Bisector Measurements of HD 102272

TL;DR

This paper presents bisector analysis of HD 102272 to distinguish between planetary signals and stellar activity in radial velocity data, aiding in confirming exoplanet detections around giant stars.

Contribution

It introduces a bisector analysis method applied to spectra from the Pennsylvania - Torun Planet Search to validate planetary signals in red giants.

Findings

Bisector analysis helps differentiate planetary signals from stellar activity.

HD 102272 shows radial velocity variations consistent with planetary companions.

The method improves confidence in exoplanet detection around evolved stars.

Abstract

Searches for planets around massive stars are essential for developing general understanding of planet formation and evolution of the planetary systems. The main objective of the Pennsylvania - Torun Planet Search is detection of planets around G-K subgiants and giants through precision radial velocity (RV) measurements with iodine absorption cell using HET HRS spectrograph. However, the long period radial velocity variations of red giants may also have other than planetary nature (e.g. a non-radial pulsations or rotational modulation in presence of starspots). In this work we present bisector analysis of cross-correlation functions (CCF) constructed from the spectra used for radial velocity determination but cleaned from the iodine lines for the second red giant with planets from our survey HD 102272.