2001/03/02 by J. Vinko, J. Vinkó, L. L. Kiss +9 · 5 citations
Physics and Astronomy · #Astrophysical Phenomena and Observations #Gamma-ray bursts and supernovae #Stellar, planetary, and galactic studies #astro-ph
paper · pdf · doi:10.1086/321079
accepted for publication in Astron. Journal (2001 June)
arxiv created 2001/03/02 · openalex publication_date 2001/06/01 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/07/31
We present medium-resolution (λ/Δλ ≈ 2500) optical spectroscopy of SN 1999by in NGC 2841 made around its light maximum. That the depth ratio of the two Si II features at 5800 and 6150 Å are R (Si II) ≈ 0.63 at maximum indicates that this SN belongs to the peculiar subluminous Type SNe Ia. Radial velocities inferred from the minimum of the 6150 Å trough reveal a steeper decline of the velocity curve than expected for normal SNe Ia, consistent with the behavior of published VRI light curves. A revised absolute magnitude of SN 1999by and distance to its host galaxy NGC 2841 are estimated based on the multicolor light-curve shape (MLCS) method, resulting in M V (max) = -18.06 ± 0.1 mag and d = 17.1 ± 1.2 Mpc, respectively. An approximate linear dependence of the luminosity parameter Δ on R (Si II) is presented.