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Gas Rich Dwarfs from the PSS-II III. HI Profiles and Dynamical Masses

Jo Ann Eder·James Schombert
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Abstract

We present Arecibo neutral hydrogen data on a sample of optically selected dwarf galaxies. The sample ranges in HI mass from 10^6 M_sun to 5x10^9 M_sun, with a mean of 7.9x10^8 M_sun. Using estimated HI radii, the HI surface densities range from 0.6 to 20 M_sun pc^-2, all well below the critical threshold for star formation (Kennicutt 1998). M_HI/L values of the LSB dwarfs range from 0.3 to 12 with a mean value of 2.0. Dynamical masses, calculated from the HI profile widths, range from 10^8 M_sun to 10^11 M_sun. There is a strong correlation between optical luminosity and dynamical mass for LSB dwarfs implying that the dark matter (whether baryonic or non-baryonic) follows the detectable baryonic matter.

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Jo Ann Eder, James Schombert. 2000-06-21. Gas Rich Dwarfs from the PSS-II III. HI Profiles and Dynamical Masses. https://doi.org/10.1086/317357

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