J/ApJS/193/30 UV-to-FIR analysis of sources in the EGS. II. (Barro+, 2011)
UV-to-FIR analysis of Spitzer/IRAC sources in the Extended Groth Strip.
II. Photometric redshifts, stellar masses, and star formation rates.
Barro G., Perez-Gonzalez P.G., Gallego J., Ashby M.L.N., Kajisawa M.,
Miyazaki S., Villar V., Yamada T., Zamorano J.
<Astrophys. J. Suppl. Ser., 193, 30 (2011)>
=2011ApJS..193...30B 2011ApJS..193...30B
ADC_Keywords: Redshifts ; Galaxies, IR ; Models
Keywords: galaxies: high-redshift - galaxies: photometry - galaxies: starburst -
infrared: galaxies
Abstract:
Based on the ultraviolet to far-infrared photometry already compiled
and presented in a companion paper (Barro et al. 2011, Cat.
J/ApJS/193/13), we present a detailed spectral energy distribution
(SED) analysis of nearly 80000 IRAC 3.6+4.5um selected galaxies in the
Extended Groth Strip. We estimate photometric redshifts, stellar
masses, and star formation rates (SFRs) separately for each galaxy in
this large sample. The catalog includes 76936 sources with
[3.6]≤23.75 (85% completeness level of the IRAC survey) over
0.48deg2. The typical photometric redshift accuracy is
Δz/(1+z)=0.034, with a catastrophic outlier fraction of just 2%.
We quantify the systematics introduced by the use of different stellar
population synthesis libraries and initial mass functions in the
calculation of stellar masses. We find systematic offsets ranging from
0.1 to 0.4dex, with a typical scatter of 0.3dex. We also provide UV-
and IR-based SFRs for all sample galaxies, based on several sets of
dust emission templates and SFR indicators. We evaluate the systematic
differences and goodness of the different SFR estimations using the
deep FIDEL 70um data available in the Extended Groth Strip. Typical
random uncertainties of the IR-bases SFRs are a factor of two, with
non-negligible systematic effects at z≳1.5 observed when only MIPS
24um data are available.
Description:
The present work is based on the multi-wavelength catalog of IRAC
3.6+4.5um selected galaxies in the EGS (RA=14h14m, DEC=+53°30')
presented in Paper I (Barro et al. 2011, Cat. J/ApJS/193/13). We
cross-correlated our IRAC-selected catalog with the X-ray (Chandra)
and radio (VLA/20cm) catalogs of Laird et al. (2009, Cat.
J/ApJS/180/102) and Ivison et al. (2007ApJ...660L..77I 2007ApJ...660L..77I), and with all
the spectroscopic redshifts from DEEP2 DR3 and a small sample of 238
spectroscopically confirmed Lyman break galaxies (LBGs) from Steidel
et al. (2003, Cat. J/ApJ/592/728).
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table7.dat 87 76936 The IRAC-3.6+4.5um sample: Photometric redshifts
table8.dat 139 76936 The IRAC-3.6+4.5um sample: stellar mass estimates
table9.dat 169 76936 The IRAC-3.6+4.5um sample: IR-luminosities and
star formation rate estimates
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See also:
J/ApJS/193/13 : Spitzer/IRAC sources in the EGS I. SEDs (Barro+, 2011)
J/A+A/526/A72 : Early-type galaxies in the EGS (Fernandez Lorenzo+, 2011)
J/ApJS/180/102 : AEGIS-X: Chandra deep survey (Laird+, 2009)
J/ApJ/675/234 : Stellar mass functions for galaxies 0<z<4 (Perez-Gonzalez+,
2008)
J/ApJS/177/431 : Mid-IR sources in EGS (Barmby+, 2008)
J/AJ/132/2159 : IRAC counterparts of 6cm galaxies in EGS (Willner+, 2006)
J/ApJ/592/728 : Lyman break galaxies at redshift z∼3 (Steidel+, 2003)
http://irsa.ipac.caltech.edu/data/SPITZER/FIDEL/ : FIDEL data online
http://deep.berkeley.edu/DR3/dr3.primer.html : DEEP2 DR3 data products
Byte-by-byte Description of file: table7.dat
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Bytes Format Units Label Explanations
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1- 4 A4 --- --- [irac]
5- 12 A8 --- [BPG2011] Unique object identifier
14- 25 F12.8 deg RAdeg Right Ascension in decimal degrees (J2000)
27- 37 F11.8 deg DEdeg Declination in decimal degrees (J2000)
39- 43 F5.2 --- zph Probability weighted photometric redshift (1)
45- 50 F6.2 --- zEAZY ?=-99 EAZY photometric redshift (2)
52- 57 F6.2 --- zI06 ?=-99 Ilbert et al. (2006A&A...457..841I 2006A&A...457..841I)
photometric redshift (3)
59- 65 F7.5 --- zsp ?=0.00000 Spectroscopic redshift (4)
67 I1 --- q_zsp [0/4] Quality flag on zsp, 4=best (5)
69- 72 F4.2 --- e_zph Uncertainty in photometric redshift zph
74- 82 F9.2 --- q_zEAZY ?=-99 Reliability parameter for ZEAZY (6)
84- 85 I2 --- o_zph Number of different bands used to derive zph
with Rainbow software
87 I1 --- St Sum of the stellarity criteria satisfied (7)
--------------------------------------------------------------------------------
Note (1): This is our default value of photometric redshift for SED fitting
based estimates.
Note (2): With the code EAZY (Brammer et al. 2008ApJ...686.1503B 2008ApJ...686.1503B) using the
default template configuration and the K-band luminosity prior applied
to the [3.6] band. The input photometric catalog is the same as for
the other redshifts.
Note (3): From the (5-band) i' selected catalog of the CFHTLS. This catalog
overlaps with the IRAC sample in the central portion of the mosaic
(52.16°<δ<53.20° & 214.04°<α<215.74°).
Note (4): Determination drawn from DEEP2 (Davis et al. 2007ApJ...660L...1D 2007ApJ...660L...1D;
∼8000 galaxies) and (Steidel et al. 2003, Cat. J/ApJ/592/728; LBGs at
z≳3).
Note (5): Only redshifts with q_zsp>2 have been used in the analysis.
Quality code as follows:
4 = > 99.5%;
3 = > 90%;
2 = uncertain;
1 = bad quality.
0 = no spectroscopic redshift
Note (6): Estimated from the 1σ width of the probability distribution
function.
Note (7): See Section 5.4 of Paper I (Barro et al. Cat. J/ApJS/193/13).
A source is classified as star for Stellarity >2.
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Byte-by-byte Description of file: table8.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 4 A4 --- --- [irac]
5- 12 A8 --- [BPG2011] Unique object identifier
14- 25 F12.8 deg RAdeg Right Ascension in decimal degrees (J2000)
27- 37 F11.8 deg DEdeg Declination in decimal degrees (J2000)
39- 43 F5.2 [Msun] Mass Log of stellar mass using zbest (8)
45- 49 F5.2 [Msun] Mzsp Log of stellar mass using zspec (9)
51- 55 F5.2 [Msun] zM Redshift used in mass fitting procedures (10)
57- 61 F5.2 [Msun] MP01-K Log of P01,KROU stellar mass (11)
63- 67 F5.2 [Msun] MBC03-C Log of BC03,CHAB stellar mass (11)
69- 73 F5.2 [Msun] MM05-K Log of M05,KROU stellar mass (11)
75- 79 F5.2 [Msun] MCB09-C Log of CB09,CHAB stellar mass (11)
81- 85 F5.2 [Msun] MCB09-S Log of CB09,SALP stellar mass (11)
87- 91 F5.2 [Msun] MP01-C Log of P01,CF00 stellar mass (11)
93- 97 F5.2 [Msun] e_Mass Uncertainty in Mass
99-103 F5.2 [Msun] e_Mzsp Uncertainty in Mzsp
105-109 F5.2 [Msun] e_MP01-K Uncertainty in MP01-K
111-115 F5.2 [Msun] e_MBC03-C Uncertainty in MBC03-C
117-121 F5.2 [Msun] e_MM05-K Uncertainty in MM05-K
123-127 F5.2 [Msun] e_MCB09-C Uncertainty in MCB09-C
129-133 F5.2 [Msun] e_MCB09-S Uncertainty in MCB09-S
135-139 F5.2 [Msun] e_MP01-C Uncertainty in MP01-C
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Note (8): Estimated with our default modeling parameters, [P01,SALP,CAL01],
and zphot-best.
Note (9): Estimated with our default modeling parameters, [P01,SALP,CAL01],
forcing the photometric redshift to the spectroscopic value, when
available.
Note (10): Used in the fitting procedure of columns MP01-K through MP01-C.
This redshift refer to zphot-best unless the spectroscopic redshift is
available; in that case the redshift is forced to the spectroscopic value.
Note (11): Where P01, BC03, M05, and CB09 are the PEGASE 2.0, Fioc &
Rocca-Volmerange (P01, 1997A&A...326..950F 1997A&A...326..950F), Bruzual & Charlot
(2003MNRAS.344.1000B 2003MNRAS.344.1000B), Maraston (2005MNRAS.362..799M 2005MNRAS.362..799M), and Charlot &
Bruzual (CB09, 2011, in preparation) stellar population synthesis
models, respectively. SALP, KROU and CHAB are the Salpeter
(1955ApJ...121..161S 1955ApJ...121..161S), Kroupa (2001MNRAS.322..231K 2001MNRAS.322..231K), and Chabrier
(2003PASP..115..763C 2003PASP..115..763C) IMF laws, respectively, CAL01 is the extinction
law of Calzetti et al. (2000ApJ...533..682C 2000ApJ...533..682C), CF00 is the Charlot &
Fall (2000ApJ...539..718C 2000ApJ...539..718C) dust extinction law.
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Byte-by-byte Description of file: table9.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 4 A4 --- --- [irac]
5- 12 A8 --- [BPG2011] Unique object identifier
14- 25 F12.8 deg RAdeg Right Ascension in decimal degrees (J2000)
27- 37 F11.8 deg DEdeg Declination in decimal degrees (J2000)
39- 43 F5.2 --- zSF Redshift used in fitting procedure (10)
45- 49 I5 uJy F24 ? Spitzer/MIPS 24 micron band flux density
51- 53 I3 uJy e_F24 ? Uncertainty in F24
55- 60 I6 uJy F70 ? Spitzer/MIPS 70 micron band flux density
62- 66 I5 uJy e_F70 ? Uncertainty in F70
68- 76 F9.1 Msun/yr SFR0.28 UV based SFR from the monochromatic
luminosity at 2800Å (280nm) (12)
78- 86 F9.1 Msun/yr SFRR09 IR based SFR from MIPS 24um flux (13)
88- 93 F6.2 [Lsun] L24 Log of total IR luminosity (14)
95-102 F8.1 Msun/yr SFR24 SFR from L24 and Kennicutt 1998 calibration
104-111 F8.1 Msun/yr SFRCE01 SFR from L24 and CE01 models (15)
113-119 F7.1 Msun/yr SFRB08 SFR from L24 and B08 relation (16)
121-128 F8.1 Msun/yr SFRAH06 SFR from L24 and AH06 relation (17)
130-135 F6.2 [Lsun] Lb ? Log of total IR luminosity (18)
137-144 F8.1 Msun/yr SFRb ? SFR from Lb and Kennicutt
(1998ARA&A..36..189K 1998ARA&A..36..189K) calibration
146-153 F8.1 Msun/yr SFRCE01b ? SFR from Lb and CE01 models (15)
155-161 F7.1 Msun/yr SFRB08b ? SFR from Lb and B08 relationship (16)
163-169 F7.1 Msun/yr SFRAH06b ? SFR from Lband AH06 relation (17)
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Note (10): This redshift refer to zphot-best unless the spectroscopic
redshift is available; in that case the redshift is forced to the
spectroscopic value.
Note (12): Estimated from the monochromatic luminosity at 2800Å (280nm)
rest-frame using the calibration of Kennicutt (1998ARA&A..36..189K 1998ARA&A..36..189K).
We also refer to this value as SFRUV,obs.
Note (13): Estimated from the observed flux in MIPS 24 micron and the
redshift using the formula of Rieke et al. (2009, Cat. J/ApJ/692/556).
Note (14): Obtained integrating (from 8-1000 microns) the average of the
best fitting templates. Computed from the fit of MIPS 24 micron data
to the models of Chary & Elbaz (CE01, 2001ApJ...556..562C 2001ApJ...556..562C), Dale &
Helou (DH02, 2002ApJ...576..159D 2002ApJ...576..159D).
Note (15): In this case the IR SED is fitted only with the models of CE01
(Chary & Elbaz, 2001ApJ...556..562C 2001ApJ...556..562C).
Note (16): Estimated from the monochromatic luminosity at 8 micron
rest-frame using the relation of Bavouzet et al.
(2008A&A...479...83B 2008A&A...479...83B).
Note (17): Estimated from the monochromatic luminosity at 24 micron
rest-frame using the relation of Alonso-Herrero et al.
(2006ApJ...650..835A 2006ApJ...650..835A).
Note (18): Obtained integrating (from 8-1000 microns) the average of the
best fitting templates. Computed from the fit of IRAC-8.0 and MIPS 24
and 70 microns (best effort) data to the models of Chary & Elbaz
(CE01, 2001ApJ...556..562C 2001ApJ...556..562C) Dale & Helou (DH02, 2002ApJ...576..159D 2002ApJ...576..159D)
and Rieke et al. (2009, Cat. J/ApJ/692/556).
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History:
From electronic version of the journal
References:
Barro et al. Paper I. 2011ApJS..193...13B 2011ApJS..193...13B Cat. J/ApJS/193/13
(End) Greg Schwarz [AAS], Emmanuelle Perret [CDS] 27-May-2011