New exocomets of β Pic

¹ Main Astronomical Observatory of the NAS of Ukraine, 27 Akademika Zabolotnoho Str., 03143 Kyiv, Ukraine
e-mail: yp@mao.kiev.ua
² Centre for Astrophysics Research, University of Hertfordshire, College Lane, Hatfield AL10 9AB, UK
³ Astronomical Observatory of Taras Shevchenko National University of Kyiv, 3 Observatorna Str., 04053 Kyiv, Ukraine

Received: 30 August 2021
Accepted: 25 February 2022

Abstract

Aims. The aim of our work is to analyze the light curves of β Pic which were recently observed by the Transiting Exoplanet Survey Satellite (TESS) in sectors 32, 33, and 34 by searching for the signatures of exocomet transits.

Methods. We processed the β Pic light curves from the Mikulski Archive for Space Telescopes database, applying the frequency analysis to remove harmonic signals due to the star’s pulsations, and we used a simple 1D model to fit the profiles of the events that were found.

Results. We recovered events previously found by other authors in sectors 5 and 6 and found five new distinct aperiodic dipping events with asymmetric shapes resembling the expected profiles due to the passage of a comet-like body across the star disk. These dips are rather shallow, with the flux drop at a level of 0.03% and a duration of less than 1 day. No periodic transits were found in the sectors investigated.

Conclusions. The depth and duration of the identified dips are similar to the recently discovered transits in the β Pic light curves from sector 5 of the TESS observations as well as to those found in the light curves of KIC 354116 and KIC 1108472 from the Kepler database. This indicates that aperiodic shallow dips are not likely an exceptional phenomenon, at least for the β Pic system.