arXiv subjects

C. R. Foley

Publications and source records attributed to C. R. Foley.

3 recordsLinked to original sources

arXiv2002

High-resolution X-ray spectroscopy of Procyon by Chandra and XMM-Newton

We report the analysis of the high-resolution soft X-ray spectrum of the nearby F-type star Procyon in the wavelength range from 5 to 175 Angstrom obtained with the Low Energy Transmission Grating Spectrometer (LETGS) on board Chandra and with the Reflection Grating Spectrometers (RGS) and the EPIC-MOS CCD spectrometers on board XMM-Newton. Line fluxes have been measured separately for the RGS and LETGS. Spectra have been fitted globally to obtain self-consistent temperatures, emission measures, and abundances. The total volume emission measure is ~4.1 x 10e50/cm3 with a peak between 1 and 3 MK. No indications for a dominant hot component (T > 4 MK) were found. We present additional evidence for the lack of a solar-type FIP-effect, confirming earlier EUVE results.

astro-ph↗

arXiv2001

A Study of the Coronal Plasma in RS CVn binary systems: HR 1099 and co

XMM-Newton has been performing comprehensive studies of X-ray luminous RS CVn binary systems in its calibration and guaranteed time programs. We present results from ongoing investigations in the context of a systematic study of coronal emission from RS CVns. We concentrate here on coronal abundances and investigate the abundance pattern in RS CVn binaries as a function of activity and average temperature. We find a transition from an Inverse First Ionization Potential (FIP) effect towards an absence of a clear trend (no FIP) in intermediately active RS CVn systems. This scheme fits well into the long-term evolution from an IFIP to a FIP effect found in solar analogs. We further study variations in the elemental abundances during a large flare.

astro-ph↗

arXiv2001

A Study of the Coronal Plasma in RS CVn binary systems

XMM-Newton has been performing comprehensive studies of X-ray bright RS CVn binaries in its Calibration and Guaranteed Time programs. We present results from ongoing investigations in the context of a systematic study of coronal emission from RS CVns. We concentrate in this paper on coronal abundances and investigate the abundance pattern in RS CVn binaries as a function of activity and average temperature. A transition from an Inverse First Ionization Potential (FIP) effect towards an absence of a clear trend is found in intermediately active RS CVn systems. This scheme corresponds well into the long-term evolution from an IFIP to a FIP effect found in solar analogs. We further study variations in the elemental abundances during a large flare.

astro-ph↗