Coronal properties of G-type stars in different evolutionary phases

Abstract

We report on the analysis of XMM-Newton observations of three G-type stars in very different evolutionary phases: the weak-lined T Tauri star HD 283572, the Zero Age Main Sequence star EK Dra and the Hertzsprung-gap giant star 31 Com. They all have high X-ray luminosity (10^31 erg/s for HD 283572 and 31 Com and 10^30 erg/s for EK Dra). We compare the Emission Measure Distributions (EMDs) of these active coronal sources, derived from high-resolution XMM-Newton grating spectra, as well as the pattern of elemental abundances vs. First Ionization Potential (FIP). We also perform time-resolved spectroscopy of a flare detected by XMM from EK Dra. We interpret the observed $EMD$s as the result of the emission of ensembles of magnetically confined loop-like structures with different apex temperatures. Our analysis indicates that the coronae of HD 283572 and 31 Com are very similar in terms of dominant coronal magnetic structures, in spite of differences in the evolutionary phase, surface gravity and metallicity. In the case of EK Dra the distribution appears to be slightly flatter than in the previous two cases, although the peak temperature is similar.

15 pages, 13 Postscript figures, to be published in A&A

References in corpus (9)

• The European Photon Imaging Camera on XMM-Newton: The MOS Cameras
• Collisional Plasma Models with APEC/APED: Emission Line Diagnostics of Hydrogen-like and Helium-like Ions
• Ionization balance for optically thin plasmas: rate coefficients for all atoms and ions of the elements H to Ni
• Three years in the coronal life of AB Dor. I. Plasma emission measure distributions and abundances at different activity levels
• Modeling an X-ray Flare on Proxima Centauri: evidence of two flaring loop components and of two heating mechanisms at work
• Far-UV Emissions of the Sun in Time: Probing Solar Magnetic Activity and Effects on Evolution of Paleo-Planetary Atmospheres
• A Far Ultraviolet Spectroscopic Explorer Survey of Coronal Forbidden Lines in Late-Type Stars
• Coronal structure geometries on pre-main sequence stars
• The distribution of emission measure, and of heating budget, among the loops in the corona

Cited by in corpus (24)

• The XMM-Newton Extended Survey of the Taurus Molecular Cloud (XEST)
• X-Ray Spectroscopy of Stars
• Coronal Loops: Observations and Modeling of Confined Plasma
• A survey of stellar X-ray flares from the XMM-Newton serendipitous source catalogue: Hipparcos-Tycho cool stars
• XMM-Newton observations of the sigma Ori cluster. II. Spatial and spectral analysis of the full EPIC field
• Magnetic fields on young, moderately rotating Sun-like stars II. EK Draconis (HD 129333)
• An XMM-Newton observation of the young open cluster NGC 2547: coronal activity at 30 Myr
• Spectral properties of X-ray bright variable sources in the Taurus Molecular Cloud
• XMM-Newton spectroscopy of the metal depleted T Tauri star TWA 5
• Corona and XUV emission modelling of the Sun and Sun-like stars
• Coronal abundances of X-ray bright pre-main sequence stars in the Taurus Molecular Cloud
• Reconstructing the XUV Spectra of Active Sun-like Stars Using Solar Scaling Relations with Magnetic Flux
• Photospheric and coronal abundances in solar-type stars: the peculiar case of Tau Bootis
• XUV emission of the young planet-hosting star V1298\,Tau from coordinated observations with XMM-Newton and HST
• LO Peg: surface differential rotation, flares, and spot-topographic evolution
• SMA detection of an extreme millimeter flare from the young class III star HD 283572
• The flaring and quiescent components of the solar corona
• Unbinned maximum-likelihood estimators for low-count data: Applications to faint X-ray spectra in the Taurus Molecular Cloud
• Multi-waveband detection of quasi-periodic pulsations in a stellar flare on EK Draconis observed by XMM-Newton
• Coronal density diagnostics with Si X: CHANDRA/LETGS observations of Procyon, $\alpha$ Cen A$&$B, Capella and $\epsilon$ Eri
• Astrophysics in 2005
• Soft X-ray heating as a mechanism of optical continuum generation in solar-type star superflares
• Do Young Suns Produce Frequent, Massive CMEs? Results from Five-year Dedicated Optical Observations of EK Draconis and V889 Hercules
• XMM-Newton and Suzaku Spectroscopic Studies of Unidentified X-ray Sources towards the Galactic Bulge: 1RXS J180556.1$-$343818 and 1RXS J173905.2$-$392615