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J/ApJ/786/2   Spitzer photometric time series of HD 97658   (Van Grootel+, 2014)

Transit confirmation and improved stellar and planet parameters for the super-Earth HD 97658 b and its host star. Van Grootel V., Gillon M., Valencia D., Madhusudhan N., Dragomir D., Howe A.R., Burrows A.S., Demory B.-O., Deming D., Ehrenreich D., Lovis C., Mayor M., Pepe F., Queloz D., Scuflaire R., Seager S., Segransan D., Udry S. <Astrophys. J., 786, 2 (2014)> =2014ApJ...786....2V (SIMBAD/NED BibCode)
ADC_Keywords: Stars, double and multiple ; Planets ; Photometry, infrared ; Binaries, eclipsing Keywords: binaries: eclipsing - planetary systems - stars: individual: HD 97658 - techniques: photometric - techniques: radial velocities Abstract: Super-Earths transiting nearby bright stars are key objects that simultaneously allow for accurate measurements of both their mass and radius, providing essential constraints on their internal composition. We present here the confirmation, based on Spitzer transit observations, that the super-Earth HD 97658 b transits its host star. HD 97658 is a low-mass (M*=0.77±0.05 M) K1 dwarf, as determined from the Hipparcos parallax and stellar evolution modeling. To constrain the planet parameters, we carry out Bayesian global analyses of Keck-High Resolution Echelle Spectrometer (Keck-HIRES) radial velocities and Microvariability and Oscillations of STars (MOST) and Spitzer photometry. HD 97658 b is a massive (Mp=7.55-0.79+0.83 M{earth}) and large (Rp=2.2470.095+0.098 R{earth} at 4.5 µm) super-Earth. We investigate the possible internal compositions for HD 97658 b. Our results indicate a large rocky component, of at least 60% by mass, and very little H-He components, at most 2% by mass. We also discuss how future asteroseismic observations can improve the knowledge of the HD 97658 system, in particular by constraining its age. Orbiting a bright host star, HD 97658 b will be a key target for upcoming space missions such as the Transiting Exoplanet Survey Satellite (TESS), the Characterizing Exoplanet Satellite (CHEOPS), the Planetary Transits and Oscillations of stars (PLATO), and the James Webb Space Telescope to characterize thoroughly its structure and atmosphere. Description: We monitored HD 97658 with Spitzer's IRAC camera on 2013 August 10 from 13:01:00 to 18:27:00 UT, corresponding to a transit window as computed from the MOST transit ephemeris (Dragomir et al. 2013, J/ApJ/772/L2). These Spitzer data were acquired in the context of the Cycle 9 program 90072 (PI: M. Gillon) dedicated to the search for the transits of RV-detected low-mass planets. They consist of 2320 sets of 64 individual subarray images obtained at 4.5 µm with an integration time of 0.08 s. They are available on the Spitzer Heritage Archive database under the form of 2320 Basic Calibrated Data files calibrated by the standard Spitzer reduction pipeline (version S19.1.0). Objects: ----------------------------------------------------- RA (ICRS) DE Designation(s) ----------------------------------------------------- 11 14 33.16 +25 42 37.4 HD 97658 b = HD 97658b 11 14 33.16 +25 42 37.4 HD 97658 = HIP 54906 ----------------------------------------------------- File Summary:
FileName Lrecl Records Explanations
ReadMe 80 . This file table1.dat 104 2320 Spitzer photometric time series of HD 97658, as used by our MCMC algorithm
See also: J/ApJ/759/L41 : New radial velocities of HD 97658 (Dragomir+, 2012) J/ApJ/772/L2 : Keck/HIRES radial velocities for HD 97658 (Dragomir+, 2013) Byte-by-byte Description of file: table1.dat
Bytes Format Units Label Explanations
1- 15 F15.10 d BJD Barycentric Julian Date; UTC (BJD-2450000) 17- 26 F10.8 --- Flux Normalized Spitzer/IRAC 4.5 micron flux 28- 41 E14.8 --- e_Flux Error in Flux 43- 53 F11.8 pix dX Spitzer X pixel coordinate 55- 65 F11.8 pix dY Spitzer Y pixel coordinate 67- 72 F6.4 pix FWHM FWHM of source 74- 83 F10.8 pix FWHMX X component of FWHM 85- 94 F10.8 pix FWHMY Y component of FWHM 96-104 F9.6 --- Sky Sky brightness in electrons
History: From electronic version of the journal
(End) Prepared by [AAS], Tiphaine Pouvreau [CDS] 20-Jul-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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