Distribution and motions of H I in the SA galaxies NGC 1169 and NGC 3898

Details Distribution and motions of H I in the SA galaxies NGC 1169 and NGC 3898 Distribution and motions of H I in the SA galaxies NGC 1169 and NGC 3898

Jun 1994

adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=1994a%26a...286..395v&link_type=abstract

Astronomy and Astrophysics (ISSN 0004-6361), vol. 286, no. 2, p. 395-407

Astronomy and Astrophysics

Astronomy

9

Emission Spectra, Galactic Evolution, Hydrogen, Interstellar Matter, Line Spectra, Radio Astronomy, Radio Spectra, Spiral Galaxies, Decimeter Waves, Density (Mass/Volume), Ultrahigh Frequencies

Scientific paper

The Sa-type galaxies NGC 1169 and NGC 3898 were mapped in the 21-cm H I line at Westbrook with a spatial resolution of about 30 sec and a velocity resolution of 40 km/s. A comparison of the H I distributions of the 3 Sa galaxies mapped by us (NGC 1169 and 3898, and IC 5267) with those of 6 S0/a and RSB0/a, and 9 Sb-type spirals shows no clear difference between the mean H I surface density peak values of galaxies of types S0/a, Sa and Sb, and a distinct difference between the H I morphologies of barred and non-barred objects, the former showing pronounced central holes in their H I distributions. In all three Sa galaxies the H I surface density stays well below the threshold gas surface density for star formation, estimated with a simple model for disc stability against large-scale density perturbations. Even if we add the estimated H2 surface density in NGC 3898, which was detected in the CO(1-0) line, the total gas surface density probably stays below the threshold value everywhere in the galaxy. Therefore the wide-spread star formation presently occurring in Sa galaxies (though at a drastically reduced level compared to the past) must be due to local mechanisms, rather than no spontaneous large-scale gravitational collapse.

Affiliated with

Also associated with

No associations

Rating

Distribution and motions of H I in the SA galaxies NGC 1169 and NGC 3898 does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Distribution and motions of H I in the SA galaxies NGC 1169 and NGC 3898, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Distribution and motions of H I in the SA galaxies NGC 1169 and NGC 3898 will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-1862132