Search results for " Stars: Coronae"

showing 3 items of 23 documents

A detailed study of the rise phase of a long duration X-ray flare in the young star TWA 11B

2010

We analyzed a long duration flare observed in a serendipitous XMM-Newton detection of the M star CD-39 7717B (TWA 11B), member of the young stellar association TW Hya (~ 8 Myr). Only the rise phase (with a duration of ~ 35 ks) and possibly the flare peak were observed. We took advantage of the high count-rate of the X-ray source to carry out a detailed analysis of its spectrum during the whole exposure. After a careful analysis, we interpreted the rise phase as resulting from the ignition of a first group of loops (event A) which triggered a subsequent two-ribbon flare (event B). Event A was analyzed using a single-loop model, while a two-ribbon model was applied for event B. Loop semi-leng…

Young stellar objectAstrophysics::High Energy Astrophysical PhenomenaPhase (waves)FOS: Physical sciencesAstrophysicsAstrophysics::Cosmology and Extragalactic Astrophysicslaw.inventionSettore FIS/05 - Astronomia E AstrofisicalawIonizationAstrophysics::Solar and Stellar AstrophysicsEmission spectrumAstrophysics::Galaxy AstrophysicsPhysicsHigh Energy Astrophysical Phenomena (astro-ph.HE)X-rayAstronomy and AstrophysicsAstrophysics - Astrophysics of GalaxiesStarsSpace and Planetary ScienceAstrophysics of Galaxies (astro-ph.GA)astrofisica fisica stellare flares stars: activity stars: coronae stars: flare stars: individual: CD-39 7717B TWA 11B stars: pre-main sequenceAstrophysics::Earth and Planetary AstrophysicsAstrophysics - High Energy Astrophysical PhenomenaEvent (particle physics)Flare
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Activity-rotation relation in the young cluster h Per

2015

The activity-rotation relation in PMS stars is still an open issue. To bridge the gap between the well constrained case of MS stars and the puzzling case of very young PMS stars, we studied the activity-rotation relation in the young cluster h Persei. Because of its age (˜13 Myr) h Per contains both fast and slow rotators, allowing us therefore to test the different regimes of stellar dynamo. We analyzed a deep Chandra/ACIS-I observation to constrain the activity level of h Per members. Rotational periods were derived by tet{MorauxArtemenko2013}. From the comparison of the 1002 detected X-ray sources, and the 586 h Per members with measured rotational period, we obtained a final catalog of …

stars: activity stars: coronae stars: pre-main sequence stars: rotation X-rays: starsSettore FIS/05 - Astronomia E Astrofisica
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Chandra study of the eclipsing M dwarf binary, YY Gem

2012

The eclipsing M dwarf binary system, YY Gem, was observed using Chandra covering 140 ks (2Prot) in total, split into two even exposures separated by 0.76 d (0.94 Prot). The system was extremely active: three energetic flares were observed over the course of these observations. The flaring and non-flaring states of the system are analysed in this paper. The activity level increased between the first and second observations even during the quiescent (non-flaring) phases. An analysis of the dynamics of the X-ray-emitting plasma suggests that both components are significantly active. Contemporaneous Hα spectra also suggest that both components show similar levels of activity. The primary star i…

techniques: spectroscopic binaries: eclipsing stars: coronae stars: flare stars: magnetic field X-rays: starsspectroscopic binaries: eclipsing stars: coronae stars: flare stars: magnetic field X-rays: stars [techniques]Settore FIS/05 - Astronomia E Astrofisica
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