J/A+A/559/A35 FBS 0117+396 pulsating sdB star photometry (Ostensen+, 2013)
Binaries discovered by the MUCHFUSS project.
FBS 0117+396: An sdB+dM binary with a pulsating primary.
Ostensen R.H., Geier S., Schaffenroth V., Telting J.H., Bloemen S.,
Nemeth P., Beck P.G., Lombaert R., Papics P.I., Tillich A., Ziegerer E.,
Fox Machado L., Littlefair S., Dhillon V., Aerts C., Heber U.,
Maxted P.F.L., Gansicke B.T., Marsh T.R.
<Astron. Astrophys. 559, A35 (2013)>
=2013A&A...559A..35O 2013A&A...559A..35O
ADC_Keywords: Stars, double and multiple ; Stars, subdwarf ; Photometry
Keywords: subdwarfs - surveys - binaries: close - stars: oscillations -
stars: individual: FBS 0117+396
Abstract:
The project Massive Unseen Companions to Hot Faint Underluminous Stars
from SDSS (MUCHFUSS) aims to discover subdwarf-B stars with massive
compact companions such as overmassive white dwarfs (M>1.0M☉),
neutron stars or black holes. From the 127 subdwarfs with substantial
radial-velocity variations discovered in the initial survey, a number
of interesting objects have been selected for extensive follow-up.
After an initial photometry run with BUSCA revealed that FBS0117+396
is photometrically variable both on long and short timescales, we
chose it as an auxiliary target during a 6-night multi-color
photometry run with Ultracam. Spectroscopy was obtained at a number of
observatories in order to determine the binary period and obtain a
radial-velocity amplitude. After establishing an orbital period of
P=0.252d, and removing the signal associated with the irradiated
hemisphere of the M-dwarf companion, we were able to detect ten
pulsation periods in the Fourier spectrum of the light curve. Two
pulsation modes are found to have short periods of 337 and 379s, and
at least eight modes are found with periods between 45-min and 2.5h.
This establishes that FBS0117+396 is an sdB+dM reflection binary, in
which the primary is a hybrid pulsator, and the first one found with
this particular melange of flavours.
Description:
The three tables contain the photometry from different observatories
as plotted with different colours in Figure 6 of the paper.
Objects:
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RA (2000) DE Designation(s)
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01 20 22.95 +39 50 59.3 FBS 0117+396 = 2MASS J01202295+3950593
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File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
ucam.dat 25 13945 Photometry from WHT/Ultracam (55790-55795)
merc.dat 25 1784 Photometry from Mercator/MeropeII (55787-55802)
oan.dat 25 367 Photometry from OAN-SPM/Mexman (55800-55803)
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See also:
J/A+A/530/A28 : Priority targets for the MUCHFUSS project (Geier+, 2011)
Byte-by-byte Description of file: merc.dat oan.dat ucam.dat
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Bytes Format Units Label Explanations
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1- 13 F13.7 d Time Time of mid exposure (HJD-2400000)
15- 25 F11.8 --- Counts Normalised relative counts
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Acknowledgements:
Roy Ostensen, roy(at)ster.kuleuven.be
(End) Roy Ostensen [K.U. Leuven], Patricia Vannier [CDS] 03-Oct-2013