Open AccessA search for Ca ii emission enhancement in stars resulting from nearby giant planets
Author(s) -
Saar S. H.,
Cuntz M.
Publication year - 2001
Publication title -
monthly notices of the royal astronomical society
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.058
H-Index - 383
eISSN - 1365-2966
pISSN - 0035-8711
DOI - 10.1046/j.1365-8711.2001.04296.x
Subject(s) - physics , planet , astrophysics , stars , astronomy , dynamo , radiative transfer , stellar rotation , giant planet , planetary system , magnetic field , quantum mechanics
We present a search for periodicities ( P chr ) in the chromospheric Ca ii infrared triplet emission of several stars ( τ Boo, 51 Peg, υ And, ρ 1 Cnc, ρ CrB, 70 Vir and GL 876) which may be directly attributable to interaction with close‐in giant planets. Activity enhancements could arise from increased non‐radiative heating and dynamo action in planet‐induced tidal bulges (with P chr ≈P orb /2), or from interactions between the stellar and planetary magnetic fields (with P chr ≈P orb ). We compare both P chr and the phase dependence of the activity with the planetary orbital period P orb , the orbital phase, and models. No significant P chr or phase dependence attributable to planets can be clearly identified. We place approximate upper limits on the amplitude of any planet‐induced activity. We identify a possible stellar rotation period for GL 876, and support previous period determinations for four other stars. We discuss the results and possible directions of future research.