The HARPS search for southern extra-solar planets XXXV. The interesting case of HD41248: stellar activity, no planets?

摘要: The search for planets orbiting metal-poor stars is of uttermost importance our understanding the planet formation models. However, no dedicated searches have been conducted so far very low mass such objects. Only a few cases are thus known. Amongst these, HD41248 metal-poor, solar-type star on which resonant pair super-Earth like has In present paper we new program that using HARPS spectrograph to Neptunes and Super-Earths sample FGK dwarfs. We then detailed analysis an additional 162 radial velocity measurements HD41248, obtained within this program, with goal confirming existence proposed planetary system. analyzed precise velocities, spectrograph, together several stellar activity diagnostics line profile indicators. A careful shows evidence system previously announced. One signals, period about 25 days, shown be related rotational star, clearly seen in some proxies. remaining signal (P~18 days) could not convincingly retrieved data set. discuss possible causes complex (evolving) signals observed proposing they may explained by appearance disappearance active regions surface strong differential rotation, or combination sparse sampling region evolution.