J/A+A/625/L13 TESS light curve of beta Pictoris (Zieba+, 2019)
Transiting exocomets detected in broadband light by TESS in the beta Pictoris
system.
Zieba S., Zwintz K., Kenworthy M., Kennedy G.M.
<Astron. Astrophys. 625, L13 (2019)>
=2019A&A...625L..13Z 2019A&A...625L..13Z (SIMBAD/NED BibCode)
ADC_Keywords: Stars, nearby ; Comets ; Photometry, CCD ; Space observations
Keywords: comets: general - planetary systems -
stars: individual: beta Pictoris - techniques: photometric -
circumstellar matter
Abstract:
We search for signs of falling evaporating bodies (FEBs, also known as
exocomets) in photometric time series obtained for β Pictoris
after fitting and removing its δ Scuti-type pulsation
frequencies.
Using photometric data obtained by the TESS satellite we determined
the pulsational properties of the exoplanet host star β Pictoris
through frequency analysis. We then pre-whitened the 54 identified
δ Scuti p-modes and investigated the residual photometric time
series for the presence of FEBs.
We identify three distinct dipping events in the light curve of β
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 disc of the
star.
We present the first broadband detections of exocomets crossing the
disc of β Pictoris, complementing the predictions made 20 years
earlier by Lecavelier Des Etangs et al. (1999A&A...343..916L 1999A&A...343..916L). 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.
Description:
Reduced 105-day long light curve for beta Pictoris obtained with the
NASA Transiting Exoplanet Survey Satellite (TESS) from 19 October 2018
to 1 February 2019. The first column lists the time in Barycentric
TESS Julian Date (BTJD) which is defined as the Barycentric Julian
Date (BJD-2457000.0). The second column is the reduced flux in
instrumental magnitudes.
Objects:
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RA (2000) DE Designation(s)
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05 47 17.09 -51 03 59.4 beta Pic = HR 2020
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File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
tessbpic.dat 32 62976 Time and magnitudes
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See also:
J/A+A/299/557 : Light variations on Beta Pic (Lecavelier des Etangs+, 1995)
Byte-by-byte Description of file: tessbpic.dat
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Bytes Format Units Label Explanations
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1- 14 F14.9 d Obs.Date Observation date (BJD-2457000.0)
15- 32 F18.14 --- Flux Reduced flux in instrumental magnitudes
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Acknowledgements:
Konstanze Zwintz, konstanze.zwintz(at)uibk.ac.at
(End) Konstanze Zwintz [Univ. Innsbruck], Patricia Vannier [CDS] 27-Apr-2019