J/A+A/633/A133 HD 80653 RV time series (Frustagli+, 2020)
An ultra-short period rocky super-Earth orbiting the G2-star HD 80653.
Frustagli G., Poretti E., Milbourne T., Malavolta L., Mortier A.,
Singh V., Bonomo A.S., Buchhave L.A., Zeng L., Vanderburg A., Udry S.,
Andreuzzi G., Collier-Cameron A., Cosentino R., Damasso M., Ghedina A.,
Harutyunyan A., Haywood R.D., Latham D.W., Lopez-Morales M., Lorenzi V.,
Martinez Fiorenzano A.F., Mayor M., Micela G., Molinari E., Pepe F.,
Phillips D., Rice K., Sozzetti A.
<Astron. Astrophys. 633, A133 (2020)>
=2020A&A...633A.133F 2020A&A...633A.133F (SIMBAD/NED BibCode)
ADC_Keywords: Stars, double and multiple ; Radial velocities
Keywords: planets and satellites: detection -
planets and satellites: composition - techniques: radial velocities -
techniques: photometry - stars: individual: HD 80653
Abstract:
Ultra-short period (USP) planets are a class of exoplanets with
periods shorter than one day. The origin of this sub-population of
planets is st ill unclear, with different formation scenarios highly
dependent on the composition of the USP planets. A better
understanding of this class of exoplanets will, therefore, require an
increase in the sample of such planets that have accurate and precise
masses and radii, which also includes estimates of the level of
irradiation and information about possible companions.
Here we report a detailed characterization of a USP planet around the
solar-type star HD 80653 = EP 251279430 using the K2 light curve and
108 precise radial velocities obtained with the HARPS-N spectrograph,
installed on the Telescopio Nazionale Galileo. From the K2 C16 data,
we found one super-Earth planet (Rb=1.613±0.071R⊕)
transiting the star on a short-period orbit (Pb=0.719573±0.000021d).
From our radial velocity measurements, we constrained the mass of HD
80653 b to Mb=5.60±0.43M⊕. We also detected a clear longterm
trend in the radial velocity data. We derived the fundamental stellar
parameters and determined a radius of R*=1.22±0.01R☉ and
mass of M*=1.18±0.04M☉, suggesting that HD 80653 has an age
of 2.7±1.2Gyr.
The bulk density (rhob=7.4±1.1g/cm3) of the planet is consistent
with an Earth-like composition of rock and iron and no thick
atmosphere. Our analysis of the K2 photometry also suggests hints of a
shallow secondary eclipse with a depth of 8.1± 3.7ppm. Flux
variations along the orbital phase are consistent with zero. The most
important contribution might come from the day-side thermal emission
from the surface of the planet at T=3480K.
Description:
HD 80653 was observed by K2 for about 80 days between 2017 December 9
and 2018 February 25. The raw images were downloaded from the Mikulski
Archive for Space Telescopes (MAST), and the light curve was extracted
from the calibrated pixel files.
The 115 spectra were collected from November 2018 to May 2019 with the
HARPS-N spectrograph (R=115000) installed on the 3.6-m Telescopio
Nazionale Galileo (TNG), located at the Observatorio del Roque de los
Muchachos in La Palma, Spain. All the spectra were taken with an
exposure time of 900s. Seven spectra with low signal-to-noise ratio
(S/N) taken on two nights were no longer considered. The 108 remaining
spectra have S/N in the range 40–127 (median S/N=84) at 550nm.
The 108 time series of the RVs and activity indicators, were obtained
reducing the spectra with the version 3.8 of the HARPS-N Data
Reduction Software (DRS), which includes corrections for color
systematics introduced by variations in observing conditions. A
numerical weighted G2 mask was used to calculate the weighted cross
correlation function. Error bars on the FWHM and BIS values have been
taken as twice those of the RV ones.
Objects:
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RA (2000) DE Designation(s)
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09 21 21.42 +14 22 04.5 HD 80653 = BD+14 2079
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File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
hd80653.dat 65 108 Time series of the RVs and activity indicators
(table B1)
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Byte-by-byte Description of file: hd80653.dat
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Bytes Format Units Label Explanations
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1- 14 F14.6 d BJD Barycentric Julian Date
16- 22 F7.5 km/s RV Radial Velocity
24- 30 F7.5 km/s e_RV Radial velocity error
32- 38 F7.5 km/s FWHM Full width at half maximum
40- 47 F8.5 km/s BIS Bisector inverse slope
49- 56 F8.6 --- SMW Mount Wilson S-index
58- 65 F8.6 --- e_SMW Mount Wilson S-index error
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Acknowledgements:
Giuseppe Frustagli, giuseppe.frustagli(at)inaf.it
(End) Patricia Vannier [CDS] 22-Dec-2019