Na I D Lines in the SN 2002ap Spectrum
Abstract
High-dispersion, high-S/N spectroscopic observations of SN2002ap in M74 were carried out in the wavelength range of 4120-6860Å using the High Dispersion Spectrograph of the Subaru Telescope. Neither emission nor absorption features relating to SN2002ap itself were identified in the high-dispersion echelle spectrum, but a pair of Na I D1 and D2 absorption lines were detected at a redshift corresponding to the disk of M74, and each was found to show three components. The column densities of these components are log N(Na I) = 11.47, 10.47, and 10.72 for the first, second, and third components, respectively. The interstellar reddening in M74 was estimated from these components, and was combined with that in the Galaxy to yield a total value of E(B-V) = 0.09 ± 0.01 along the line of sight to SN2002ap.
- Publication:
-
Publications of the Astronomical Society of Japan
- Pub Date:
- December 2002
- DOI:
- 10.1093/pasj/54.6.899
- Bibcode:
- 2002PASJ...54..899T
- Keywords:
-
- galaxies: individual (M 74);
- ISM: atoms;
- supernovae: individual (SN 2002ap)