EDP Sciences
Free access
Volume 445, Number 2, January II 2006
Page(s) 673 - 680
Section Stellar atmospheres
DOI http://dx.doi.org/10.1051/0004-6361:20053666

A&A 445, 673-680 (2006)
DOI: 10.1051/0004-6361:20053666

A compact flare eclipsed in the corona of SV Camelopardalis

J. Sanz-Forcada1, F. Favata1 and G. Micela2

1  Astrophysics Division - Research and Science Support Department of ESA, ESTEC, Postbus 299, 2200 AG Noordwijk, The Netherlands
    e-mail: [jsanz;ffavata]@rssd.esa.int
2  INAF - Osservatorio Astronomico di Palermo, Piazza del Parlamento 1, 90134 Palermo, Italy
    e-mail: giusi@astropa.unipa.it

(Received 20 June 2005 / Accepted 30 August 2005 )

The eclipsing active binary SV Cam (G0V/K6V, $P_{\rm
orb}=0.593071$ d) was observed with XMM-Newton during two campaigns in 2001 and 2003. No eclipses in the quiescent emission are clearly identified, but a flare was eclipsed during the 2001 campaign, allowing us to strongly constrain, from purely geometrical considerations, the position and size of the event: the flare is compact and it is formed at a latitude below 65$\degr$. The size, temperature and Emission Measure of the flare imply an electron density of $\log n_{\rm e}$ (cm $^{-3})\sim 10.6{-}13.3$ and a magnetic field of ~65-1400 G in order to confine the plasma, consistent with the measurements that are obtained from density-sensitive line ratios in other similar active stars. Average emission seems to come from either extended or polar regions because of lack of eclipses. The Emission Measure Distribution, coronal abundances and characteristics of variability are very similar to other active stars such as AB Dor (K1V).

Key words: stars: coronae -- stars: abundances -- stars: individual: SV Cam -- stars: late-type -- X-rays: stars -- binaries: eclipsing

SIMBAD Objects

© ESO 2005