The absence of diffuse gas around the dwarf spheroidal galaxy Leo I

Details The absence of diffuse gas around the dwarf spheroidal galaxy Leo I The absence of diffuse gas around the dwarf spheroidal galaxy Leo I

1996-08-28

arxiv.org/abs/astro-ph/9608189v3

Astronomy and Astrophysics

Astrophysics

New version, re-submitted to Archive Oct-22-1996 with corrections to the mass estimate of gas around the galaxy. 20 pages plai

Scientific paper

10.1086/303823

We have obtained spectra of three QSO/AGNs with the GHRS aboard the Hubble Space Telescope to search for absorption from low column density gas in the halo of the dwarf spheroidal (dSph) galaxy Leo I. The probe sightlines pass 2.1, 3.7, and 8.1 kpc from the center of the galaxy, but no CIV, SiII, or SiIV absorption is found at the velocity of Leo I. The absence of low ionization species suggests that the column density of neutral hydrogen which exists within 2-4 kpc of the galaxy is N(HI) < 10^{17} cm^{-2}; assuming that the high ionization lines of SiIV and CIV dominate the ionization fraction of silicon and carbon, the limit to the total hydrogen column is N(H) < 10^{18} cm^{-2}. Our results demonstrate that there are no dense flows of gas in or out of Leo I, and that there is no evidence for tidally disrupted gas which might have accompanied the galaxy's formation or evolution. However, our detection limits are insufficient to rule out the existence of a sphere or shell of ionized gas around the dSph, with a mass up to that constituting the entire galaxy. Our models show that dSph galaxies similar to Leo I are not massive enough to have halos which can contribute significantly to the metal line absorption cross-section of QSO absorbers seen at high redshift.

Affiliated with

Also associated with

No associations

Rating

The absence of diffuse gas around the dwarf spheroidal galaxy Leo I 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 The absence of diffuse gas around the dwarf spheroidal galaxy Leo I, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and The absence of diffuse gas around the dwarf spheroidal galaxy Leo I will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-696775