The Leo Triplet spiral galaxy NGC 3628. I - VLA observations of the neutral hydrogen absorption

Abstract

view Abstract Citations (26) References (19) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS The Leo Triplet Spiral Galaxy NGC 3628. I. VLA Observations of the Neutral Hydrogen Absorption Schmelz, J. T. ; Baan, W. A. ; Haschick, A. D. Abstract Hydrogen absorption is observed against the nuclear region of NGC 3628, an edge-on spiral galaxy in the Leo Triplet. VLA observations against the extended continuum reveal approximately 10 individual H I features which are resolved both spatially and in velocity space. A circular, rotating disk is identified as well as several lower velocity features which seem to form a second structure. This may be an expanding spiral arm, similar to the 3 kpc arm in the Galaxy, or a second disk which is either expanding with respect to the primary disk or elliptical in shape. All of the features are optically thick with tau roughly 1 in many cases.Estimated densities are high with n(HI+) greater than 100/cu cm and M roughly 100,000 solar masses for a typical feature. The high degree of activity in this galaxy, which includes complex hydroxyl absorption and H I extensions in the form of plumes and bridges, may have been triggered by a tidal encounter with NGC 3627, a second spiral in the triplet. Publication: The Astrophysical Journal Pub Date: April 1987 DOI: 10.1086/165154 Bibcode: 1987ApJ...315..492S Keywords: Absorption Spectra; Astronomical Spectroscopy; Hydrogen Clouds; Neutral Gases; Spiral Galaxies; Very Large Array (Vla); Astronomical Maps; Galactic Nuclei; Line Spectra; Nebulae; Radio Sources (Astronomy); Astrophysics; GALAXIES: INDIVIDUAL NGC NUMBER: NGC 3628; GALAXIES: INTERNAL MOTIONS; NEBULAE: H II REGIONS; RADIO SOURCES: 21 CM RADIATION full text sources ADS | data products SIMBAD (6) NED (4) Related Materials (1) Part 2: 1987ApJ...320..145S