L ATEX style emulateapj v. 25/04/01 ON THE ASSEMBLY HISTORY OF EARLY-TYPE GALAXIES IN THE HUBBLE DEEP FIELD NORTH 1,2 , 2003 .

[58]  M. Franx.  CONSTRAINING GALAXY EVOLUTION AND COSMOLOGY FROM GALAXY KINEMATICS: FIRST OBSERVATIONS AT Z=0.18 , 1993 .

[59]  P. Dokkum,et al.  A JavaScript Passive Evolution Calculator , 2005, astro-ph/0501236.

[60]  I. Hook,et al.  A high abundance of massive galaxies 3–6 billion years after the Big Bang , 2004, Nature.

[61]  D. M. Alexander,et al.  Optical and Infrared Properties of the 2 Ms Chandra Deep Field North X-Ray Sources , 2003, astro-ph/0306212.

[62]  U. California,et al.  Semi-analytic modelling of galaxy formation: The local Universe , 1998, astro-ph/9802268.

[63]  V. Marel,et al.  Velocity profiles of galaxies with claimed black holes – III. Observations and models for M87 , 1994 .

[64]  D. Kelson,et al.  The Detailed Fundamental Plane of Two High-Redshift Clusters: MS 2053–04 at z = 0.58 and MS 1054–03 at z = 0.83 , 2003, astro-ph/0312236.

[65]  Marc Davis,et al.  Science Objectives and Early Results of the DEEP2 Redshift Survey , 2002, SPIE Astronomical Telescopes + Instrumentation.

[66]  D. M. Alexander,et al.  The Chandra Deep Field North Survey. XIII. 2 Ms Point-Source Catalogs , 2003, astro-ph/0304392.

[67]  T. Treu,et al.  The properties of field elliptical galaxies at intermediate redshift — I. Empirical scaling laws , 1999 .

[68]  The Dark Matter Distribution in the Central Regions of Galaxy Clusters , 2003, astro-ph/0309465.

[69]  J. Lehár,et al.  The Evolution of a Mass-selected Sample of Early-Type Field Galaxies , 2002, astro-ph/0211229.

[70]  J. B. Oke.  Absolute spectral energy distributions for white dwarfs , 1974 .

[71]  David Burstein,et al.  Old Stellar Populations. VI. Absorption-Line Spectra of Galaxy Nuclei and Globular Clusters , 1997, astro-ph/9712258.

[72]  G. Bruzual,et al.  Stellar population synthesis at the resolution of 2003 , 2003, astro-ph/0309134.

[73]  The DEEP2 Galaxy Redshift Survey: Clustering of Galaxies in Early Data , 2003, astro-ph/0305586.

[74]  The properties of field elliptical galaxies at intermediate redshift — II. Photometry and spectroscopy of an HST-selected sample , 2001, astro-ph/0104177.

[75]  Marijn Franx,et al.  Submitted to ApJ Preprint typeset using L ATEX style emulateapj v. 5/14/03 THE REST-FRAME OPTICAL LUMINOSITY DENSITY, COLOR, AND STELLAR MASS DENSITY OF THE UNIVERSE FROM Z=0 TO Z=3 1 , 2003 .

[76]  G. Kauffmann.  The age of elliptical galaxies and bulges in a merger model , 1995, astro-ph/9502096.

[77]  The DEEP Groth Strip Survey. IX. Evolution of the Fundamental Plane of Field Galaxies , 2003, astro-ph/0307242.

[78]  C. Kochanek,et al.  The Evolution and Structure of Early-Type Field Galaxies: A Combined Statistical Analysis of Gravitational Lenses , 2004, astro-ph/0412001.

[79]  Robert C. Kennicutt,et al.  The Integrated spectra of nearby galaxies: General properties and emission line spectra , 1992 .

[80]  The Mass Assembly Histories of Galaxies of Various Morphologies in the GOODS Fields , 2005, astro-ph/0502204.

[81]  The Evolution of Early-Type Galaxies in Distant Clusters , 1995, astro-ph/9911065.

[82]  T. Treu,et al.  The redshift of the Einstein ring in MG 1549+305 , 2003 .

[83]  P. McCarthy.  Eros and Faint Red Galaxies , 2004 .

[84]  Heidelberg,et al.  Nearly 5000 Distant Early-Type Galaxies in COMBO-17: A Red Sequence and Its Evolution since z ~ 1 , 2003, astro-ph/0303394.

[85]  Duncan A. Forbes,et al.  A catalogue and analysis of X-ray luminosities of early-type galaxies , 2001 .

[86]  D. Fabricant,et al.  A Spectroscopic Survey of the Galaxy Cluster CL 1358+62 at z = 0.328 , 1998, astro-ph/9801137.

[87]  P. Schechter.  An analytic expression for the luminosity function for galaxies , 1976 .

[88]  P. Dokkum,et al.  The Fundamental Plane in CL 0024 at z = 0.4: implications for the evolution of the mass-to-light ratio , 1996, astro-ph/9603063.

[89]  R. Bouwens,et al.  The Luminosity Function of Early-Type Field Galaxies at z ≈ 0.75 , 2004, astro-ph/0407644.

[90]  Giuseppina Fabbiano,et al.  X-Ray Luminosity Function and Total Luminosity of Low-Mass X-Ray Binaries in Early-Type Galaxies , 2004 .

[91]  The properties of field elliptical galaxies at intermediate redshift – III. The Fundamental Plane and the evolution of stellar populations from z≈0.4 to z=0 , 2001, astro-ph/0106147.

[92]  Judith G. Cohen,et al.  Caltech Faint Galaxy Redshift Survey. XVI. The Luminosity Function for Galaxies in the Region of the Hubble Deep Field-North to z = 1.5 , 2001, astro-ph/0107107.