Astronomy and Astrophysics – Astrophysics – Galaxy Astrophysics
Scientific paper
2010-03-03
Astronomy and Astrophysics
Astrophysics
Galaxy Astrophysics
6 pages, 3 figures. Accepted for publication in Astronomy & Astrophysics
Scientific paper
AIMS. In this work we explore the possibility of using the fast expansion of a Type Ia supernova photosphere to detect extra-galactic ISM column density variations on spatial scales of ~100 AU on time scales of a few months. METHODS. We constructed a simple model which describes the expansion of the photodisk and the effects of a patchy interstellar cloud on the observed equivalent width of Na I D lines. Using this model we derived the behavior of the equivalent width as a function of time, spatial scale and amplitude of the column density fluctuations. RESULTS. The calculations show that isolated, small (<100 AU) clouds with Na I column densities exceeding a few 10^11 cm^-2 would be easily detected. In contrast, the effects of a more realistic, patchy ISM become measurable in a fraction of cases, and for peak-to-peak variations larger than ~10^12 cm^-2 on a scale of 1000 AU. CONCLUSIONS. The proposed technique provides a unique way to probe the extra-galactic small scale structure, which is out of reach for any of the methods used so far. The same tool can also be applied to study the sub-AU Galactic ISM structure.
Branch David
Cox Nick L. J.
Parrent Jerod
Patat Ferdinando
No associations
LandOfFree
Studying the small scale ISM structure with supernovae 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 Studying the small scale ISM structure with supernovae, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Studying the small scale ISM structure with supernovae will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-684464