J/A+A/527/A8 Transiting planetary system WASP-7 (Southworth+, 2011)
A much lower density for the transiting extrasolar planet WASP-7.
Southworth J., Dominik M., Jorgensen U.G., Rahvar S., Snodgrass C.,
Alsubai K., Bozza V., Browne P., Burgdorf M., Calchi Novati S., Dodds P.,
Dreizler S., Finet F., Gerner T., Hardis S., Harpsoe K., Hellier C.,
Hinse T.C., Hundertmark M., Kains N., Kerins E., Liebig C., Mancini L.,
Mathiasen M., Penny M.T., Proft S., Ricci D., Scarpetta G., Schaefer S.,
Schoenebeck F., Surdej J.
<Astron. Astrophys. 527, A8 (2011)>
=2011A&A...527A...8S 2011A&A...527A...8S
ADC_Keywords: Stars, double and multiple ; Planets ; Photometry
Keywords: planets and satellites: fundamental parameters - planetary systems -
stars: individual: WASP-7
Abstract:
We present the first high-precision photometry of the transiting
extrasolar planetary system WASP-7, obtained using telescope
defocussing techniques and reaching a scatter of 0.68mmag per point.
We find that the transit depth is greater and that the host star is
more evolved than previously thought. The planet has a significantly
larger radius and much lower density and surface gravity than previous
measurements showed. Based on the revised properties it is no longer
an outlier in planetary mass-radius and period-gravity diagrams. We
obtain a more precise transit ephemeris for the WASP-7 system.
Description:
A light curve of one transit of the extrasolar planetary system WASP-7
is presented. The data were obtained using the Danish 1.5m telescope
and DFOSC camera at ESO La Silla in 2010, with substantial telescope
defocussing in order to improve the photometric precision of the
observations. A Johnson I filter and exposure times of 60s were used.
Objects:
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RA (2000) DE Designation(s)
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20 44 10.22 -39 13 30.9 WASP-7 = HD 197286
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File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
wasp7.dat 36 217 Defocussed photometry of WASP-7
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See also:
J/MNRAS/396/1023 : Transiting planetary system WASP-5 (Southworth+, 2009)
J/MNRAS/399/287 : Transiting planetary system WASP-4 (Southworth+, 2009)
J/ApJ/707/167 : Transiting planetary system WASP-18 (Southworth+, 2009)
J/MNRAS/408/1680 : Transiting planetary system WASP-2 (Southworth+, 2010)
Byte-by-byte Description of file: wasp7.dat
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Bytes Format Units Label Explanations
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1- 13 F13.7 d BJD(TDB) Barycentric JD for the midpoint of observation
16- 25 F10.7 mag Imag Differential I-band magnitude of WASP-7
28- 36 F9.7 mag e_Imag Measurement error of the I-band magnitude
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Acknowledgements:
John Southworth, jkt(at)astro.keele.ac.uk
(End) John Southworth [Keele Univ., UK], Patricia Vannier [CDS] 06-Jan-2011