High Precision {it K}-Shell Photoabsorption Cross Sections for Atomic Oxygen: Experiment and Theory

Дата и время публикации : 2013-05-21T23:13:51Z

Авторы публикации и институты :
B. M. McLaughlin
C. P. Ballance
K. P. Bowen
D. J. Gardenghi
W. C. Stolte

Ссылка на журнал-издание: Ссылка на журнал-издание не найдена
Коментарии к cтатье: Accepted for publication in Ap J Letters; 4 figures and a table
Первичная категория: astro-ph.HE

Все категории : astro-ph.HE, physics.atom-ph

Краткий обзор статьи: Photoabsorption of atomic oxygen in the energy region below the $rm 1s^{-1}$ threshold in x-ray spectroscopy from {it Chandra} and {it XMM-Newton} is observed in a variety of x-ray binary spectra. Photoabsorption cross sections determined from an R-matrix method with pseudo-states (RMPS) and new, high precision measurements from the Advanced Light Source (ALS) are presented. High-resolution spectroscopy with E/$Delta$E $approx$ 4,250 $pm$ 400 was obtained for photon energies from 520 eV to 555 eV at an energy resolution of 124 $pm$ 12 meV FWHM. {it K}-shell photoabsorption cross-section measurements were made with a re-analysis of previous experimental data on atomic oxygen at the ALS. Natural linewidths $Gamma$ are extracted for the $rm 1s^{-1}2s^22p^4 (^4P)np ^3P^{circ}$ and $rm 1s^{-1}2s^22p^4(^2P)np ~^3P^{circ}$ Rydberg resonances series and compared with theoretical predictions. Accurate cross sections and linewidths are obtained for applications in x-ray astronomy. Excellent agreement between theory and the ALS measurements is shown which will have profound implications for the modelling of x-ray spectra and spectral diagnostics.

Category: Physics