Testing CDM predictions with a deep HI survey of the Sculptor group



As a consequence of the cold dark matter (CDM) paradigm, galaxies arethought to form and evolve in a continuous process of mergers andaccretion of dark-matter haloes. Some of the predictions resulting fromthis scenario include the presence of hundreds of satellites in galaxiesgroups like our Local Group as well as the presence of a "cosmic web" ofdark matter and gas that interconnects galaxies, groups, and clusters.To put the predictions of the CDM paradigm to the test, we propose tomap the northern part of the nearby Sculptor group in the 21-cm HIemission down to an extremely low HI column density level of about1.4×10^17 cm^-2, using the multi-beam system at Parkes. The aimsof the observations are to directly detect and study the cosmic web andto create a complete census of gaseous galaxies and satellites with M_HI>~ 10^6 M_sun to investigate the "missing satellites" problem. Thesurvey data will be complemented with archival data at UV, optical, andIR wavelengths as well as existing, deep ATCA HI data of the majorSculptor group galaxies.
Date made available1 Apr 2013
PublisherSAO/NASA Astrophysics Data System (ADS)

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