Detection of X-ray emission from β Pictoris with XMM-Newton: a cool corona, a boundary layer or what?M. Hempel, J. Robrade, J.-U. Ness and J. H. M. M. SchmittA&A, 440 2 (2005) 727-734DOI: https://doi.org/10.1051/0004-6361:20042596