Specific Star Forming Regions -- Poster Presentation
The COUP Abundance Study: Spectral analysis of the X-ray brightest
late-type stars in Orion
Antonio Maggio, INAF - Osservatorio Astronomico di Palermo
E. Flaccomio (OAPA), G. Micela (OAPA), S. Sciortino (OAPA), F. Favata (ESA), E.D. Feigelson (PSU)
We present preliminary results of a detailed X-ray spectral
analysis of 55 sources in the Chandra Orion Ultra-deep field, identified
with late-type stars and having more that 10^4 extracted counts. The aim
of this analysis is to provide a census of element abundances in the
coronae of these young stars, and to study possible dependences of such
abundances on the magnetic activity level, the presence of circumstellar
disks, indicators of accretion, and the properties of the local environment.
We present here the methodology of such an analysis and results related
to the thermal structure of the selected sources, their global metallicity,
and abundance determinations for some individual elements. In particular,
we show that the COUP X-ray bright sources tend to be metal poor (Fe
abundances less than half the solar one, with most frequent values of
0.1-0.2 solar), while they show a larger scatter of Ne abundances, and
Ne/Fe ratios from $\sim1$ up to $\sim10$.