J/A+A/641/A168 Sample of 31 dwarf and 18 Lyman-Break galaxies (Nanni+, 2020)
The gas, metal, and dust evolution in low-metallicity local and high-redshift
galaxies.
Nanni A., Burgarella D., Theule P., Cote B., Hirashita H.
<Astron. Astrophys. 641, A168 (2020)>
=2020A&A...641A.168N 2020A&A...641A.168N (SIMBAD/NED BibCode)
ADC_Keywords: Models ; Galaxies ; Interstellar medium
Keywords: galaxies: evolution - galaxies: dwarf - galaxies: high-redshift -
galaxies: ISM
Abstract:
The chemical enrichment in the interstellar medium (ISM) of galaxies
is regulated by several physical processes: star birth and death,
grain formation and destruction, and galactic inflows and outflows.
Understanding such processes and their relative importance is
essential to following galaxy evolution and the chemical enrichment
through the cosmic epochs, and to interpreting current and future
observations. Despite the importance of such topics, the contribution
of different stellar sources to the chemical enrichment of galaxies,
for example massive stars exploding as Type II supernovae (SNe) and
low-mass stars, as well as the mechanisms driving the evolution of
dust grains, such as for example grain growth in the ISM and
destruction by SN shocks, remain controversial from both observational
and theoretical viewpoints.
In this work, we revise the current description of metal and dust
evolution in the ISM of local low-metallicity dwarf galaxies and
develop a new description of Lyman-break galaxies (LBGs) which are
considered to be their high-redshift counterparts in terms of star
formation, stellar mass, and metallicity. Our goal is to reproduce the
observed properties of such galaxies, in particular (i) the peak in
dust mass over total stellar mass (sMdust) observed within a few
hundred million years; and (ii) the decrease in sMdust at a later
time.
We fitted spectral energy distribution (SED) of dwarf galaxies and
LBGs with the 'Code Investigating GALaxies Emission' (CIGALE), through
which the total stellar mass, dust mass, and star formation rate are
estimated. For some of the dwarf galaxies considered, the metal and
gas content are available from the literature. We computed different
prescriptions for metal and dust evolution in these systems (e.g.
different initial mass functions for stars, dust condensation
fractions, SN destruction, dust accretion in the ISM, and inflow and
outflow efficiency), and we fitted the properties of the observed
galaxies through the predictions of the models.
Only some combinations of models are able to reproduce the observed
trend and simultaneously fit the observed properties of the galaxies
considered. In particular, we show that (i) a top-heavy initial mass
function that favours the formation of massive stars and a dust
condensation fraction for Type II SNe of around 50% or more help to
reproduce the peak of sMdust observed after ∼100Myr from the beginning
of the baryon cycle for both dwarf galaxies and LBGs; (ii) galactic
outflows play a crucial role in reproducing the observed decline in
sMdust with age and are more efficient than grain destruction from
Type II SNe both in local galaxies and at high-redshift; (iii) a star
formation efficiency (mass of gas converted into stars) of a few
percent is required to explain the observed metallicity of local dwarf
galaxies; and (iv) dust growth in the ISM is not necessary in order to
reproduce the values of sMdust derived for the galaxies under study,
and, if present, the effect of this process would be erased by
galactic outflows.
Description:
Derived properties for the sample of dwarf local galaxies selected
from the "Dwarf Galaxy Survey" (DGS) (Madden et al.,
2013PASP..125..600M 2013PASP..125..600M, and Burgarella et al. 2020A&A...637A..32B 2020A&A...637A..32B for the
spectral distribution fitting and the selection) and Lyman-Break
galaxies between 5<z<10 (LBGs) (Burgarella et al.,
2020A&A...637A..32B 2020A&A...637A..32B) that have been individually fitted through the
chemical evolution models.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table3.dat 222 49 Physical properties of 31 DGS and 18 LBGs
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Byte-by-byte Description of file: table3.dat
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Bytes Format Units Label Explanations
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1- 12 A12 --- Name Name of the galaxy
14- 22 E9.4 --- chi2 Averaged residual given by Eq. 15
24- 32 E9.4 --- MSil Predicted mass of silicate dust normalised for
the final stellar mass (=1Msun at 13x109yr)
34- 42 E9.4 --- e_MSil Uncertainty of predicted mass of silicate dust
44- 52 E9.4 --- MCar Predicted mass of carbon dust normalised for
the final stellar mass (=1Msun at 13x109yr)
54- 62 E9.4 --- e_MCar Uncertainty of predicted mass of carbon dust
64- 72 E9.4 --- Miron Predicted mass of iron dust normalised for the
final stellar mass (=1 Msun at 13x109yr)
74- 82 E9.4 --- e_Miron Uncertainty of predicted mass of iron dust
84- 92 E9.4 --- fcond Dust condensation fraction for SNe II
94-102 E9.4 --- e_fcond Uncertainty on dust condensation fraction
for SNe II
104-112 E9.4 --- Mgas Initial mass of baryons normalised for
final stellar mass (=1Msun at 13x109yr)
114-122 E9.4 --- e_Mgas Uncertainty of initial mass of baryons
124-132 E9.4 --- alpha Slope of the top-heavy Initial Mass Function
in Eq. 3
134-142 E9.4 --- e_alpha Uncertainty of slope of the top-heavy IMF
144-150 E7.2 --- Mswept Mass of gas swept-up by a SN event in Eq. 8
152-158 E7.2 --- e_Mswept Uncertainty of Mswept
160-168 E9.4 --- fdustout Fraction of circumgalactic dust over the total
170-178 E9.4 --- e_fdustout Uncertainty of circumgalactic dust over
the total
180-188 E9.4 --- fgasout Fraction of circumgalactic gas over the total
190-198 E9.4 --- e_fgasout Uncertainty of circumgalactic gas over
the total
200-208 E9.4 --- fdoutSN Ratio between dust ejected by the galactic
outflow and total ejected and destroyed
by SN shocks
210-218 E9.4 --- e_fdoutSN Uncertainty of ratio between the dust ejected
by galactic outflow and total ejected and
destroyed by SN shocks
220-222 A3 --- Type Type of galaxy (DGS or LBG)
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Acknowledgements:
Ambra Nanni, ambra.nanni(at)lam.fr
(End) Ambra Nanni [LAM, France], Patricia Vannier [CDS] 30-Jul-2020