J/MNRAS/399/287 Transiting planetary system WASP-4 (Southworth+, 2009)
High-precision photometry by telescope defocussing.
II. The transiting planetary system WASP-4.
Southworth J., Hinse T.C., Burgdorf M.J., Dominik M., Hornstrup A.,
Jorgensen U.G., Liebig C., Ricci D., Thone C.C., Anguita T., Bozza V.,
Novati S.C., Harpsoe K., Mancini L., Masi G., Mathiasen M., Rahvar S.,
Scarpetta G., Snodgrass C., Surdej J., Zub M.
<Mon. Not. R. Astron. Soc., 399, 287-294 (2009)>
=2009MNRAS.399..287S 2009MNRAS.399..287S
ADC_Keywords: Planets ; Photometry
Keywords: stars: planetary systems - methods: data analysis -
methods: observational - techniques: photometric
Abstract:
We present and analyse light curves of four transits of the Southern
hemisphere extrasolar planetary system WASP-4, obtained with a
telescope defocussed so the radius of each point spread function was
17 arcsec (44 pixels). This approach minimises both random and
systematic errors, allowing us to achieve scatters of between 0.60 and
0.88mmag per observation over complete transit events. The light
curves are augmented by published observations and analysed using the
JKTEBOP code. The results of this process are combined with
theoretical stellar model predictions to derive the physical
properties of the WASP-4 system. WASP-4 is now one of the
best-quantified transiting extrasolar planetary systems, and
significant further progress requires improvements to our
understanding of the physical properties of low-mass stars.
Description:
Light curves of four transit events of the transiting extrasolar
planetary system WASP-4 are presented. The data were obtained using
the Danish 1.5m telescope and DFOSC camera at ESO La Silla in 2008,
with substantial telescope defocussing in order to improve the
photometric precision of the observations. A Cousins R filter and
exposure times of 120s were used.
Objects:
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RA (2000) DE Designation(s)
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23 34 15.1 -42 03 41 WASP-4 = USNO-B1.0 0479-0948995
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File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
wasp4.dat 37 452 Defocussed photometry of WASP-4 (table2)
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See also:
J/MNRAS/396/1023 : Transiting planetary system WASP-5 (Southworth+, 2009)
Byte-by-byte Description of file: wasp4.dat
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Bytes Format Units Label Explanations
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1- 14 F14.6 d HJD HJD for the midpoint of observation
17- 26 F10.7 mag Rmag Differential R-band magnitude of WASP-5
29- 37 F9.7 mag e_Rmag Measurement error of the R-band magnitude
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Acknowledgements:
John Southworth, jkt(at)astro.keele.ac.uk
References:
Southworth et al., Paper I 2009MNRAS.396.1023S 2009MNRAS.396.1023S, Cat. J/MNRAS/396/1023
(End) John Southworth [Keele Univ., UK], Patricia Vannier [CDS] 12-Oct-2009