J/A+A/647/A76 Disc galaxies baryonic specific ang. mom. (Mancera Pina+, 2021)
The baryonic specific angular momentum of disc galaxies.
Mancera Pina, P.E., Posti L., Fraternali F., Adams E.A.K., Oosterloo T.
<Astron. Astrophys. 647, A76 (2021)>
=2021A&A...647A..76M 2021A&A...647A..76M (SIMBAD/NED BibCode)
ADC_Keywords: Galaxies ; Morphology
Keywords: galaxies: kinematics and dynamics - galaxies: formation -
galaxies: fundamental parameters - galaxies: evolution -
galaxies: dwarfs - galaxies: spirals
Abstract:
Specific angular momentum (the angular momentum per unit mass, j=J/M)
is one of the key parameters that control the evolution of galaxies,
and it is closely related with the coupling between dark and visible
matter. In this work, we aim to derive the baryonic (stars plus atomic
gas) specific angular momentum of disc galaxies and study its relation
with the dark matter specific angular momentum.
Using a combination of high-quality HI rotation curves, HI surface
densities, and near-infrared surface brightness profiles, we
homogeneously measure the stellar (j*) and gas (jgas) specific
angular momenta for a large sample of nearby disc galaxies. This
allows us to determine the baryonic specific angular momentum (jbar)
with high accuracy and across a very wide range of masses.
We confirm that the j*-M* relation is an unbroken power-law from
7≲log(M*/M☉)≲11.5, with a slope 0.54±0.02, setting a
stronger constraint at dwarf galaxy scales than previous
determinations. Concerning the gas component, we find that the
jgas-Mgas relation is also an unbroken power-law from
6≲log(Mgas/M☉)≲11, with a steeper slope of 1.01±0.04.
Regarding the baryonic relation, our data support a correlation
characterized by a single power-law with a slope 0.58±0.02. Our
analysis shows that our most massive spirals and smallest dwarfs lie
along the same jbar-Mbar sequence. While the relations are tight and
unbroken, we find internal correlations inside them: At fixed M,
galaxies with larger j have larger disc scale lengths, and at fixed
Mbar, gas-poor galaxies have lower jbar than expected. We estimate the
retained fraction of baryonic specific angular momentum, fjbar,
finding it constant across our entire mass range with a value of 0.7,
indicating that the baryonic specific angular momentum of present-day
disc galaxies is comparable to the initial specific angular momentum
of their dark matter haloes. In general, these results set important
constraints for hydrodynamical simulations and semi-analytical models
that aim to reproduce galaxies with realistic specific angular
momenta.
Description:
Stellar, gas and baryonic (stars+gas) specific angular momenta and
mass for a sample of 157 disc galaxies. The optical disc scale length
of each galaxy is also provided, together with a so-called convergence
factor on the specific angular momentum cumulative profile. See main
paper for further details.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
tbsam.dat 136 157 Main catalogue (updated table, 16-Jul-2021)
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Byte-by-byte Description of file: tbsam.dat
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Bytes Format Units Label Explanations
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1- 9 A9 --- Name Galaxy name
12- 20 E9.2 Msun Mstar Stellar mass
21- 29 E9.2 Msun e_Mstar Uncertainty in Mstar
30- 38 E9.2 Msun Mgas Gas mass
39- 47 E9.2 Msun e_Mgas Uncertainty in Mgas
48- 56 E9.2 Msun Mbar Baryonic mass
57- 65 E9.2 Msun e_Mbar Uncertainty in Mbar
67- 72 F6.1 kpc*km/s jstar ?=- Stellar specific angular momentum
75- 80 F6.1 kpc*km/s e_jstar ?=- Uncertainty in jstar
82- 88 F7.1 kpc*km/s jgas Gas specific angular momentum
91- 96 F6.1 kpc*km/s e_jgas Uncertainty in jgas
99-104 F6.1 kpc*km/s jbar ?=- Baryonic specific angular momentum
107-113 F7.2 kpc*km/s e_jbar ?=- Uncertainty in jbar
115-118 F4.2 kpc Rd Optical exponential disc scale length
121-124 F4.2 --- rstar ?=- Convergence factor in jstar
127-130 F4.2 --- rgas Convergence factor in jgas
133-136 F4.2 --- rbar ?=- Convergence factor in jbar
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Acknowledgements:
Pavel E. Mancera Pina, pavel(at)astro.rug.nl
History:
10-Mar-2021: on-line version
16-Jul-2021: corrected table (from author)
(End) Pavel Mancera Pina [Univ. Groningen], Patricia Vannier [CDS] 08-Jan-2021