@article{FosterPoppenhaegerAlvaradoGomezetal.2020,
  author    = {Foster, Mary Grace and Poppenh{\"a}ger, Katja and Alvarado-G{\´o}mez, Juli{\´a}n David and Schmitt, J{\"u}rgen},
  title     = {The corona of GJ 1151 in the context of star-planet interaction},
  series = {Monthly notices of the Royal Astronomical Society},
  volume    = {497},
  journal   = {Monthly notices of the Royal Astronomical Society},
  number    = {1},
  publisher = {Oxford Univ. Press},
  address   = {Oxford},
  issn      = {0035-8711},
  doi       = {10.1093/mnras/staa1982},
  pages     = {1015 -- 1019},
  year      = {2020},
  abstract  = {The low-mass star GJ 1151 has been reported to display variable low-frequency radio emission, which has been interpreted as a signpost of coronal star-planet interactions with an unseen exoplanet. Here we report the first X-ray detection of GJ 1151's corona based on the XMM-Newton data. We find that the star displays a small flare during the X-ray observation. Averaged over the observation, we detect the star with a low coronal temperature of 1.6 MK and an X-ray luminosity of L-X = 5.5 x 10(26) erg s(-1). During the quiescent time periods excluding the flare, the star remains undetected with an upper limit of L-X,L- qui <= 3.7 x 10(26) erg s(-1). This is compatible with the coronal assumptions used in a recently published model for a star-planet interaction origin of the observed radio signals from this star.},
  language  = {en}
}
@article{FosterPoppenhaegerIlićPetkovićetal.2022,
  author    = {Foster, Mary Grace and Poppenh{\"a}ger, Katja and Ilić Petković, Nikoleta and Schwope, Axel},
  title     = {Exoplanet X-ray irradiation and evaporation rates with eROSITA},
  series = {Astronomy and astrophysics : an international weekly journal},
  volume    = {661},
  journal   = {Astronomy and astrophysics : an international weekly journal},
  publisher = {EDP Sciences},
  address   = {Les Ulis},
  issn      = {0004-6361},
  doi       = {10.1051/0004-6361/202141097},
  pages     = {11},
  year      = {2022},
  abstract  = {High-energy irradiation is a driver for atmospheric evaporation and mass loss in exoplanets. This work is based on data from eROSITA, the soft X-ray instrument on board the Spectrum Roentgen Gamma mission, as well as on archival data from other missions. We aim to characterise the high-energy environment of known exoplanets and estimate their mass-loss rates. We use X-ray source catalogues from eROSITA, XMM-Newton, Chandra, and ROSAT to derive X-ray luminosities of exoplanet host stars in the 0.2-2 keV energy band with an underlying coronal, that is, optically thin thermal spectrum. We present a catalogue of stellar X-ray and EUV luminosities, exoplanetary X-ray and EUV irradiation fluxes, and estimated mass-loss rates for a total of 287 exoplanets, 96 of which are characterised for the first time based on new eROSITA detections. We identify 14 first-time X-ray detections of transiting exoplanets that are subject to irradiation levels known to cause observable evaporation signatures in other exoplanets. This makes them suitable targets for follow-up observations.},
  language  = {en}
}