Deep optical imaging of the dark galaxy candidate AGESVC1282

0535352 - ASÚ 2021 RIV FR eng J - Journal Article
Bílek, M. - Mueller, O. - Vudragovic, A. - Taylor, Rhys
Deep optical imaging of the dark galaxy candidate AGESVC1282.
Astronomy & Astrophysics. Roč. 642, October (2020), č. článku L10. ISSN 0004-6361. E-ISSN 1432-0746
R&D Projects: GA MŠMT(CZ) LM2015067; GA ČR(CZ) GA19-18647S
Institutional support: RVO:67985815
Keywords : galaxies * formation * image processing
OECD category: Astronomy (including astrophysics,space science)
Impact factor: 5.803, year: 2020
Method of publishing: Open access

The blind HI survey Arecibo Galaxy Environment Survey (AGES) detected several unresolved sources in the Virgo cluster, which do not have optical counterparts in the Sloan Digital Sky Survey. The origin of these dark clouds is unknown. They might be crucial objects since they could be the so-called dark galaxies, that is, the dark matter halos without stellar content that are expected from cosmological simulations. In order to reveal the nature of the dark clouds, we took a deep optical image of one them, AGESVC1 282, with the newly-commissioned 1.4 m Milankovi Telescope. After observing it for 10.4 h in the L-filter, the image reached a surface-brightness limit of about 29.1 mag arcsec(-2) in V. No optical counterpart was detected. We placed an upper limit on the V-band luminosity of the object of 1.1x10(7) L-circle dot, giving a stellar mass below 1.4x10(7) M-circle dot and a HI-to-stellar mass ratio above 3.1. By inspecting archival HI observations of the surrounding region, we found that none of the standard explanations for optically dark HI clouds fits the available constraints on this object.
Permanent Link: http://hdl.handle.net/11104/0313396