A Herschel-ATLAS study of dusty spheroids: probing the minor-merger process in the local Universe

Autor: Chris Lintott, Loretta Dunne, Sugata Kaviraj, Michał J. Michałowski, David L. Clements, Robbie Richard Auld, R. Hopwood, Simon P. Driver, Yuan-Sen Ting, Daniel J. Smith, G. de Zotti, Antonio Cava, Nathan Bourne, A. Dariush, Edo Ibar, Stephen Anthony Eales, Elisabetta Valiante, Asantha Cooray, Maarten Baes, C. Hoyos, N. K. Agius, Martin Bureau, Anne E. Sansom, Kate Rowlands, Steve Maddox, Stanislav S. Shabala, Mehmet Alpaslan, Matthew Smith
Jazyk: angličtina
Rok vydání: 2013
Předmět:
Cosmology and Nongalactic Astrophysics (astro-ph.CO)
formation [galaxies]
Stellar mass
INFRARED-EMISSION
DATA RELEASE
FOS: Physical sciences
F500
Astrophysics
Astrophysics::Cosmology and Extragalactic Astrophysics
01 natural sciences
cD
Luminosity
ELLIPTIC GALAXIES
0103 physical sciences
EARLY-TYPE GALAXIES
SIMPLE-MODEL
Astrophysics::Solar and Stellar Astrophysics
010303 astronomy & astrophysics
evolution [galaxies]
Astrophysics::Galaxy Astrophysics
Physics
ISM [galaxies]
interactions [galaxies]
RECENT STAR-FORMATION
DIGITAL-SKY-SURVEY
010308 nuclear & particles physics
Star formation
Astronomy
Astronomy and Astrophysics
Mass ratio
Galaxy
Dust lane
Interstellar medium
Physics and Astronomy
Space and Planetary Science
Stellar mass loss
MASS ASSEMBLY GAMA
ZOO DUST
Astrophysics::Earth and Planetary Astrophysics
SCIENCE DEMONSTRATION PHASE
elliptical and lenticular [galaxies]
Astrophysics - Cosmology and Nongalactic Astrophysics
Zdroj: \mnras
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
2013MNRAS.435.1463K
ISSN: 0035-8711
Popis: We use multi-wavelength (0.12 - 500 micron) photometry from Herschel-ATLAS, WISE, UKIDSS, SDSS and GALEX, to study 23 nearby spheroidal galaxies with prominent dust lanes (DLSGs). DLSGs are considered to be remnants of recent minor mergers, making them ideal laboratories for studying both the interstellar medium (ISM) of spheroids and minor-merger-driven star formation in the nearby Universe. The DLSGs exhibit star formation rates (SFRs) between 0.01 and 10 MSun yr^-1, with a median of 0.26 MSun yr^-1 (a factor of 3.5 greater than the average SG). The median dust mass, dust-to-stellar mass ratio and dust temperature in these galaxies are around 10^7.6 MSun yr^-1, ~0.05% and ~19.5 K respectively. The dust masses are at least a factor of 50 greater than that expected from stellar mass loss and, like the SFRs, show no correlation with galaxy luminosity, suggesting that both the ISM and the star formation have external drivers. Adopting literature gas-to-dust ratios and star formation histories derived from fits to the panchromatic photometry, we estimate that the median current and initial gas-to-stellar mass ratios in these systems are ~4% and ~7% respectively. If, as indicated by recent work, minor mergers that drive star formation in spheroids with (NUV-r)>3.8 (the colour range of our DLSGs) have stellar mass ratios between 1:6 and 1:10, then the satellite gas fractions are likely >50%.
MNRAS in press
Databáze: OpenAIRE
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