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J/ApJ/790/53          Photometric data of HD 209458b             (Zellem+, 2014)

The 4.5 µm full-orbit phase curve of the hot Jupiter HD 209458b. Zellem R.T., Lewis N.K., Knutson H.A., Griffith C.A., Showman A.P., Fortney J.J., Cowan N.B., Agol E., Burrows A., Charbonneau D., Deming D., Laughlin G., Langton J. <Astrophys. J., 790, 53 (2014)> =2014ApJ...790...53Z (SIMBAD/NED BibCode)
ADC_Keywords: Photometry ; Stars, double and multiple ; Planets Keywords: atmospheric effects - methods: numerical - planets and satellites: general - planets and satellites: individual: HD 209458b - techniques: photometric Abstract: The hot Jupiter HD 209458b is particularly amenable to detailed study as it is among the brightest transiting exoplanet systems currently known (V-mag = 7.65; K-mag = 6.308) and has a large planet-to-star contrast ratio. HD 209458b is predicted to be in synchronous rotation about its host star with a hot spot that is shifted eastward of the substellar point by superrotating equatorial winds. Here we present the first full-orbit observations of HD 209458b, in which its 4.5 µm emission was recorded with Spitzer/IRAC. Our study revises the previous 4.5 µm measurement of HD 209458b's secondary eclipse emission downward by ∼35% to 0.1391%-0.0069%+0.0072%, changing our interpretation of the properties of its dayside atmosphere. We find that the hot spot on the planet's dayside is shifted eastward of the substellar point by 40.°9±6.°0, in agreement with circulation models predicting equatorial superrotation. HD 209458b's dayside (Tbright= 1499±15 K) and nightside (Tbright= 972±44 K) emission indicate a day-to-night brightness temperature contrast smaller than that observed for more highly irradiated exoplanets, suggesting that the day-to-night temperature contrast may be partially a function of the incident stellar radiation. The observed phase curve shape deviates modestly from global circulation model predictions potentially due to disequilibrium chemistry or deficiencies in the current hot CH4 line lists used in these models. Observations of the phase curve at additional wavelengths are needed in order to determine the possible presence and spatial extent of a dayside temperature inversion, as well as to improve our overall understanding of this planet's atmospheric circulation. Description: The observations were taken between 2010 January 17 20:55:24.4 UT and 2010 January 21 21:28:42.0 UT, resulting in 96.55 hr of data. They begin shortly before secondary eclipse, continue through primary transit, and end shortly after secondary eclipse. To minimize readout time and thereby maximize image cadence, the subarray mode was used in which 32 x 32 pixel images were stored as sets of 64 in a single FITS datacube with a single image header. By assuming uniform spacing in time, the mid-exposure time for each image is calculated from the header keywords MBJD_OBS (start of the first image in each cube), AINTBEG (integration begin), and ATIMEEND (integration end). Effectively, the image spacing is 0.4 s. We report our timing measurements using BJD_UTC. For this analysis, the orbital period (P = 3.5247455 days) and eccentricity (e = 0) are fixed. Objects: ---------------------------------------------------------- RA (ICRS) DE Designation(s) ---------------------------------------------------------- 22 03 10.8 +18 53 04 HD 209458b = NAME Osiris ---------------------------------------------------------- File Summary:
FileName Lrecl Records Explanations
ReadMe 80 . This file table1.dat 96 754282 Photometric data
See also: J/A+A/508/1509 : Sky maps for hot Jupiters (Heller+, 2009) Byte-by-byte Description of file: table1.dat
Bytes Format Units Label Explanations
1- 20 F20.16 d BJD Barycentric Julian Date (UTC) - BJD-2455000 22- 39 F18.16 --- RFlux Raw, filtered relative flux 41- 58 F18.16 --- e_RFlux Uncertainty in RFlux 60- 77 F18.16 --- FFlux Final, corrected relative flux 79- 96 F18.16 --- e_FFlux Uncertainty in FFlux
History: From electronic version of the journal
(End) Prepared by [AAS], Tiphaine Pouvreau [CDS] 17-Mar-2017
The document above follows the rules of the Standard Description for Astronomical Catalogues.From this documentation it is possible to generate f77 program to load files into arrays or line by line

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