2014MNRAS.438L..66M

We present the results of an analysis of archival 21cm (Hi) data of the blue compact dwarf galaxy Haro 11 (ESO 350-IG038). Observations were obtained at the Very Large Array, and the presence of a compact absorption feature near the optical centre of the galaxy has been detected. The central location of the absorption feature coincides with the centre of the continuum background of the galaxy, as well as with the location of knot B. The absorption feature yields an Hi mass in the range of 3-10 x10⁸ M_☉, corresponding to spin temperatures from 91K to 200K, respectively. The absence of Hi seen in emission places an upper limit of 1.7x10⁹ M_☉ on the mass. To our knowledge this is the first example of a dwarf galaxy that shows Hi absorption from its own background continuum. The continuum emission from the galaxy is also used to determine star formation rates, namely 6.85±0.05M_☉/yr(for a stellar mass range of 5M_☉ < M < 100M_☉), or 32.8±0.2M_☉/yr (for an extended range of 0.1M_☉ < M < 100M_☉).