Independent Validation of the Temperate Super-Earth HD 79211 b using HARPS-N
Abstract

We present high-precision radial velocities (RVs) from the HARPS-N spectrograph for HD 79210 and HD 79211, two M0V members of a gravitationally bound binary system. We detect a planet candidate with a period of$24.421−0.017+0.016$days around HD 79211 in these HARPS-N RVs, validating the planet candidate originally identified in CARMENES RV data alone. Using HARPS-N, CARMENES, and RVs spanning a total of 25 yr, we further refine the planet candidate parameters toP= 24.422 ± 0.014 days,K= 3.19 ± 0.27 m s−1,Msini= 10.6 ± 1.2M, anda= 0.142 ± 0.005 au. We do not find any additional planet candidate signals in the data of HD 79211, nor do we find any planet candidate signals in HD 79210. This system adds to the number of exoplanets detected in binaries with M-dwarf members and serves as a case study for planet formation in stellar binaries.

Authors:
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Publication Date:
NSF-PAR ID:
10390089
Journal Name:
The Astronomical Journal
Volume:
165
Issue:
2
Page Range or eLocation-ID:
Article No. 38
ISSN:
0004-6256
Publisher:
DOI PREFIX: 10.3847
National Science Foundation
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