J/AJ/166/143 Ha emission from FU Tau B brown dwarf companion (Wu+, 2023)
Monitoring Ha Emission from the Wide-orbit Brown-dwarf Companion FU Tau B
Wu Y.-L., Cheng Y.-C., Huang L.-C., Bowler B.P., Close L.M., Tseng W.-L.,
Chen N., Chen D.-W.
<Astron. J., 166, 143 (2023)>
=2023AJ....166..143W 2023AJ....166..143W
ADC_Keywords: Exoplanets; Stars, brown dwarf; Photometry, H-alpha
Keywords: Accretion ; Brown dwarfs ; Stellar accretion ; Time series
analysis ; Lomb-Scargle periodogram
Abstract:
Monitoring mass accretion onto substellar objects provides insights
into the geometry of the accretion flows. We use the Lulin One-meter
Telescope to monitor Hα emission from FUTauB, a ∼19MJup
brown-dwarf companion at 5.7" (719au) from the host star, for six
consecutive nights. This is the longest continuous Hα monitoring
for a substellar companion near the deuterium-burning limit. We aim to
investigate if accretion near the planetary regime could be
rotationally modulated as suggested by magnetospheric accretion
models. We find tentative evidence that Hα mildly varies on
hourly and daily timescales, though our sensitivity is not sufficient
to definitively establish any rotational modulation. No burst-like
events are detected, implying that accretion onto FUTauB is overall
stable during the time baseline and sampling windows over which it was
observed. The primary star FUTauA also exhibits Hα variations
over timescales from minutes to days. This program highlights the
potential of monitoring accretion onto substellar objects with small
telescopes.
Description:
We monitored the FU Tau system at Hα with the Lulin Observatory
in Taiwan (LOT) on UT 2021 December 4-9. The central wavelength and
the effective width of the Hα filter are 6562.8Å and
36.7Å, respectively. The Lulin CCD camera has a pixel scale of
0.383" and a field of view of 13.07x13.07'.
Objects:
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RA (2000) DE Designation(s)
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04 23 35.39 +25 03 02.7 FU Tau= V* FU Tau
04 24 14.46 +25 06 10.6 2MASSJ04241447+2506106 = 2MASS J04241447+2506106
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File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table2.dat 25 471 Relative photometry between FU Tau A and
2MASS J04241447+2506106
table3.dat 25 67 Relative photometry between FU Tau B and
2MASS J04241447+2506106
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See also:
I/352 : Distances 1.47 billion stars Gaia EDR3 (Bailer-Jones+, 2021)
J/A+A/349/619 : UBVRI light curves of AA Tau in 1995 (Bouvier+, 1999)
J/A+A/548/A56 : X-shooter spectra 12 young stellar objects (Rigliaco+, 2012)
J/A+A/551/A107 : X-shooter spectra of 24 young stellar objects (Manara+, 2013)
J/ApJS/208/9 : Intrinsic colors and temperatures of PMS stars (Pecaut+, 2013)
J/AJ/147/82 : Monitoring of disk-bearing stars in NGC 2264 (Cody+, 2014)
J/ApJ/788/40 : Late-type targets in Taurus, Cha I & UpperSco (Todorov+, 2014)
J/A+A/605/A86 : Pre-main sequence stars VLT/X-Shooter spectra (Manara+, 2017)
J/AJ/156/71 : K2 Campaign2 young disk-bearing stars in Sco&Oph (Cody+, 2018)
J/AJ/165/164 : Tull RVels, rotation periods and Inclinations (Bowler+, 2023)
Byte-by-byte Description of file: table[23].dat
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Bytes Format Units Label Explanations
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1- 13 F13.5 d HJD Heliocentric Julian date at
exposure midpoint
15- 19 F5.3 mag dmag Magnitude difference at Hα
21- 25 F5.3 mag e_dmag Uncertainty in dmag
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History:
From electronic version of the journal
(End) Prepared by [AAS], Coralie Fix [CDS], 08-Apr-2024