The Herschel Virgo Cluster Survey III. A constraint on dust grain lifetime in early-type galaxies

M. S. Clemens , A. P. Jones , A. Bressan , M. Baes , G. J. Bendo , S. Bianchi , D. J. Bomans , A. Boselli (1) , E. Corbelli , L. Cortese , A. Dariush , J. I. Davies , I. de Looze , S. Di Serego Alighieri , D. Fadda , J. Fritz , D. A. Garcia-Appadoo , G. Gavazzi , C. Giovanardi , M. Grossi , T. M. Hughes , L. K. Hunt , S. Madden , D. Pierini , M. Pohlen , S. Sabatini , M. W. L. Smith , J. Verstappen , C. Vlahakis , E. M. Xilouris , S. Zibetti

1 LAM - Laboratoire d'Astrophysique de Marseille

Passive early-type galaxies (ETGs) provide an ideal laboratory for studying the interplay between dust formation around evolved stars and its subsequent destruction in a hot gas. Using Spitzer-IRS and Herschel data we compare the dust production rate in the envelopes of evolved AGB stars with a constraint on the total dust mass. Early-type galaxies which appear to be truly passively evolving are not detected by Herschel. We thus derive a distance independent upper limit to the dust grain survival time in the hostile environment of ETGs of \textless46 +/- 25 Myr for amorphous silicate grains. This implies that ETGs which are detected at far-infrared wavelengths have acquired a cool dusty medium via interaction. Given likely time-scales for ram-pressure stripping, this also implies that only galaxies with dust in a cool (atomic) medium can release dust into the intra-cluster medium.

Domaines: Astrophysique [astro-ph]

M. S. Clemens, A. P. Jones, A. Bressan, M. Baes, G. J. Bendo, et al.. The Herschel Virgo Cluster Survey III. A constraint on dust grain lifetime in early-type galaxies. Astronomy and Astrophysics - A&A, 2010, 518, ⟨10.1051/0004-6361/201014533⟩. ⟨hal-01434465⟩