J/A+A/648/A15 beta Pictoris photometry (Kenworthy+, 2021)
Photometry from beta Pictoris Hill sphere transit campaign.
I. Photometric limits to dust and rings.
Kenworthy M.A., Mellon S.N., Bailey III J.I., Stuik R., Dorval P.,
Talens G.-J.J., Crawford S.R., Mamajek E.E., Laginja I., Ireland M.,
Lomberg B., Kuhn R.B., Snellen I., Zwintz K., Kuschnig R., Kennedy G.M.,
Abe L., Agabi A., Mekarnia D., Guillot T., Schmider F., Stee P., de Pra Y.,
Buttu M., Crouzet N., Kalas P., Wang J.J., Stevenson K., de Mooij E.,
Lagrange A.-M., Lacour S., Lecavelier des Etangs A., M. Nowak M.,
Strom P.A., Hui Z., Wang L.
<Astron. Astrophys. 648, A15 (2021)>
=2021A&A...648A..15K 2021A&A...648A..15K (SIMBAD/NED BibCode)
ADC_Keywords: Stars, A-type; Stars, variable ; Photometry, CCD
Keywords: planets and satellites: rings - planets and satellites: formation -
stars: individual: beta Pictoris
Abstract:
Photometric monitoring of beta Pictoris in 1981 showed anomalous
fluctuations of up to 4% over several days, consistent with foreground
material transiting the stellar disk. The subsequent discovery of the
gas giant planet beta Pictoris b and the predicted transit of its Hill
sphere to within 0.1 au projected distance of the planet provided an
opportunity to search for the transit of a circumplanetary disk in
this 21±4Myr-old planetary system. Continuous broadband photometric
monitoring of beta Pictoris requires ground- based observatories at
multiple longitudes to provide redundancy and to provide triggers for
rapid spectroscopic followup. These observatories include the
dedicated beta Pictoris monitoring observatory bRing at Sutherland and
Siding Springs, the ASTEP400 telescope at Concordia, and observations
from the space observatories BRITE and Hubble Space Telescope. We
search the combined light curves for evidence of short period
transient events caused by rings and for longer term photometric
variability due to diffuse circumplanetary material. We find no
photometric event that matches with the event seen in November 1981,
and there is no systematic photometric dimming of the star as a
function of the Hill sphere radius. We conclude that the 1981 event
was not caused by the transit of a circumplanetary disk around beta
Pictoris b. The upper limit on the long term variability of beta
Pictoris places an upper limit of 1.8x1022g of dust within the Hill
sphere. Circumplanetary material is either condensed into a
non-transiting disk, is condensed into a disk with moons that has a
small obliquity, or is below our detection threshold. This is the
first time that a dedicated international campaign has mapped the Hill
sphere transit of a gas giant extrasolar planet at 10 au.
Description:
Reduced light curves for beta Pictoris obtained with the four
observatories. The data for each observatory is rebinned to the same
epochs with anomalous photometry rejected and the standard deviation
of the remaining points used to estimate the error on the photometry.
brite1.dat - data from the BRITE-Constellation satellites bring1.dat -
data from the bRing telescopes in South Africa and Australia
astep1.dat - data from the ASTEP 400 telescope in Antarctica
The first column lists the Modified Julian Date for mid-exposure, the
second column is the normalised flux of the star minus one, the third
column is the standard deviation on the flux.
hst1.dat lists the data for the seven visits of the HST to beta
Pictoris. The star is deliberately drifted across the detector to
prevent saturation and increase the total signal measured.
The first column is the visit number, the second column the Julian
Date, the third column the total number of counts measured, and the
fourth column is the direction of the drift of the star across the
detector. The two opposite directions are represented by 1 and -1,
respectively.
Objects:
-------------------------------------------------
RA (2000) DE Designation(s)
-------------------------------------------------
05 47 17.09 -51 03 59.4 beta Pic = HR 2020
-------------------------------------------------
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
astep1.dat 28 2358 Photometry from ASTEP 400
brite1.dat 28 4347 Photometry from BRITE-Constellation
bring1.dat 26 2663 Photometry from bRing
hst1.dat 36 106 Photometry from HST
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See also:
J/A+A/299/557 : Light variations on beta Pic (Lecavelier des Etangs+, 1995)
J/A+A/542/A18 : βPic Harps radial velocity data (Lagrange+, 2012)
J/ApJ/823/108 : A dust model for bet Pic from 0.58 to 870um (Ballering+, 2016)
J/A+A/607/A25 : beta Pic HARPS spectrum (Vidal-Madjar+, 2017)
J/A+A/627/A28 : beta Pic BRITE, bRing, SMEI light curves (Zwintz+, 2019)
Byte-by-byte Description of file: astep1.dat brite1.dat
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Bytes Format Units Label Explanations
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1- 9 F9.3 d Time Observation date (MJD)
11- 20 E10.3 --- Flux [-1/1] Normalised flux to 1
22- 28 F7.5 --- e_Flux Error on flux
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Byte-by-byte Description of file: bring1.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 9 F9.3 d Time Observation date (MJD)
11- 20 E10.3 --- Flux [-1/1] Normalised flux to 1
22- 26 E5.1 --- e_Flux Error on Flux
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Byte-by-byte Description of file: hst1.dat
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Bytes Format Units Label Explanations
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1 I1 --- Visit [1/7] Visit number
3- 16 F14.6 d Time Observation date (MJD)
18- 33 F16.6 ct Flux Flux of star
35- 36 I2 --- Scandir [-1/1] Scan direction across detector
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Acknowledgements:
Matthew Kenworthy, kenworthy(at)strw.leidenuniv.nl
(End) Patricia Vannier [CDS] 22-Feb-2021