The Herschel exploitation of local galaxy Andromeda (HELGA) - V. Strengthening the case for substantial interstellar grain growth

Mattsson, LarsKTH,Stockholms universitet,Nordiska institutet för teoretisk fysik (Nordita),University of Copenhagen, Denmark,Nordic Institute for Theoretical Physics NORDITA,Stockholm University, Sweden (författare)

AuthorCount:10;
QC 20141114
In this paper, we consider the implications of the distributions of dust and metals in the disc of M31. We derive mean radial dust distributions using a dust map created from Herschel images of M31 sampling the entire far-infrared peak. Modified blackbodies are fit to approximately 4000 pixels with a varying, as well as a fixed, dust emissivity index (beta). An overall metal distribution is also derived using data collected from the literature. We use a simple analytical model of the evolution of the dust in a galaxy with dust contributed by stellar sources and interstellar grain growth, and fit this model to the radial dust-to-metals distribution across the galaxy. Our analysis shows that the dust-to-gas gradient in M31 is steeper than the metallicity gradient, suggesting interstellar dust growth is (or has been) important in M31. We argue that M31 helps build a case for cosmic dust in galaxies being the result of substantial interstellar grain growth, while the net dust production from stars may be limited. We note, however, that the efficiency of dust production in stars, e.g. in supernovae ejecta and/or stellar atmospheres, and grain destruction in the interstellar medium may be degenerate in our simple model. We can conclude that interstellar grain growth by accretion is likely at least as important as stellar dust production channels in building the cosmic dust component in M31.

NATURVETENSKAP Fysik Astronomi, astrofysik och kosmologi hsv//swe
NATURAL SCIENCES Physical Sciences Astronomy, Astrophysics and Cosmology hsv//eng
ISM: clouds
dust
extinction
ISM: evolution
galaxies: evolution
galaxies: individual: M31
galaxies: ISM

Gomez, H. L. (författare)
Andersen, A. C. (författare)
Smith, M. W. L. (författare)
De Looze, I. (författare)
Baes, M. (författare)
Viaene, S. (författare)
Gentile, G. (författare)
Fritz, J. (författare)
Spinoglio, L. (författare)
Stockholms universitetNordiska institutet för teoretisk fysik (Nordita) (creator_code:org_t)

Ingår i:Monthly notices of the Royal Astronomical Society: Oxford University Press (OUP)444:1, s. 797-8070035-87111365-2966

Av författaren/redakt...: Mattsson, Lars; Gomez, H. L.; Andersen, A. C.; Smith, M. W. L.; De Looze, I.; Baes, M.; visa fler...; Viaene, S.; Gentile, G.; Fritz, J.; Spinoglio, L.; visa färre...

Om ämnet

Kungliga biblioteket hanterar dina personuppgifter i enlighet med EU:s dataskyddsförordning (2018), GDPR. Läs mer om hur det funkar här.
Så här hanterar KB dina uppgifter vid användning av denna tjänst.