The Local Volume HI Survey

ESO 121-G020 and ATCA J061608-574552 (HIPASS J0615-57) are a close dwarf galaxy pair, separated by ~3 arcmin. Karachentsev et al. (2006) obtain a TRGB distance of 6.05 ± 0.49 Mpc for ESO121-G020. The HIPASS detection includes HI emission from ESO 121-G020 (v_sys = 584 km/s) and its dwarf galaxy companion ATCA J061608-574552 (v_sys = 540 km/s), which was discovered by Warren et al. (2006). No other companions are known within at least 5 degrees. Our ATCA HI maps show two regularly rotating galaxies. We measure F_HI = 7.3 Jy km/s for ESO 121-G020 and 2.1 Jy km/s for the companion. Assuming the above distance for both we derive M_HI = 6.3 and 1.8 × 10⁷ M_☉, respectively. Warren et al. (2006) obtain HI mass to light ratios of ~1.5 and ~2.2 M_☉/L_☉. Both galaxies are clearly detected in GALEX UV images. For a detailed analysis of ESO 121-G020's HI kinematics see Kirby et al. (2012).

Reference: Koribalski et al. 2018 * LVHIS database * LVHIS homepage * next