|
| | | | |
| | | |
| Stat |
Members: 3645
Articles: 2'501'711
Articles rated: 2609
20 April 2024 |
|
| | | | |
|
Article overview
| |
|
|
The metallicity gradient of M 33: chemical abundances of HII regions | | L. Magrini
; J. M. Vilchez
; A. Mampaso
; R.L.M. Corradi
; P. Leisy
; | | Date: |
22 May 2007 | | Subject: | Astrophysics (astro-ph) | | Abstract: | We present spectroscopic observations of a sample of 72 emission-line
objects, including mainly HII regions, in the spiral galaxy M 33. Spectra were
obtained with the multi-object, wide field spectrograph AF2/WYFFOS at the 4.2m
WHT telescope. Line intensities, extinction, and electron density were
determined for the whole sample of objects. The aim of the present work was to
derive chemical and physical parameters of a set of HII regions, and from them
the metallicity gradient. Electron temperatures and chemical abundances were
derived for the 14 HII regions where both [OII] and [OIII] emission line fluxes
were measured, including the electron temperature sensitive emission line
[OIII] 436.3 nm and in a few cases [NII] 575.5 nm. The ionization correction
factor (ICF) method was used to derive the total chemical abundances. The
presence of abundance gradients was inferred from the radial behaviour of
several emission-line ratios, and accurately measured from chemical abundances
directly derived in 14 HII regions. The oxygen abundances of our HII regions,
located in the radial region from ~2 to ~7.2 kpc, gave an oxygen gradient
-0.054+/-0.011 dex/kpc The overall oxygen gradient for M 33 obtained using ours
and previous oxygen determinations in a large number of HII regions with direct
electron temperature determination as well as abundance in young stars
presented a two slope shape: -0.19 dex/kpc for the central regions (R<3kpc),
and -0.038dex/kpc for the outer regions (R>=3kpc). | | Source: | arXiv, arxiv.0705.3116 | | Services: | Forum | Review | PDF | Favorites | |
|
|
No review found.
Did you like this article?
Note: answers to reviews or questions about the article must be posted in the forum section.
Authors are not allowed to review their own article. They can use the forum section.
browser Mozilla/5.0 AppleWebKit/537.36 (KHTML, like Gecko; compatible; ClaudeBot/1.0; +claudebot@anthropic.com)
|
| |
|
|
|
|
News, job offers and information for researchers and scientists:
| |
REGISTER