J/MNRAS/456/790 TP-AGB stars contribution in SFR (Capozzi+, 2016)
Revisiting the role of the thermally pulsating asymptotic-giant-branch phase
in high-redshift galaxies.
Capozzi D., Maraston C., Daddi E., Renzini A., Strazzullo V., Gobat R.
<Mon. Not. R. Astron. Soc., 456, 790-830 (2016)>
=2016MNRAS.456..790C 2016MNRAS.456..790C (SIMBAD/NED BibCode)
ADC_Keywords: Models ; Stars, horizontal branch ; Energy distributions
Keywords: stars: AGB and post-AGB - galaxies: evolution - galaxies: formation -
galaxies: high-redshift
Abstract:
We study the debated contribution from thermally pulsing
asymptotic-giant-branch (TP-AGB) stars in evolutionary population
synthesis models. We investigate the spectral energy distributions
(SEDs) of a sample of 51 spectroscopically confirmed, high-z
(1.3<zspec<2.7), galaxies using three evolutionary population
synthesis models with strong, mild and light TP-AGB. Our sample is the
largest of spectroscopically confirmed galaxies on which such models
are tested so far. Galaxies were selected as passive, but we model
them using a variety of star formation histories in order not to be
dependent on this pre-selection. We find that the observed SEDs are
best fitted with a significant contribution of TP-AGB stars or with
substantial dust attenuation. Without including reddening,
TP-AGB-strong models perform better and deliver solutions consistent
within 1σ from the best-fitted ones in the vast majority of
cases. Including reddening, all models perform similarly. Using
independent constraints from observations in the mid- and far-IR, we
show that low/negligible dust attenuation, i.e. E(B-V)≲0.05, should
be preferred for the SEDs of passively selected galaxies. Given that
TP-AGB-light models give systematically older ages for passive
galaxies, we suggest number counts of passive galaxies at higher
redshifts as a further test to discriminate among stellar population
models.
Description:
We carry out SED fitting on the observed SEDs following the same
method adopted in Maraston et al. (2006ApJ...652...85M 2006ApJ...652...85M, M06).
In order to be able to make a direct comparison with the results shown
in Maraston et al. (2006ApJ...652...85M 2006ApJ...652...85M), we keep the template setup
identical. This is made of 32 sets of theoretical model spectra
covering a broad range of SFHs: (i) SSP (simple stellar population,
i.e. single starburst); (ii) exponentially declining SFR (star
formation rate; τ-model with τ=0.1, 0.3 and 1Gyr); (iii)
truncated SFR (step-like star formation, i.e. constant for a time
interval Δt=0.1, 0.3 and 1Gyr since galaxy formation, null
afterwards); (iv) constant SFR. Each SFH option is calculated for four
metallicities (1/5, 1/2, 1 and 2 Z☉).
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 212 7 Observed photometry for the HUDF sample in AB
magnitudes
tableb1.dat 55 132 *SED-fitting results for the COSMOS sample using
the full-filter-set and the original photometry:
no-reddening case
tableb2.dat 68 132 *SED-fitting results for the COSMOS sample using
the full-filter-set and the original photometry:
reddening case
tableb3.dat 74 102 *SED-fitting solutions obtained after excluding
possibly physically unreliable solutions for
both HUDF and COSMOS, using the full-filter
set and the original photometry in presence of
reddening
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Note on tableb*.dat: Values refer to the best-fitting solution.
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Byte-by-byte Description of file: table1.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 5 I5 --- NID New identification number
7- 10 F4.2 --- zsp Spectroscopic redshift
12 A1 --- l_Ucmag Upper Limit at 1σ level flag on Ucmag
13- 17 F5.2 mag Ucmag CTIO U magnitude (AB)
19- 22 F4.2 mag e_Ucmag ? rms uncertainty on CTIO U magnitude
23 A1 --- l_Uvmag Upper Limit at 1σ level flag on Uvmag
24- 28 F5.2 mag Uvmag VIMOS U magnitude (AB)
30- 33 F4.2 mag e_Uvmag ? rms uncertainty on CVIMOS U magnitude
35- 39 F5.2 mag F435W HST F435W magnitude (AB)
41- 44 F4.2 mag e_F435W rms uncertainty on F435W
46- 50 F5.2 mag F606W HST F606W magnitude (AB)
52- 55 F4.2 mag e_F606W rms uncertainty on F606W
57- 62 F6.3 mag F775W HST F775W magnitude (AB)
64- 68 F5.3 mag e_F775W rms uncertainty on F775W
70- 74 F5.2 mag F814W HST F814W magnitude (AB)
76- 79 F4.2 mag e_F814W rms uncertainty on F814W
81- 86 F6.3 mag F850LP HST F850LP magnitude (AB)
88- 92 F5.3 mag e_F850LP rms uncertainty on F850LP
94- 99 F6.3 mag F105W HST F105W magnitude (AB)
101-105 F5.3 mag e_F105W rms uncertainty on F105W
107-110 I4 --- UDF UDF identification number from
Maraston et al. (2006ApJ...652...85M 2006ApJ...652...85M)
112-117 F6.3 mag F125W HST F125W magnitude (AB)
119-123 F5.3 mag e_F125W rms uncertainty on F125W
125-130 F6.3 mag F160W HST F160W magnitude (AB)
132-136 F5.3 mag e_F160W rms uncertainty on F160W
138-143 F6.3 mag Ksimag ISAAC Ks magnitude (AB)
145-149 F5.3 mag e_Ksimag rms uncertainty on Ksimag
151-156 F6.3 mag Kshmag HAWK-I Ks magnitude (AB)
158-162 F5.3 mag e_Kshmag rms uncertainty on HAWK-I Ks magnitude
164-169 F6.3 mag [3.6] IRAC 3.6um magnitude (AB)
171-175 F5.3 mag e_[3.6] rms uncertainty on [3.6]
177-182 F6.3 mag [4.5] IRAC 4.5um magnitude (AB)
184-188 F5.3 mag e_[4.5] rms uncertainty on [4.5]
190-195 F6.3 mag [5.8] IRAC 5.8um magnitude (AB)
197-201 F5.3 mag e_[5.8] rms uncertainty on [5.8]
203-207 F5.2 mag [8.0] IRAC 8.0um magnitude (AB)
209-212 F4.2 mag e_[8.0] rms uncertainty on [8.0]
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Byte-by-byte Description of file: tableb1.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 2 I2 --- ID [1/44] Galaxy ID
4- 9 F6.4 --- zsp Spectroscopic redshift
11- 14 A4 --- Model Model
16- 19 F4.2 Gyr t Age
21- 23 F3.1 [Sun] [Z/H] Metallicity
25- 40 A16 --- SFH Star formation history
42- 45 F4.2 --- chi2r Reduced chi2
47- 50 F4.2 10+11Msun M* Stellar mass
52 A1 --- l_SFR Limit flag on SFR
53- 55 F3.1 Msun/yr SFR Star formation rate
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Byte-by-byte Description of file: tableb2.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 2 I2 --- ID [1/44] Galaxy ID
4- 9 F6.4 --- zsp Spectroscopic redshift
11- 14 A4 --- Model Model
16- 19 F4.2 Gyr t Age
21- 23 F3.1 [Sun] [Z/H] Metallicity
25- 40 A16 --- SFH Star formation history
41- 44 F4.2 --- chi2r Reduced chi2
46- 49 F4.2 10+11Msun M* Stellar mass
51 A1 --- l_SFR Limit flag on SFR
52- 54 F3.1 Msun/yr SFR Star formation rate
56- 59 F4.2 mag E(B-V) Reddening
61- 68 A8 --- rlaw Reddenning law (G1)
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Byte-by-byte Description of file: tableb3.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 5 I5 --- ID Galaxy ID
7- 12 F6.4 --- zsp Spectroscopic redshift
14- 17 A4 --- Model Model
19- 22 F4.2 Gyr t Age
24- 26 F3.1 [Sun] [Z/H] Metallicity
28- 43 A16 --- SFH Star formation history
47- 50 F4.2 --- chi2r Reduced chi2
52- 55 F4.2 10+11Msun M* Stellar mass
57 A1 --- l_SFR Limit flag on SFR
58- 60 F3.1 Msun/yr SFR Star formation rate
62- 65 F4.2 mag E(B-V) Reddening
67- 74 A8 --- rlaw Reddenning law (G1)
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Global notes:
Note (G1): References as follows:
A76 = Allen (1976MNRAS.174p..29A 1976MNRAS.174p..29A)
C00 = Calzetti et al. (2000ApJ...533..682C 2000ApJ...533..682C)
F86 = Fitzpatrick (1986AJ.....92.1068F 1986AJ.....92.1068F)
P84 = Prevot et al. (1984A&A...132..389P 1984A&A...132..389P)
B85 = Bouchet et al. (1985A&A...149..330B 1985A&A...149..330B)
S79 = Seaton (1979MNRAS.187p..73S 1979MNRAS.187p..73S)
NA = The SED of this galaxy was best-fitted with E(B-V)=0 also when
reddening was allowed.
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History:
From electronic version of the journal
(End) Patricia Vannier [CDS] 02-Aug-2016