J/ApJ/817/87 Spectroscopy of luminous compact blue galaxies (Crawford+, 2016)
Spectroscopy of luminous compact blue galaxies in distant clusters.
II. Physical properties of dE progenitor candidates.
Crawford S.M., Wirth G.D., Bershady M.A., Randriamampandry S.M.
<Astrophys. J., 817, 87 (2016)>
=2016ApJ...817...87C 2016ApJ...817...87C (SIMBAD/NED BibCode)
ADC_Keywords: Clusters, galaxy ; Spectroscopy
Keywords: galaxies: clusters: general; galaxies: evolution
Abstract:
Luminous Compact Blue Galaxies (LCBGs) are an extreme star-bursting
population of galaxies that were far more common at earlier epochs
than today. Based on spectroscopic and photometric measurements of
LCBGs in massive (M>1015M☉), intermediate redshift (0.5<z<0.9)
galaxy clusters, we present their rest-frame properties including star
formation rate, dynamical mass, size, luminosity, and metallicity. The
appearance of these small, compact galaxies in clusters at
intermediate redshift helps explain the observed redshift evolution in
the size-luminosity relationship among cluster galaxies. In addition,
we find the rest-frame properties of LCBGs appearing in galaxy
clusters are indistinguishable from field LCBGs at the same redshift.
Up to 35% of the LCBGs show significant discrepancies between optical
and infrared indicators of star formation, suggesting that star
formation occurs in obscured regions. Nonetheless, the star formation
for LCBGs shows a decrease toward the center of the galaxy clusters.
Based on their position and velocity, we estimate that up to 10% of
cluster LCBGs are likely to merge with another cluster galaxy.
Finally, the observed properties and distributions of the LCBGs in
these clusters lead us to conclude that we are witnessing the
quenching of the progenitors of dwarf elliptical galaxies that
dominate the number density of present-epoch galaxy clusters.
Description:
Deep imaging data in UBRIz and two narrow bands were obtained with the
Mini-Mosaic camera from the WIYN 3.5 m telescope for all five clusters
between 1999 October and 2004 June. We obtained spectroscopic
observations for a sample of cluster star-forming galaxies with the
DEIMOS, Faber et al. 2003 on the Keck II Telescope during 2005 October
and 2007 April. The narrow-band filters were specifically designed to
detect [OII] λ3727 at the redshift of each cluster. All of the
clusters have been the target of extensive observations with the HST,
primarily using either WFPC2 or the Advanced Camera for Surveys (ACS).
For all measurements, we have attempted to select data taken in a
filter closest to the rest-frame B band. We have employed ACS imaging
data whenever possible and substituted WFPC2 images only when
required. For clusters observed in the far-infrared regime by the
Spitzer Space Telescope, we extracted MIPS 24µm flux densities,
S24, from images obtained through the Enhanced Imaging Products
archive.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 106 7 Summary of cluster observations
table2.dat 149 160 Measured properties of LCBGs
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See also:
J/ApJ/741/98 : Spectroscopy of galaxy clusters to find LCBGs
(Crawford+, 2011)
J/ApJ/708/1076 : The WHIQII survey: compact blue galaxies (Tollerud+, 2010)
J/ApJ/692/556 : Star forming galaxy templates (Rieke+, 2009)
J/ApJ/617/240 : Oxygen abundances in the GOODS-North field
(Kobulnicky+, 2004)
J/AJ/131/332 : Velocities of individual stars in NGC 205 (Geha+, 2006)
J/MNRAS/417/1996 : Gas properties in emission-line galaxies (Jaffe+, 2011)
J/MNRAS/335/10 : Hα survey of Abell 1689 (Balogh+, 2002)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 13 A13 --- Field Cluster field of the observations
15- 16 I2 h RAh [0/16] Hour of Right Ascension (J2000)
18- 19 I2 min RAm [4/57] Minute of Right Ascension (J2000)
21- 24 F4.1 s RAs [0/48.8] Second of Right Ascension (J2000)
26 A1 --- DE- Sign of the Declination (J2000)
27- 28 I2 deg DEd [3/43] Degree of Declination (J2000)
30- 31 I2 arcmin DEm [0/37] Arcminute of Declination (J2000)
33- 34 I2 arcsec DEs [16/51] Arcsecond of Declination (J2000)
36- 41 F6.4 --- z [0.5389/0.9005]? Measured cluster redshift
43- 46 I4 km/s sigP [806/1490]? Measured cluster projected
velocity dispersion
48- 50 I3 km/s e_sigP [47/167]? Error in sigP
52- 56 I5 --- PropID ? HST proposal ID
58- 62 A5 --- Inst HST instrument (ACS or WFPC2)
64- 67 I4 s ExpH [1500/4600]? HST typical exposure time
69- 74 A6 --- Filt HST filter (F814W, F775W, F850LP)
76- 79 I4 s ExpS [764/3218]? Spitzer mean exposure time
81- 82 I2 uJy rms [13/28]? Spitzer rms noise
84-106 A23 --- SEIP Spitzer Enhanced Image Product ID
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Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 19 A19 --- Field Field ("Field LCBG", "Cluster LCBG", or
"Cluster Blue Galaxy")
21- 24 A4 --- --- [WLTV]
26- 44 A19 --- WLTV WLTV designation (JHHMMSS.ss+DDMMSS.s,
<[CWB2011] WLTV JHHMMSS.ss+DDMMSS.s>
in SIMBAD)
46- 56 F11.7 deg RAdeg [4.55550/241.1995] Right Ascension (J2000)
58- 67 F10.7 deg DEdeg [-3.69315/43.1733] Declination (J2000)
69- 74 F6.4 --- z [0.35/0.99] Redshift
76- 81 F6.2 mag BMAG [-22.54/-16.33] Absolute B-band magnitude
83- 87 F5.2 mag e_BMAG [0.03/30] Error in BMAG
89- 93 F5.2 kpc re [0.31/17.2] Half-light radius
95- 98 F4.2 kpc e_re [0.01/3.49] Error in re
100 A1 --- f_re [HW] Flag on re (1)
102 A1 --- l_sigma [<] Limit flag on sigma
104-106 I3 km/s sigma [10/190]? Velocity dispersion
108-109 I2 km/s e_sigma [1/92]? Error in sigma
111-115 F5.1 10+9Msun M [0.2/255.1]? Dynamical Mass
117-120 F4.1 10+9Msun e_M [0/38.7]? Error in M
122-126 F5.2 Msun/yr SFR[OII] [0.01/16.47]? Star formation rate from
[OII]λ3727
128-131 F4.1 Msun/yr e_SFR[OII] [0/11]? Error in SFR[OII]
133-137 F5.2 Msun/yr SFR(IR) [0.77/27.45]? Star formation rate from the
Spitzer 24µm flux
139-141 F3.1 Msun/yr e_SFR(IR) [0.1/0.9]? Error in SFR(IR)
143-145 F3.1 [-] O/H [0.77/27.45]? Oxygene abundance, 12+log(O/H)
147-149 F3.1 [-] e_O/H [0/2]? Error in O/H
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Note (1): Flag on re, defined as follows:
H = from HST observations
W = from WIYN observations
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History:
From electronic version of the journal
(End) Marianne Brouty [CDS] 06-Oct-2017