J/MNRAS/408/L51 2M1938+4603 (KIC 9472174) eclipses (Ostensen+, 2010)
2M1938+4603: a rich, multimode pulsating sdB star with an eclipsing dM companion
observed with Kepler.
Ostensen R.H., Green E.M., Bloemen S., Marsh T.R., Laird J.B., Morris M.,
Moriyama E., Oreiro R., Reed M.D., Kawaler S.D., Aerts C., Vuckovic M.,
Degroote P., Telting J.H., Kjeldsen H., Gilliland R.L.,
Christensen-Dalsgaard J., Borucki W.J., Koch D.
<Mon. Not. R. Astron. Soc., 408, L51-L55 (2010)>
=2010MNRAS.408L..51O 2010MNRAS.408L..51O
ADC_Keywords: Binaries, eclipsing ; Magnitudes
Keywords: binaries: close - binaries: eclipsing -
stars: individual: 2M1938+4603 - subdwarfs - stars: variables: general
Abstract:
2M1938+4603 (KIC 9472174) displays a spectacular light curve dominated
by a strong reflection effect and rather shallow, grazing eclipses.
The orbital period is 0.126d, the second longest period yet found for
an eclipsing sdB+dM, but still close to the minimum 0.1-d period among
such systems. The phase-folded Kepler light curve was used to detrend
the orbital effects from the data set. The amplitude spectrum of the
residual light curve reveals a rich collection of pulsation peaks
spanning frequencies from ∼50 to 4500uHz. The presence of a complex
pulsation spectrum in both the p- and g-mode regions has never before
been reported in a compact pulsator.
Description:
The discovery of the strong reflection effect with grazing eclipses
was made by two of us (JBL and MM) during a photometric run in 2008
June. Here we present only the eclipse timings from the ground-based
photometry, as the pulsations are too complex and have too low
amplitudes to be significant in those light curves.
Objects:
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RA (2000) DE Designation(s)
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19 38 32.6 +46 03 59 2M1938+4603 = KIC 9472174
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File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
tables1.dat 37 13 Primary minima from ground based data
tables2.dat 37 77 Primary minima from Kepler data
tables3.dat 35 72 Radial velocity measurements
tables4.dat 46 55 Frequencies, periods and amplitudes
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See also:
V/133 : Kepler Input Catalog (Kepler Mission Team, 2009)
Byte-by-byte Description of file: tables1.dat tables2.dat
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Bytes Format Units Label Explanations
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1- 4 I4 --- Epoch Epoch
7- 17 F11.5 d BJD Barycentric Julian date
21- 27 F7.5 d e_BJD rms uncertainty on BJD
30- 37 F8.5 d O-C Observed minus computed value
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Byte-by-byte Description of file: tables3.dat
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Bytes Format Units Label Explanations
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1- 16 F16.8 d HJD Heliocentric Julian date
19- 24 F6.2 km/s RV Radial velocity
27- 30 F4.2 km/s e_RV rms uncertainty on RV
33- 35 A3 --- Tel Telescope (1)
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Note (1): Telescope as follows:
Bok = B&C spectrograph on the 2.3-m Bok Telescope on Kitt Peak
MMT = Blue spectrograph on MMT observatory
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Byte-by-byte Description of file: tables4.dat
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Bytes Format Units Label Explanations
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1- 5 A5 --- ID Name of the frequency
6 A1 --- n_ID [+] Combined frequencies (1)
8- 15 F8.3 uHz Freq Frequency
17- 20 F4.3 uHz e_Freq rms uncertainty on Freq
23- 31 F9.3 s Per Period
33- 38 F6.3 s e_Per rms uncertainty on Per
42- 44 I3 umag Amp ?=- Amplitude
46 I1 umag e_Amp ?=- rms uncertainty on Amp
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Note (1): The two pairs of frequencies marked with "+" are unresolved.
Prewhitening one frequency with the measured amplitude leaves a significant
residual peak, but fitting two frequencies simultaneously produces possibly
exaggerated amplitudes and high errors on the frequencies. The amplitude
given is therefore only stated as the observed amplitude of the combined peak.
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History:
From electronic version of the journal
(End) Patricia Vannier [CDS] 04-Apr-2011