Letter to the Editor

The Herschel Virgo Cluster Survey^*

III. A constraint on dust grain lifetime in early-type galaxies

¹ INAF-Osservatorio Astronomico di Padova, Vicolo dell'Osservatorio 5, 35122 Padova, Italy e-mail: marcel.clemens@oapd.inaf.it
² Institut d'Astrophysique Spatiale (IAS), Bâtiment 121, Université Paris-Sud 11 and CNRS, 91405 Orsay, France e-mail: Anthony.Jones@ias.u-psud.fr
³ SISSA-ISAS, International School for Advanced Studies, via Beirut 4, 34014 Trieste, Italy
⁴ Sterrenkundig Observatorium, Universiteit Gent, Krijgslaan 281 S9, 9000 Gent, Belgium
⁵ Astrophysics Group, Imperial College London, Blackett Laboratory, Prince Consort Road, London SW7 2AZ, UK
⁶ INAF-Osservatorio Astrofisico di Arcetri, Largo Enrico Fermi 5, 50125 Firenze, Italy
⁷ Astronomical Institute, Ruhr-University Bochum, Universitaetsstr. 150, 44780 Bochum, Germany
⁸ Laboratoire d'Astrophysique de Marseille, UMR 6110 CNRS, 38 rue F. Joliot-Curie, 13388 Marseille, France
⁹ Department of Physics and Astronomy, Cardiff University, The Parade, Cardiff, CF24 3AA, UK
¹⁰ NASA Herschel Science Center, California Institute of Technology, MS 100-22, Pasadena, CA 91125, USA
¹¹ ESO, Alonso de Cordova 3107, Vitacura, Santiago, Chile
¹² Università di Milano-Bicocca, piazza della Scienza 3, 20100, Milano, Italy
¹³ CAAUL, Observatório Astronómico de Lisboa, Universidade de Lisboa, Tapada da Ajuda, 1349-018, Lisboa, Portugal
¹⁴ Laboratoire AIM, CEA/DSM – CNRS – Université Paris Diderot, Irfu/Service d'Astrophysique, 91191 Gif sur Yvette, France
¹⁵ Max-Planck-Institut fuer extraterrestrische Physik, Giessenbachstrasse, Postfach 1312, 85741, Garching, Germany
¹⁶ INAF-Istituto di Astrofisica Spaziale e Fisica Cosmica, via Fosso del Cavaliere 100, 00133, Roma, Italy
¹⁷ Leiden Observatory, Leiden University, PO Box 9513, 2300 RA Leiden, The Netherlands
¹⁸ National Observatory of Athens, I. Metaxa and Vas. Pavlou, P. Penteli, 15236 Athens, Greece
¹⁹ Max-Planck-Institut fuer Astronomie, Koenigstuhl 17, 69117 Heidelberg, Germany

Received: 29 March 2010
Accepted: 30 April 2010

Abstract

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 <46±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.