J/ApJ/681/1163 Late-type galaxies in Chandra deep fields (Lehmer+, 2008)
Tracing the mass-dependent star formation history of late-type galaxies using
X-ray emission: results from the Chandra deep fields.
Lehmer B.D., Brandt W.N., Alexander D.M., Bell E.F., Hornschemeier A.E.,
McIntosh D.H., Bauer F.E., Gilli R., Mainieri V., Schneider D.P.,
Silverman J.D., Steffen A.T., Tozzi P., Wolf C.
<Astrophys. J., 681, 1163-1182 (2008)>
=2008ApJ...681.1163L 2008ApJ...681.1163L
ADC_Keywords: Active gal. nuclei ; X-ray sources ; Redshifts ; Photometry, HST
Keywords: cosmology: observations - galaxies: active - galaxies: general -
galaxies: spiral - stars: formation - surveys - X-rays: galaxies -
X-rays: general
Abstract:
We report on the X-ray evolution over the last ∼9Gyr of cosmic
history (i.e., since z=1.4) of late-type galaxy populations in the
Chandra Deep Field-North and Extended Chandra Deep Field-South (CDF-N
and E-CDF-S, respectively; jointly CDFs) survey fields. Our late-type
galaxy sample consists of 2568 galaxies, which were identified using
rest-frame optical colors and HST morphologies. We utilized X-ray
stacking analyses to investigate the X-ray emission from these
galaxies, emphasizing the contributions from normal galaxies that are
not dominated by active galactic nuclei (AGNs). Over this redshift
range, we find significant increases (factors of ∼5-10) in the
X-ray-to-optical mean luminosity ratio (LX/LB) and the
X-ray-to-stellar mass mean ratio (LX/M*) for galaxy populations
selected by LB and M*, respectively. When analyzing galaxy samples
selected via SFR, we find that the mean X-ray-to-SFR ratio (LX/SFR)
is consistent with being constant over the entire redshift range for
galaxies with SFR=1-100M☉/yr, thus demonstrating that X-ray
emission can be used as a robust indicator of star formation activity
out to z∼1.4. We find that the star formation activity (as traced by
X-ray luminosity) per unit stellar mass in a given redshift bin
increases with decreasing stellar mass over the redshift range
z=0.2-1, which is consistent with previous studies of how star
formation activity depends on stellar mass. Finally, we extend our
X-ray analyses to Lyman break galaxies at z∼3 and estimate that
LX/LB at z∼3 is similar to its value at z=1.4.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 139 225 X-ray detected late-type galaxies: source properties
table2.dat 182 44 Stacked late-type normal galaxies: mean properties
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See also:
B/chandra : The Chandra Archive Log (CXC, 1999-)
II/253 : Chandra Deep Field South: multi-colour data (Wolf+, 2008)
II/261 : GOODS initial results (Giavalisco+, 2004)
J/A+A/465/1099 : Redshift catalog of 691 objects in CDFS (Ravikumar+, 2007)
J/ApJ/660/167 : Spitzer AGN candidates in CDFN (Donley+, 2007)
J/A+A/454/423 : GOODS-South Field VLT/FORS2 redshifts. II. (Vanzella+, 2006)
J/A+A/449/951 : GOODS-MUSIC sample: multicolour catalog (Grazian+, 2006)
J/AJ/131/2373 : Extended Chandra Deep Field-South survey (Virani+, 2006)
J/A+A/451/457 : X-ray properties of AGN in CDFS (Tozzi+, 2006)
J/ApJS/161/21 : Extended Chandra Deep Field-South survey (Lehmer+, 2005)
J/A+A/437/883 : K20 survey: spectroscopic catalogue (Mignoli+, 2005)
J/A+A/434/53 : GOODS-South Field redshifts (Vanzella+, 2005)
J/ApJS/155/271 : Chandra Deep Field-South: Optical spectroscopy (Szokoly+,
2004)
J/AJ/127/3121 : TKRS catalog of GOODS-North Field (Wirth+, 2004)
J/AJ/126/539 : The Chandra Deep Fields North and South (Alexander+, 2003)
J/AJ/126/632 : UBVRIz'HK' photometry of 2Ms CDFN X-ray sources (Barger+,
2003)
J/A+A/428/1043 : Redshifts from VIMOS VLT Deep Survey (Le Fevre+, 2004)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 3 A3 --- --- [CXO]
4- 22 A19 --- CXO Chandra source name (JHHMMSS.ss+DDMMSS.s) (1)
24- 28 F5.2 mag zmag HST/ACS F850LP (z850 band) magnitude
30- 33 F4.2 --- z Redshift estimated from litterature
34 A1 --- f_z [SP] Redshift: Spectroscopic or Photometric
36- 40 F5.2 [Lsun] logB Log of B band luminosity
42- 46 F5.2 [Msun] logM Log of stellar mass
48 A1 --- l_SFR Limit flag on SFR
49- 54 F6.2 Msun/yr SFR Star-Formation Rate
56- 63 A8 --- Field Chandra detection field (2)
65- 68 I4 ks Exp Full band (0.5-8keV) effective exposure time
70 A1 --- l_logFF Limit flag on logFF
71- 76 F6.2 [mW/m2] logFF Log of Full band (0.5-8keV) flux
78 A1 --- l_logSF Limit flag on logSF
79- 84 F6.2 [mW/m2] logSF Log of Soft band (0.5-2keV) flux
86 A1 --- l_logHF Limit flag on logHF
87- 92 F6.2 [mW/m2] logHF Log of Hard band (2-8keV) flux
94 A1 --- l_logFL Limit flag on logFL
95- 99 F5.2 [10-7W] logFL Log of Full band (0.5-8keV) luminosity
101 A1 --- l_logSL Limit flag on logSL
102-106 F5.2 [10-7W] logSL Log of Soft band (0.5-2keV) luminosity
108 A1 --- l_logHL Limit flag on logHL
109-113 F5.2 [10-7W] logHL Log of Hard band (2-8keV) luminosity
115 A1 --- f_Gamma Limit or approximate flag on Gamma
116-120 F5.2 --- Gamma Effective photon index Γ
122 A1 --- l_logR Limit flag on log R
123-127 F5.2 [-] logR Log of 0.5-8keV to R band flux ratio
129 A1 --- AGN? [YN] AGN candidate?
131-139 A9 --- n_AGN? AGN criterion (3)
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Note (1): Sources are in Simbad.
Note (2): For E-CDF-S identifications, the associated field number (1 to 4)
indicates the Chandra pointing within which the source was detected
(see Lehmer et al., 2005, Cat. J/ApJS/161/21 for details).
Note (3): AGN candidates identified according criteria as follows:
1 = X-ray hardness to identify luminous obscured source;
2 = X-ray-to-optical flux ratio;
3 = X-ray-to-SFR correlation;
4 = Infrared and Radio properties;
5 = Optical spectroscopy.
See section 4.1 for further details.
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Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
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1- 16 A16 --- Type Physical property used to select stacked
sample (logLB, logM* or SFR)
18- 21 F4.2 --- z Mean redshift
23- 25 I3 --- Ngal Number of stacked galaxies
27- 28 I2 --- Nx Number of X-ray detected normal
stacked galaxies
30- 34 F5.1 ct Fnet Net 0.5-8keV band source counts
36- 40 F5.1 ct Snet Net 0.5-2keV band source counts
42- 46 F5.1 ct Hnet Net 2-8keV band source counts
48- 51 F4.1 --- FS/N The 0.5-8keV band signal-to-noise
53- 56 F4.1 --- SS/N The 0.5-2keV band signal-to-noise
58- 60 F3.1 --- HS/N The 2-8keV band signal-to-noise
62- 67 F6.2 [mW/m2] logFF Log of mean 0.5-8keV band flux
69- 74 F6.2 [mW/m2] logSF Log of mean 0.5-2keV band flux
76 A1 --- l_logHF Limit flag on logHF
77- 82 F6.2 [mW/m2] logHF Log of mean 2-8keV band flux
84 A1 --- l_Fgal Limit flag on Fgal
85- 88 F4.2 --- Fgal Fraction of mean 0.5-8keV band flux
from X-ray undetected galaxies
90 A1 --- l_Sgal Limit flag on Sgal
91- 94 F4.2 --- Sgal Fraction of mean 0.5-2keV band flux
from X-ray undetected galaxies
96 A1 --- l_Hgal Limit flag on Hgal
97-100 F4.2 --- Hgal ? Fraction of mean 2-8keV band flux
from X-ray undetected galaxies
102-106 F5.2 [10-7W] logFL Log of mean 0.5-8keV band
rest-frame luminosity
108-112 F5.2 [10-7W] logSL Log of mean 0.5-2keV band
rest-frame luminosity
114 A1 --- l_logHL Limit flag on logHL
115-119 F5.2 [10-7W] logHL Log of mean 2-8keV band
rest-frame luminosity
121 A1 --- l_Gamma Limit on Gamma
122-125 F4.2 --- Gamma Mean effective photon index Γ
127-131 F5.2 [-] logR Log of mean 0.5-8keV to R band flux ratio
133-137 F5.2 [Lsun] logB ? Log of mean B band luminosity
139-143 F5.2 [Msun] logM ? Log of mean stellar mass
145-148 F4.2 [Msun/yr] logSFR ? Log of mean star formation rate
150-154 F5.2 [10-7W/Lsun] logXB ? Log of mean X-ray to B band
luminosity ratio
156-160 F5.2 [10-7W/Msun] logXM ? Log of mean X-ray luminosity to
stellar mass ratio
162-166 F5.2 [10-7W/Msun/yr] logXSFR ? Log of mean X-ray luminosity to
star formation rate ratio
168-171 F4.2 --- Fagn Estimated Fraction of 0.5-8keV
luminosity attributed to AGNs
173-176 F4.2 --- Sagn Estimated Fraction of 0.5-2keV
luminosity attributed to AGNs
178 A1 --- l_Hagn Limit flag on Hagn
179-182 F4.2 --- Hagn Estimated Fraction of 2-8keV
luminosity attributed to AGNs
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History:
From electronic version of the journal
(End) Greg Schwarz [AAS], Emmanuelle Perret [CDS] 28-Oct-2010