Revisiting Proxima with ESPRESSO
A. Su\'arez Mascare\~no, J. P. Faria, P. Figueira, C. Lovis, M., Damasso, J. I. Gonz\'alez Hern\'andez, R. Rebolo, S. Cristiano, F. Pepe, N., C. Santos, M. R. Zapatero Osorio, V. Adibekyan, S. Hojjatpanah, A. Sozzetti,, F. Murgas, M. Abreo, M. Affolter, Y. Alibert, M. Aliverti

TL;DR
This study confirms Proxima b's existence using ESPRESSO spectrograph data, refines its orbital and mass parameters, and explores potential additional signals and stellar activity effects.
Contribution
It provides independent confirmation of Proxima b with improved precision and introduces methods to account for stellar activity in radial velocity measurements.
Findings
Proxima b confirmed at 11.218 days with a minimum mass of 1.29 Me.
Detected a potential second planet at 5.15 days with a semi-amplitude of 40 cm/s.
No evidence of additional companions above 0.6 Me within 50 days period.
Abstract
We aim to confirm the presence of Proxima b using independent measurements obtained with the new ESPRESSO spectrograph, and refine the planetary parameters taking advantage of its improved precision. We analysed 63 spectroscopic ESPRESSO observations of Proxima taken during 2019. We obtained radial velocity measurements with a typical radial velocity photon noise of 26 cm/s. We ran a joint MCMC analysis on the time series of the radial velocity and full-width half maximum of the cross-correlation function to model the planetary and stellar signals present in the data, applying Gaussian process regression to deal with stellar activity. We confirm the presence of Proxima b independently in the ESPRESSO data. The ESPRESSO data on its own shows Proxima b at a period of 11.218 0.029 days, with a minimum mass of 1.29 0.13 Me. In the combined dataset we measure a period of 11.18427…
Peer Reviews
No public reviews on file for this paper yet. If you reviewed it on a platform where reviews are public (OpenReview, ICLR, NeurIPS, ICML), you can paste yours below so the community can read it here.
Code & Models
Videos
No videos yet. Explain this paper in a talk, walkthrough, or lecture? Add one.
