Volume 380, Number 2, December III 2001
|Page(s)||409 - 417|
|Section||Cosmology (including clusters of galaxies)|
|Published online||15 December 2001|
Investigating the nature of the submillimeter selected galaxy SMM J02399-0136 with VLT spectropolarimetry*
European Southern Observatory, Karl Schwarzschild Str. 2, 85748 Garching bei München, Germany
2 Osservatorio Astrofisico di Arcetri, Largo E. Fermi, 50125 Firenze, Italy
Corresponding author: J. Vernet, firstname.lastname@example.org
Accepted: 18 September 2001
We present deep optical spectropolarimetry of SMM J02399-0136 () done with the VLT Antu 8.2 m telescope equipped with FORS1. Moderate continuum and emission line polarization are measured (). We do not detect broad lines in scattered flux as would be expected for a type-2 object but rather a polarization behaviour similar to BAL quasars. This classification is confirmed by the detection of both high and low ionization broad absorption troughs and a very red continuum. We argue that this object shares several properties with local ULIGs such as Mrk 231 and other ultraluminous infrared Lo-BAL quasars. However, the fact that the ultraviolet spectrum is dominated by non-stellar radiation does not prove that the dust that is thermally radiating in the far infrared is predominantly heated by the AGN. Since the energy that we get in the far-infrared is precisely that which is removed from the ultraviolet spectrum, this could mean that the starburst is more dust-enshrouded than the AGN due to a peculiar dust distribution. The limits we place on the putative starburst contribution to the restframe ultraviolet continuum together with constraints on the amount of extinction provide an upper limit to the star formation rate of about 2000 yr-1, consistent with previously claimed high star formation rates level in this object.
Key words: galaxies: active / galaxies: starburst / quasars: absorption lines / techniques: polarimetric / galaxies: individual: SMM J02399-0136
© ESO, 2001
Current usage metrics show cumulative count of Article Views (full-text article views including HTML views, PDF and ePub downloads, according to the available data) and Abstracts Views on Vision4Press platform.
Data correspond to usage on the plateform after 2015. The current usage metrics is available 48-96 hours after online publication and is updated daily on week days.
Initial download of the metrics may take a while.