2001/05/07 by L. S. Pilyugin · 2 citations
Physics and Astronomy · #Abundance (ecology) #Astronomy and Astrophysical Research #Astrophysics and Star Formation Studies #Dispersion (optics) #Galaxies: Formation, Evolution, Phenomena #Galaxy #Oxygen #RADIUS #Spiral galaxy #astro-ph
paper · pdf · doi:10.1051/0004-6361:20010598
7 pages, 5 figures, accepted for publication in Astronomy and Astrophysics
arxiv created 2001/05/07 · openalex publication_date 2001/07/01 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
The well-observed spiral galaxy M 101 was considered. The radial distributions of oxygen abundances determined in three different ways (with the classic Te-method, with the R23-method, and with the P-method) were compared. It was found that the parameters (the central oxygen abundance and the gradient) of the radial (O/H)P abundance distribution are close to those of the (O/H) abundance distribution. The parameters of the (O/H) abundance distribution differ significantly from those of the (O/H) abundance distribution: the central (O/H) oxygen abundance is higher by around 0.4 dex and the gradient is steeper by a factor of around 1.5 as compared to those values in the (O/H) abundance distribution. The dispersion in (O/H)P abundance at fixed radius is rather small, ~0.08 dex, and is equal to that in (O/H) abundance. The dispersion in (O/H) abundance at fixed radius is appreciably larger, ~0.16 dex, compared to that in (O/H) abundance. It has been shown that the extra dispersion in (O/H) abundances is an artifact and reflects scatter in excitation parameter P at fixed radius.