Transiting exocomets detected in broadband light by TESS in the $\beta$ Pictoris system

Abstract

We search for signs of falling evaporating bodies (FEBs, also known as exocomets) in photometric time series obtained for $\beta$ Pictoris after fitting and removing its $\delta$ Scuti type pulsation frequencies. Using photometric data obtained by the TESS satellite we determine the pulsational properties of the exoplanet host star $\beta$ Pictoris through frequency analysis. We then prewhiten the 54 identified $\delta$ Scuti p-modes and investigate the residual photometric time series for the presence of FEBs. We identify three distinct dipping events in the light curve of $\beta$ Pictoris over a 105-day period. These dips have depths from 0.5 to 2 millimagnitudes and durations of up to 2 days for the largest dip. These dips are asymmetric in nature and are consistent with a model of an evaporating comet with an extended tail crossing the disk of the star. We present the first broadband detections of exocomets crossing the disk of $\beta$ Pictoris, consistent with the predictions made 20 years earlier by Lecavelier Des Etangs et al. (1999). No periodic transits are seen in this time series. These observations confirm the spectroscopic detection of exocomets in Calcium H and K lines that have been seen in high resolution spectroscopy.

arXiv commentAccepted version updated with correct references to Rappaport et al. (2018) and various typos

References in corpus (29)

• Astropy: A Community Python Package for Astronomy
• emcee: The MCMC Hammer
• The NumPy array: a structure for efficient numerical computation
• Gaia Data Release 2. Summary of the contents and survey properties
• The Gaia mission
• The Transiting Exoplanet Survey Satellite
• Kepler Presearch Data Conditioning II - A Bayesian Approach to Systematic Error Correction
• A giant planet imaged in the disk of the young star Beta Pictoris
• Kepler Presearch Data Conditioning I - Architecture and Algorithms for Error Correction in Kepler Light Curves
• The TESS Input Catalog and Candidate Target List
• Overview of the Kepler Science Processing Pipeline
• On the age of the $\beta$ Pictoris moving group
• Planet Hunters X. KIC 8462852 - Where's the Flux?
• BRITE-Constellation: nanosatellites for precision photometry of bright stars
• Likely Transiting Exocomets Detected by Kepler
• The Orbit and Transit Prospects for $\beta$ Pictoris b constrained with One Milliarcsecond Astrometry
• Exocomets in the circumstellar gas disk of HD 172555
• Close stellar encounters with planetesimal discs: The dynamics of asymmetry in the Beta Pictoris system
• The secondary eclipses of WASP-19b as seen by the ASTEP 400 telescope from Antarctica
• Evidence for the disintegration of KIC 12557548 b
• The Inner Disk Structure, Disk-Planet Interactions, and Temporal Evolution in the Beta Pictoris System: A Two-Epoch HST/STIS Coronagraphic Study
• Thermalizing a telescope in Antarctica: Analysis of ASTEP observations
• Modelling the KIC8462852 light curves: compatibility of the dips and secular dimming with an exocomet interpretation
• An automated search for transiting exocomets
• Detection of a repeated transit signature in the light curve of the enigma star KIC 8462852: a 928-day period?
• Exocomet Orbit Fitting: Accelerating Coma Absorption During Transits of $\beta$ Pictoris
• The $\delta$ Scuti pulsations of $\beta$ Pictoris as observed by ASTEP from Antarctica
• bRing: An observatory dedicated to monitoring the $\beta$ Pictoris b Hill sphere transit
• Reaching sub-milimag photometric precision on Beta Pictoris with a nanosat: the PicSat mission

Cited by in corpus (42)

• orbitize!: A Comprehensive Orbit-fitting Software Package for the High-contrast Imaging Community
• Peering into the formation history of beta Pictoris b with VLTI/GRAVITY long baseline interferometry
• Exocomets size distribution in the $\beta$ Pictoris planetary system
• Exocomets: A spectroscopic survey
• Exocomets from a Solar System Perspective
• New exocomets of $\beta$ Pic
• The IAU Working Definition of an Exoplanet
• Primordial or Secondary? Testing models of debris disk gas with ALMA
• Planetesimals Around Stars with TESS (PAST): I. Transient Dimming of a Binary Solar Analog at the End of the Planet Accretion Era
• Hint of an exocomet transit in the CHEOPS lightcurve of HD 172555
• The far reaches of the beta Pictoris debris disk
• On the pollution of white dwarfs by exo-Oort cloud comets
• The Discovery of lambda Bootis Stars -- The Southern Survey II
• Tracing the formation and migration history: molecular signatures in the atmosphere of misaligned hot Jupiter WASP-94Ab using JWST NIRSpec/G395H
• Dynamical Mass Estimates of the $\beta$ Pictoris Planetary System Through Gaussian Process Stellar Activity Modelling
• Curves of growth for transiting exocomets: Application to Fe II lines in the Beta Pictoris system
• The TESS Mission Target Selection Procedure
• An unusually large gaseous transit in a debris disc
• Population of excited levels of Fe+, Ni+ and Cr+ in exocomets gaseous tails
• Imaging of exocomets with infrared interferometry
• CHEOPS's hunt for exocomets: photometric observations of 5 Vul
• Exocomets of $\beta$ Pictoris I: Exocomet destruction, sodium and disk line variability in 17 years of HARPS observations
• Abundances of refractory ions in Beta Pictoris exocomets
• Multi-wavelength aperture polarimetry of debris disc host stars
• Exocomet orbital distribution around $\beta$ Pictoris
• YOUNG Star detrending for Transiting Exoplanet Recovery (YOUNGSTER) II: Using Self-Organising Maps to explore young star variability in Sectors 1-13 of TESS data
• K2 Discovery of a Circumsecondary Disk Transiting EPIC 220208795
• Search for exocomets transits in Kepler light curves: Ten new transits identified
• Glancing through the debris disk: Photometric analysis of DE Boo with CHEOPS
• Transit distances and composition of low-velocity exocomets in the $\beta$ Pic system
• A nomenclature for individual exocomets
• Grazing, non-transiting disintegrating exoplanets observed with the planned Ariel space observatory -- A case study using Kepler-1520b
• The $\beta$ Pictoris b Hill sphere transit campaign. Paper II: Searching for the signatures of the $\beta$ Pictoris exoplanets through time delay analysis of the $\delta$ Scuti pulsations
• BeyonCE -- Light Curve Modelling Beyond Circular Eclipsers I. Shallot Explorer
• Extrasolar enigmas: from disintegrating exoplanets to exoasteroids
• A search for transits among the δ Scuti variables in Kepler
• VLTI/MATISSE observations of the hot dust around $\beta$ Pictoris: Observing faint objects with MATISSE
• The Inbound Gas and Dust Evolution of Interstellar Comet 3I/ATLAS from Optical Spectroscopy and Multi-band Photometry
• Potential sublimating exocomets around the young star PDS 70
• Follow-up of three exocomet-host candidates
• The Directly-Imaged Exoplanet Host Star 51 Eridani is a Gamma Doradus Pulsator
• Visual inspection of potential exocomet transits identified through machine learning and statistical methods