J/A+A/654/A60 HD 22496 b ESPRESSO RVs (Lillo-Box+, 2021)
HD 22496 b: The first ESPRESSO stand-alone planet discovery.
Lillo-Box J., Faria J.P., Suarez-Mascareno A., Figueira P., Sousa S.G.,
Tabernero H., Lovis C., Silva A.M., Demangeon O.D.S., Benatti S.,
Santos N.C., Mehner A., Pepe F.A., Sozzetti A., Zapatero Osorio M.R.,
Gonzalez Hernandez J.I., Micela G., Hojjatpanah S., Rebolo R., Cristiani S.,
Adibekyan V., Allart R., Allende Prieto C., Cabral A., Damasso M.,
Di Marcantonio P., Lo Curto G., Martins C.J.A.P., Megevand D., Molaro P.,
Nunes N.J., Palle E., Pasquini L., Poretti E., Udry S.
<Astron. Astrophys. 654, A60 (2021)>
=2021A&A...654A..60L 2021A&A...654A..60L (SIMBAD/NED BibCode)
ADC_Keywords: Stars, double and multiple ; Exoplanets ; Radial velocities ;
Optical
Keywords: planets and satellites: detection -
planets and satellites: fundamental parameters -
planets and satellites: individual: HD 22496 -
techniques: radial velocities
Abstract:
The ESPRESSO spectrograph is a new powerful tool developed to detect
and characterize extrasolar planets. Its design allows an
unprecedented radial velocity precision (down to a few tens of cm/s)
and long-term thermomechanical stability.
We present the first stand-alone detection of an extrasolar planet by
blind radial velocity search using ESPRESSO; our aim is to show the
power of the instrument in characterizing planetary signals at
different periodicities in long observing time spans.
We used 41 ESPRESSO measurements of HD 22496 obtained within a time
span of 895 days with a median photon noise of 18cm/s. A radial
velocity analysis was performed to test the presence of planets in the
system and to account for the stellar activity of this K5-K7
main-sequence star. For benchmarking and comparison, we attempted the
detection with 43 archive HARPS measurements and in this work we
compare the results yielded by the two datasets. We also used four
TESS sectors to search for transits.
We find radial velocity variations compatible with a close-in planet
with an orbital period of P=5.09071±0.00026 days when simultaneously
accounting for the effects of stellar activity on longer timescales
(Prot=34.99-0.53+0.58 days). We characterize the physical and
orbital properties of the planet and find a minimum mass of
5.57-0.68+0.73M☉, right in the dichotomic regime between
rocky and gaseous planets. Although not transiting according to TESS
data, if aligned with the stellar spin axis, the absolute mass of the
planet must be below 16M☉. We find no significant evidence for
additional signals in the data with semi-amplitudes above 56cm/s at
95% confidence.
With a modest set of radial velocity measurements, ESPRESSO is capable
of detecting and characterizing low-mass planets and constraining the
presence of planets in the habitable zone of K dwarfs down to the
rocky-mass regime.
Description:
Detection and characterization of the exoplanet HD 22496 b with
ESPRESSO data.
Objects:
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RA (2000) DE Designation(s)
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03 35 00.94 -48 25 08.9 HD22496 = HIP 16711
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File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
rvs.dat 70 84 Radial velocity data set for HD22496
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Byte-by-byte Description of file: rvs.dat
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Bytes Format Units Label Explanations
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1- 14 F14.6 d BJD Barycentric Julian date
16- 23 F8.5 km/s RV Radial velocity corrected for instrument offset
25- 31 F7.5 km/s e_RV Radial velocity uncertainty
33- 38 F6.4 km/s FWHM FWHM of the CCF
40- 45 F6.4 km/s e_FWHM FWHM of the CCF uncertainty
47- 52 F6.4 km/s BIS Bisector span of the CCF
54- 59 F6.4 km/s e_BIS Bisector span of the CCF uncertainty
61- 70 A10 --- Inst Instrument
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Acknowledgements:
Jorge Lillo-Box, Jorge.Lillo(at)cab.inta-csic.es
(End) Lillo-Box Jorge [CAB], Patricia Vannier [CDS] 14-Sep-2021