J/A+A/459/557 Oscillation modes of PG 1325+101 (Silvotti+, 2006)
The rapidly pulsating subdwarf B star PG1325+101.
I. Oscillation modes from multisite observations.
Silvotti R., Bonanno A., Bernabei S., Fontaine G., Charpinet S., Leccia S.,
Kjeldsen H., Janulis R., Frasca A., Ostensen R., Kim S.-L., Park B.-G.,
Jiang X., Reed M.D., Patterson R.S., Gietzen K.M., Clark P.J., Wolf G.W.,
Lipkin Y., Formiggini L., Leibowitz E., Oswalt T.D., Rudkin M., Johnston K.,
Brassard P., Chayer P., Green E.M., Bergeron P.
<Astron. Astrophys. 459, 557 (2006)>
=2006A&A...459..557S 2006A&A...459..557S
ADC_Keywords: Stars, horizontal branch ; Stars, subdwarf
Keywords: stars: horizontal-branch - stars: oscillations - stars: interiors -
stars: individual: PG 1325+101
Abstract:
We present the results of 215h of time-series photometry on the
rapidly pulsating subdwarf B star PG 1325+101 (Teff=35000K,
logg=5.8, logN(He)/N(H)=-1.7), obtained during 25 days of observation
in Spring 2003 from nine different sites. As in previous observations,
the temporal spectrum is dominated by the main peak at 7255.55µHz,
with an amplitude of about 2.7% which, however, is dropped to about
1.7% in February 2005. No secondary peaks close to the dominant
pulsation mode are clearly detected. In addition, at least fourteen
more pulsation frequencies are found: three of them at 7704.92,
9380.17 and 14511.10µHz were already present in the discovery run
with small differences in frequency, probably due to 1-day aliasing
effects. The peak at 7704.92µHz belongs to a triplet of almost
equally spaced frequencies that could be due to rotational splitting
and would imply a rotational period of about 1.6 days. Based on the
results of this article, a detailed asteroseismic analysis of PG
1325+101 is presented in a separate paper (Charpinet et al.,
2996A&A...459..565C 2996A&A...459..565C, Paper II).
Objects:
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RA (2000) DE Designation(s)
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13 27 48 +09 54.9 PG 1325+101 = WD 1325+101
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File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
lcwhole.dat 77 58416 *PG1325+101 relative fluxes
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Note on lcwhole.dat : The table contains ALL reduced data, including also the
last run from BAO, quite noisy, that has not been used in our analysis.
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Byte-by-byte Description of file: lcwhole.dat
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Bytes Format Units Label Explanations
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1- 18 F18.10 d BJD Barycentric Julian Date of Observation
23- 29 F7.4 --- RFlux Relative flux in mmi (1mmi=0.1% variation) (1)
32- 77 A46 --- Com Comment on origin of that data subset (2)
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Note (1): The unit is milli modulation intensity (mmi), 1mmi=0.1% variation.
Note (2): Origin of the data:
sara = SARA 0.9m
mol = Moletai 1.65m
boao = BOAO 1.8m
sln = Serra La Nave 0.9m
baker = Baker 0.4m
KVA60 = kva60 = kva = La Palma 0.6m
wise = Wise 1.0m
loi = Loiano 1.5m
bao = BAO 0.85m
When the comment contains the acronym of more than one site, this
means that data from different sites have been averaged (using a
weighted average).
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Acknowledgements: R. Silvotti, silvotti(at)na.astro.it
(End) Patricia Vannier [CDS] 29-Sep-2006