II ZWICKY 23 AND FAMILY: A GROUP IN INTERACTION
2016
ASTRONOMICAL JOURNAL
DOI
10.3847/0004-6256/152/3/69
II Zw 23 (UGC 3179) is a luminous (M-B similar to -21) nearby compact narrow emission line starburst galaxy with blue optical colors and strong emission lines. We present a photometric and morphological study of II Zw 23 and its interacting companion, KPG103a, using data obtained with the WIYN 3.5m telescope in combination with a WFPC2 image from the Hubble Space Telescope archives. II Zw 23 has a highly disturbed outer structure with long trails of debris that may be contributing material toward the production of tidal dwarfs. Its central regions appear disky, a structure that is consistent with the overall rotation pattern observed in the Ha velocity field measured from Densepak observations obtained with WIYN. We find additional evidence for interaction in this system, including the discovery of a new tidal loop extending from an associated dwarf galaxy, which appears to be in the process of disrupting along its orbit. We also present Ha equivalent widths and discuss the relative star formation rates across this interacting system.