2008/04/01 by L. Affer, G. Micela, T. Morel
Physics and Astronomy · #Astro and Planetary Science #Astrophysics and Star Formation Studies #Stellar, planetary, and galactic studies #astro-ph
paper · pdf · doi:10.1051/0004-6361:200809383
14 pages, 10 figures. Accepted for publication in A&A
openalex publication_date 2008/04/01 · arxiv created 2008/04/08 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/04
Context. X-ray surveys allow to identify young, main-sequence stars in the solar neighborhood. Young, stellar samples, selected according to their activity, can be used to determine the stellar birthrate in the last billion years. The ROSAT North Ecliptic Pole survey (NEP), with its moderately deep sensitivity (fluxes ≈10-14 erg cm-2 s-1), is the best survey, to date, able to sample the intermediate-age (10 years) nearby population. The identification process of NEP X-ray sources resulted in 144 X-ray sources having a normal stellar counterpart, with an excess of yellow stars with respect to model predictions.