Astronomy and Astrophysics – Astrophysics
Scientific paper
1998-07-25
Astronomy and Astrophysics
Astrophysics
LaTeX, 23 pages including 4 figures. To appear in ApJ (Main Journal)
Scientific paper
10.1086/306654
The H II region created by the progenitor of SN 1987A was further heated and ionized by the supernova flash. Prior to the flash, the temperature of the gas was 4000 - 5000 K, and helium was neutral, while the post-flash temperature was only slightly less than 10^5 K, with the gas being ionized to helium-like ionization stages of C, N and O. We have followed the slow post-flash cooling and recombination of the gas, as well as its line emission, and find that the strongest lines are N V 1240 and O VI 1034. Both these lines are good probes for the density of the gas, and suitable instruments to detect the lines are STIS on HST and FUSE, respectively. Other lines which may be detectable are N IV] 1486 and [O III] 5007, though they are expected to be substantially weaker. The relative strength of the oxygen lines is found to be a good tracer of the color temperature of the supernova flash. From previous observations, we put limits on the hydrogen density, n_H, of the H II region. The early N V 1240 flux measured by IUE gives an upper limit which is n_H ~ 180 \eta^{-0.40} cm^{-3}, where \eta is the filling factor of the gas. The recently reported emission in [O III] 5007 at 2500 days requires n_H = (160\pm12) \eta^{-0.19} cm^{-3}, for a supernova burst similar to that in the 500full1 model of Ensman & Burrows (1992). For the more energetic 500full2 burst the density is n_H = (215\pm15) \eta^{-0.19} cm^{-3}. These values are much higher than in models of the X-ray emission from the supernova (n_H ~ 75 cm^{-3}), and it seems plausible that the observed [O III] emission is produced primarily elsewhere than in the H II region. We also discuss the type of progenitor consistent with the H II region. In particular, it seems unlikely that its spectral type was much earlier than B2 Ia.
No associations
LandOfFree
Flash ionization of the partially ionized wind of the progenitor of SN 1987A 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 Flash ionization of the partially ionized wind of the progenitor of SN 1987A, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Flash ionization of the partially ionized wind of the progenitor of SN 1987A will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-130494