Bibcode
Lillo-Box, J.; Faria, J. P.; Suárez Mascareño, 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.; González Hernández, 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.; Pallé, E.; Pasquini, L.; Poretti, E.; Udry, S.
Bibliographical reference
Astronomy and Astrophysics
Advertised on:
10
2021
Journal
Citations
8
Refereed citations
8
Description
Context. 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−1) and long-term thermomechanical stability.
Aims: 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.
Methods: We used 41 ESPRESSO measurements of HD 22496 obtained within a time span of 895 days with a median photon noise of 18 cm s−1. 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.
Results: 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+0.73 M⊕, 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 16 M⊕. We find no significant evidence for additional signals in the data with semi-amplitudes above 56 cm s−1 at 95% confidence.
Conclusions: 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.
Aims: 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.
Methods: We used 41 ESPRESSO measurements of HD 22496 obtained within a time span of 895 days with a median photon noise of 18 cm s−1. 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.
Results: 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+0.73 M⊕, 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 16 M⊕. We find no significant evidence for additional signals in the data with semi-amplitudes above 56 cm s−1 at 95% confidence.
Conclusions: 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.
Full Table B.2 is only available at the CDS via anonymous ftp to cdsarc.u-strasbg.fr (ftp://130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/cat/J/A+A/654/A60
Based on Guaranteed Time Observations collected at the European Southern Observatory (ESO) under ESO programs 1102.C-074, 1104.C-0350, and 106.21M2 by the ESPRESSO Consortium.
Related projects
Very Low Mass Stars, Brown Dwarfs and Planets
Our goal is to study the processes that lead to the formation of low mass stars, brown dwarfs and planets and to characterize the physical properties of these objects in various evolutionary stages. Low mass stars and brown dwarfs are likely the most numerous type of objects in our Galaxy but due to their low intrinsic luminosity they are not so
Rafael
Rebolo López
Exoplanets and Astrobiology
The search for life in the universe has been driven by recent discoveries of planets around other stars (known as exoplanets), becoming one of the most active fields in modern astrophysics. The growing number of new exoplanets discovered in recent years and the recent advance on the study of their atmospheres are not only providing new valuable
Enric
Pallé Bago
Chemical Abundances in Stars
Stellar spectroscopy allows us to determine the properties and chemical compositions of stars. From this information for stars of different ages in the Milky Way, it is possible to reconstruct the chemical evolution of the Galaxy, as well as the origin of the elements heavier than boron, created mainly in stellar interiors. It is also possible to
Carlos
Allende Prieto