Exoplanets & Exomoons

Measuring The Stellar And Planetary Properties Of The 51 Eridani System

By Keith Cowing
Status Report
January 4, 2024
Filed under , , , , , , , , ,
Measuring The Stellar And Planetary Properties Of The 51 Eridani System
Spectral energy distribution and spectrum of 51 Eridani. The black line is the NGSL and SpeX spectrum, with grey regions indicating a model. Photometry is shown in red, with horizontal error bars indicating the width of the filter, while vertical show the photometric uncertainty. Synthetic photometry from the spectrum is shown in green. The bottom panel shows the difference between the spectrum and photometry in units of standard deviations. — astro-ph.EP

In order to study exoplanets, a comprehensive characterization of the fundamental properties of the host stars, such as angular diameter, temperature, luminosity, and age, is essential, as the formation and evolution of exoplanets are directly influenced by the host stars at various points in time.

In this paper, we present interferometric observations taken of directly imaged planet host 51 Eridani at the CHARA Array. We measure the limb-darkened angular diameter of HD 29391 to be θLD=0.450±0.004 mas and combining with the Gaia zero-point corrected parallax, we get a stellar radius of 1.45±0.01 R⊙.

We use the PARSEC isochrones to estimate an age of 23.2+1.7−1.6 Myr and a mass of 1.550±0.005 M⊙. The age and mass agree well with values in the literature, determined through a variety of methods ranging from dynamical age trace-backs to lithium depletion boundary methods.

We derive a mass of 4.1+0.5−0.4 MJup for 51 Eri b using the Sonora Bobcat models, which further supports the possibility of 51 Eri b forming under either the hot-start formation model or the warm-start formation model.

Ashley Elliott, Tabetha Boyajian, Tyler Ellis, Kaspar von Braun, Andrew W. Mann, Gail Schaefer

Comments: 11 pages, 6 figures, 3 tables
Subjects: Earth and Planetary Astrophysics (astro-ph.EP)
Cite as: arXiv:2401.01468 [astro-ph.EP] (or arXiv:2401.01468v1 [astro-ph.EP] for this version)
Submission history
From: Ashley Elliott
[v1] Wed, 3 Jan 2024 00:06:17 UTC (1,648 KB)

Explorers Club Fellow, ex-NASA Space Station Payload manager/space biologist, Away Teams, Journalist, Lapsed climber, Synaesthete, Na’Vi-Jedi-Freman-Buddhist-mix, ASL, Devon Island and Everest Base Camp veteran, (he/him) 🖖🏻