J/MNRAS/468/305 Galaxy chemical evolution models (Molla+, 2017)
Galaxy chemical evolution models: the role of molecular gas formation.
Molla M., Diaz A.I., Ascasibar Y., Gibson B.K.
<Mon. Not. R. Astron. Soc., 468, 305-318 (2017)>
=2017MNRAS.468..305M 2017MNRAS.468..305M (SIMBAD/NED BibCode)
ADC_Keywords: Abundances ; Models, evolutionary ; Galaxies
Keywords: ISM: molecules - Galaxy: abundances - galaxies: star formation
Abstract:
In our classical grid of multiphase chemical evolution models, star
formation in the disc occurs in two steps: first, molecular gas forms,
and then stars are created by cloud-cloud collisions or interactions
of massive stars with the surrounding molecular clouds. The formation
of both molecular clouds and stars are treated through the use of free
parameters we refer to as efficiencies. In this work, we modify the
formation of molecular clouds based on several new prescriptions
existing in the literature, and we compare the results obtained for a
chemical evolution model of the Milky Way Galaxy regarding the
evolution of the Solar region, the radial structure of the Galactic
disc and the ratio between the diffuse and molecular components, H
I/H2. Our results show that the six prescriptions we have tested
reproduce fairly consistent most of the observed trends, differing
mostly in their predictions for the (poorly constrained) outskirts of
the Milky Way and the evolution in time of its radial structure. Among
them, the model proposed by Ascasibar et al. (in preparation), where
the conversion of diffuse gas into molecular clouds depends on the
local stellar and gas densities as well as on the gas metallicity,
seems to provide the best overall match to the observed data.
Description:
We present the catalogue with the time evolution of the six computed
models of the publication. We also give as electronic table the
results corresponding to the effective radius obtained for each model
of the six shown in this work.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
catalog.dat 197 208350 *Time evolution results for the six models
presented in the work.
rhalf.dat 110 1389 Evolution of the effective radius for total mass
and half stellar radius with the half stellar
mass for each one of the six models
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Note on catalog.dat: There are 1389 time steps from 0 to 13.2Gyr,
25 radial regions from R=0 to 24 kpc and 6 models.
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Byte-by-byte Description of file: catalog.dat
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Bytes Format Units Label Explanations
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1- 3 A3 --- Model Model: BLI, GNE, KRU, MOD, STD, ASC
7- 17 E11.5 Gyr Time 1389 evolutionary time steps from 0 to 13.2Gyr
22- 24 F3.0 kpc R Galactocentric radius for 25 regions
from R=0 to 24kpc
26- 32 F7.3 kpc+2 Area Area for the considered region
34- 42 E9.3 Msun/yr SFR Star formation rate of each region in each time
44- 49 F6.2 Msun/pc2 Sig-t Surface density of the total mass involved in
the model
51- 56 F6.2 Msun/pc2 Sig-d Surface density of the total mass in the disc
58- 63 F6.2 Msun/pc2 Sig-HI Surface density of the diffuse gas
65- 70 F6.2 Msun/pc2 Sig-H2 Surface density of the molecular gas
72- 77 F6.2 Msun/pc2 Sig-S2 Surface density of massive stars
79- 84 F6.2 Msun/pc2 Sig-S1 Surface density of low-mass stars
86- 91 F6.2 Msun/pc2 Sig-rem Surface density of remnants
93- 98 F6.3 --- H Abundance of H in mass
101-109 E9.3 --- D Abundance of D in mass
112-120 E9.3 --- He3 Abundance of 3He in mass
123-127 F5.3 --- He4 Abundance of 4He in mass
130-134 F5.2 --- C12 Abundance of 12C in mass
137-141 F5.2 --- C13 Abundance of 13C in mass
144-148 F5.2 --- N14 Abundance of 14N in mass
151-155 F5.2 --- O Abundance of O in mass
157-162 F6.2 --- Ne Abundance of Ne in mass
164-169 F6.2 --- Mg Abundance of Mg in mass
171-176 F6.2 --- Si Abundance of Si in mass
178-183 F6.2 --- S Abundance of S in mass
185-190 F6.2 --- Ca Abundance of Ca in mass
192-197 F6.2 --- Fe Abundance of Fe in mass
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Byte-by-byte Description of file: rhalf.dat
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Bytes Format Units Label Explanations
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1- 6 F6.3 Gyr Time Evolutionary time (1389 steps)
9- 14 F6.3 kpc R1/2M Half mass radius for disk mass
17- 22 F6.3 kpc R1/2SB Half stellar mass radius for BLI
24- 30 F7.3 [Msun] logM1/2B logarithm of the half stellar mass for BLI
33- 38 F6.3 kpc R1/2G Half stellar mass radius for GNE
40- 46 F7.3 [Msun] logM1/2G logarithm of the half stellar mass for GNE
49- 54 F6.3 kpc R1/2K Half stellar mass radius for KRU
56- 62 F7.3 [Msun] logM1/2K logarithm of the half stellar mass for KRU
65- 70 F6.3 kpc R1/2SM Half stellar mass radius for MOD
72- 78 F7.3 [Msun] logM1/2M logarithm of the half stellar mass for MOD
81- 86 F6.3 kpc R1/2S Half stellar mass radius for STD
88- 94 F7.3 [Msun] logM1/2S logarithm of the half stellar mass for STD
97-102 F6.3 kpc R1/2A Half stellar mass radius for ASC
104-110 F7.3 [Msun] logM1/2A logarithm of the half stellar mass for ASC
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Acknowledgements:
Mercedes Molla, mercedes.molla(at)hotmail.es
(End) Patricia Vannier [CDS] 22-Oct-2021