NASA/IPAC EXTRAGALACTIC DATABASE
Date and Time of the Query: 2019-05-22 T08:25:52 PDT
Help | Comment | NED Home

For refcode 1994PASJ...46..147S:
Retrieve 2 NED objects in this reference.
Please click here for ADS abstract

NED Abstract

Copyright by Astronomical Society of Japan. 1994PASJ...46..147S CO Observations of Edge-on Galaxies. IV. NGC 4565: Radial Variation of the H_2_-to-H I Ratio Yoshiaki SOFUE Institute of Astronomy, The University of Tokyo, Mitaka, Tokyo 181 E-mail: sofue@sof.mtk.ioa.s.u-tokyo.ac.jp and Naomasa NAKAI Nobeyama Radio Observatory, Minamimaki-mura, Minamisaku, Nagano 384-13 (Received 1992 August 10; accepted 1993 November 17) Abstract The edge-on galaxy NGC 4565 has been observed in the ^12^CO (J = 1-0)- line emission using the Nobeyama 45m telescope with an angular resolution of 15". We obtained a scan along the major axis for +/-5'(+/-15 kpc) about the galactic center, and some scans perpendicular to the galactic plane. The radial density distribution shows a dense molecular gas ring of 5 kpc radius, which is associated with an HI ring. The molecular disk comprises two components: an unresolved thin and dense disk, and a thick disk (or a halo) extending to a height greater than 1.4 kpc. The position-velocity diagram shows that the general rotation of the entire galaxy is circular with a flat rotation curve. However, the radial distribution of molecular gas is asymmetric with respect to the galaxy center in the sense that the molecular gas is much richer in the northwest side. We derived a radial variation of the H_2_-to-(HI+H_2_) density ratio, and found that interstellar gas in the central 4 kpc region is almost entirely H_2_, while HI is dominant beyond 10 kpc. A similar H I-vs-H_2_ behavior was found in the edge-on galaxy NGC 891. Key words: CO emission - Edge-on galaxies - Galaxies - Molecular hydrogen
Retrieve 2 NED objects in this reference.
Please click here for ADS abstract

Back to NED Home