J/MNRAS/448/3484 ATLAS3D Project. XXX (McDermid+, 2015)
The ATLAS3D Project.
XXX. Star formation histories and stellar population scaling relations of
early-type galaxies.
McDermid R.M., Alatalo K., Blitz L., Bournaud F., Bureau M., Cappellari M.,
Crocker A.F., Davies R.L., Davis T.A., De Zeeuw P.T., Duc P.-A.,
Emsellem E., Khochfar S., Krajnovic D., Kuntschner H., Morganti R.,
Naab T., Oosterloo T., Sarzi M., Scott N., Serra P., Weijmans A.-M.,
Young L.M.
<Mon. Not. R. Astron. Soc., 448, 3484-3513 (2015)>
=2015MNRAS.448.3484M 2015MNRAS.448.3484M (SIMBAD/NED BibCode)
ADC_Keywords: Galaxy catalogs ; Abundances
Keywords: galaxies: abundances - galaxies: elliptical and lenticular, cD -
galaxies: evolution - galaxies: stellar content
Abstract:
We present the stellar population content of early-type galaxies from
the ATLAS3D survey. Using spectra integrated within apertures covering
up to one effective radius, we apply two methods: one based on
measuring line-strength indices and applying single stellar population
(SSP) models to derive SSP-equivalent values of stellar age,
metallicity, and alpha enhancement; and one based on spectral fitting
to derive non-parametric star formation histories, mass-weighted
average values of age, metallicity, and half-mass formation
time-scales. Using homogeneously derived effective radii and
dynamically determined galaxy masses, we present the distribution of
stellar population parameters on the Mass Plane (MJAM, σe,
Rmaje), showing that at fixed mass, compact early-type galaxies
are on average older, more metal-rich, and more alpha-enhanced than
their larger counterparts. From non-parametric star formation
histories, we find that the duration of star formation is
systematically more extended in lower mass objects. Assuming that our
sample represents most of the stellar content of today's local
Universe, approximately 50 percent of all stars formed within the
first 2Gyr following the big bang. Most of these stars reside today in
the most massive galaxies (>1010.5M☉), which themselves formed
90 percent of their stars by z∼2. The lower mass objects, in contrast,
have formed barely half their stars in this time interval. Stellar
population properties are independent of environment over two orders
of magnitude in local density, varying only with galaxy mass. In the
highest density regions of our volume (dominated by the Virgo
cluster), galaxies are older, alpha-enhanced, and have shorter star
formation histories with respect to lower density regions.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table4.dat 43 260 Mass-weighted stellar population properties
measured within Re
table1.dat 86 260 Measured Lick index measurements and SSP
parameters measured within Re/8
table2.dat 86 260 Measured Lick index measurements and SSP
parameters measured within Re/2
table3.dat 86 260 Measured Lick index measurements and SSP
parameters measured within Re
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See also:
J/MNRAS/413/813 : ATLAS3D project. I (Cappellari+, 2011)
J/MNRAS/414/888 : ATLAS3D project. III (Emsellem+, 2011)
J/MNRAS/414/940 : ATLAS3D project. IV (Young+, 2011)
J/MNRAS/416/1680 : ATLAS3D project. VII (Cappellari+, 2011)
J/MNRAS/433/2812 : ATLAS3D project. XXIII (Krajnovic+, 2013)
J/MNRAS/446/120 : ATLAS3D project. XXIX (Duc+, 2015)
Byte-by-byte Description of file: table4.dat
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Bytes Format Units Label Explanations
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1- 10 A10 --- Name Galaxy name
12- 16 F5.2 Gyr Age Mass-weighted age
18- 21 F4.2 Gyr e_Age rms uncertainty on Age
23- 27 F5.2 [-] [Z/H] Mass-weighted metallicity
29- 32 F4.2 [-] e_[Z/H] rms uncertainty on [Z/H]
34- 38 F5.2 Gyr t50 Half-mass formation time
40- 43 F4.2 Gyr e_t50 rms uncertainty on t50
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Byte-by-byte Description of file: table1.dat table2.dat table3.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 10 A10 --- Name Galaxy name
12- 15 F4.2 0.1nm Hbeta Hbeta Lick index measurements within
Re/8, Re/2 or Re (1)
17- 20 F4.2 0.1nm e_Hbeta rms uncertainty on Hbeta
22- 26 F5.2 0.1nm Fe5015 Fe5015 Lick index measurements within
Re/8, Re/2 or Re (1)
28- 31 F4.2 0.1nm e_Fe5015 rms uncertainty on Fe5015
33- 36 F4.2 0.1nm Mgb Mgb Lick index measurements within
Re/8, Re/2 or Re (1)
38- 41 F4.2 0.1nm e_Mgb rms uncertainty on Mgb
43- 46 F4.2 0.1nm Fe5270 ?=- Fe5270 Lick index measurements within
Re/8, Re/2 or Re (1)
48- 51 F4.2 0.1nm e_Fe5270 ?=- rms uncertainty on Fe5270
53- 57 F5.2 Gyr Age ?=- Estimates of SSP-equivalent age (2)
59- 62 F4.2 Gyr e_Age ?=- rms uncertainty on Age
64- 68 F5.2 [-] [Z/H] ?=- Estimates of SSP-equivalent
metallicity (2)
70- 73 F4.2 [-] e_[Z/H] ?=- rms uncertainty on [Z/H]
75- 79 F5.2 [-] [a/Fe] ?=- Estimates of SSP-equivalent
abundance ratio (2)
81- 84 F4.2 [-] e_[a/Fe] ?=- rms uncertainty on [a/Fe]
86 I1 --- Qual [1/4] Quality flag (3)
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Note (1): measured on the Lick/IDS system
Note (2): Estimates of SSP-equivalent age, metallicity and abundance ratio
within a circular aperture of radius Re/8, Re/2 or Re, using the SSP models
of Schiavon (2007) and using the three indices Hbeta, Fe5015, and Mgb.
Note (3): Quality flag:
1 = Data are of good quality
2 = Object with weak Fe5015 index in the Re/8, Re/2 or Re aperture
3 = Strong emission line residuals
4 = low signal-to-noise ratio
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History:
From electronic version of the journal
References:
Cappellari et al., Paper I 2011MNRAS.413..813C 2011MNRAS.413..813C, Cat. J/MNRAS/413/813
Krajnovic et al., Paper II 2011MNRAS.414.2923K 2011MNRAS.414.2923K
Emsellem et al., Paper III 2011MNRAS.414..888E 2011MNRAS.414..888E, Cat. J/MNRAS/414/888
Young et al., Paper IV 2011MNRAS.414..940Y 2011MNRAS.414..940Y, Cat. J/MNRAS/414/940
Davis et al., Paper V 2011MNRAS.414..968D 2011MNRAS.414..968D
Bois et al., Paper VI 2011MNRAS.416.1654B 2011MNRAS.416.1654B
Cappellari et al., Paper VII 2011MNRAS.416.1680C 2011MNRAS.416.1680C, Cat. J/MNRAS/416/1680
Khochfar et al., Paper VIII 2011MNRAS.417..845K 2011MNRAS.417..845K
Duc et al., Paper IX 2011MNRAS.417..863D 2011MNRAS.417..863D
Davis et al., Paper X 2011MNRAS.417..882D 2011MNRAS.417..882D
Crocker et al., Paper XI 2012MNRAS.421.1298C 2012MNRAS.421.1298C
Lablanche et al., Paper XII 2012MNRAS.424.1495L 2012MNRAS.424.1495L
Serra et al., Paper XIII 2012MNRAS.422.1835S 2012MNRAS.422.1835S
Krajnovic et al., Paper XIV 2013MNRAS.432.1768K 2013MNRAS.432.1768K
Cappellari et al., Paper XV 2013MNRAS.432.1709C 2013MNRAS.432.1709C
Bayet et al., Paper XVI 2013MNRAS.432.1742B 2013MNRAS.432.1742B
Krajnovic et al., Paper XVII 2013MNRAS.432.1768K 2013MNRAS.432.1768K
Alatalo et al., Paper XVIII 2013MNRAS.432.1796A 2013MNRAS.432.1796A
Sarzi et al., Paper XIX 2013MNRAS.432.1845S 2013MNRAS.432.1845S
Cappellari et al., Paper XX 2013MNRAS.432.1862C 2013MNRAS.432.1862C
Scott et al., Paper XXI 2013MNRAS.432.1894S 2013MNRAS.432.1894S
Martig et al., Paper XXII 2013MNRAS.432.1914M 2013MNRAS.432.1914M
Krajnovic et al., Paper XXIII 2013MNRAS.433.2812K 2013MNRAS.433.2812K, Cat. J/MNRAS/433/2812
Davis et al., Paper XXIV 2013MNRAS.429..534D 2013MNRAS.429..534D
Cappellari et al., Paper XXV 2013MNRAS.432.1709C 2013MNRAS.432.1709C
Bayet et al., Paper XXVI 2013MNRAS.432.1742B 2013MNRAS.432.1742B
Krajnovic et al., Paper XXVII 2013MNRAS.432.1768K 2013MNRAS.432.1768K
Alatalo et al., Paper XXVIII 2013MNRAS.432.1796A 2013MNRAS.432.1796A
Duc et al., Paper XXIX 2015MNRAS.446..120D 2015MNRAS.446..120D
(End) Patricia Vannier [CDS] 15-Sep-2015