Spectroscopic Estimate of Surface Gravity for a Planetary Member in the Orionis Cluster

Citations Over TimeTop 11% of 2003 papers

Abstract

We present intermediate-resolution (R=1500) near-infrared spectroscopy from 1.17 µm to 1.37 µm of the spectral type T planetary candidate member in the σ Orionis cluster SOri70 reported by Zapatero Osorio et al. (2002). The new data have been obtained with NIRSPEC at the Keck II telescope. The best fit of our mid-resolution spectrum of SOri70 with theoretical spectra gives log g=3.5±0.5 cms −2 and Teff=1,100 +200 −100 K. The low gravity of this object derived from spectral synthesis supports its youth and membership to the young σ Orionis cluster. Using evolutionary models for an age of 3 Myr, we obtain a mass of 3 MJup and a radius of 0.16 R⊙, independent of the distance to the object. Our analysis confirms that SOri70 is the lowest mass cluster planet so far identified in the galaxy.

Related Papers

• → First- versus second-generation planet formation in post-common envelope binary (PCEB) planetary systems(2014)78 cited
• → Distorted, nonspherical transiting planets: impact on the transit depth and on the radius determination(2011)59 cited
• → The instability of planetary systems in binaries: how the Kozai mechanism leads to strong planet—planet interactions(2007)53 cited
• → Disentangling the parameter space: the role of planet multiplicity in triggering dynamical instabilities on planetary systems around white dwarfs(2022)10 cited