New exocomets of $\beta$ Pic

TL;DR

This study analyzes TESS light curves of Beta Pictoris to identify and characterize shallow, aperiodic exocomet transits, revealing new events and confirming the non-periodic nature of these dips.

Contribution

It introduces the detection of five new aperiodic exocomet-like transits in Beta Pictoris and confirms the non-periodic, shallow nature of these events using TESS data.

Findings

Recovered previously known exocomet events.

Discovered five new aperiodic dips with asymmetric profiles.

Dips are shallow, less than 0.03% flux drop, lasting under a day.

Abstract

Aims. The aim of our work is to analyze the light curves of $\beta$ Pic recently observed by TESS in sectors 32, 33, and 34, searching for the signatures of exocomet transits. Methods. We process the $\beta$ Pic light curves from the MAST database, applying the frequency analysis to remove harmonic signals due to the star's pulsations and use a simple 1-D model to fit the profiles of the found events. Results. We recover events previously found by other authors in sectors 5 and 6 and find 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 $\beta$ 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. It indicates that aperiodic shallow dips are not likely an exceptional phenomenon, at least for the $\beta$ Pic system.