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arXiv · 2209.11314

X-ray Emission from the Exoplanet Hosting LTT 1445 Triple Star System

Alexander Brown·Cynthia S. Froning·Allison Youngblood·Kevin France·David J. Wilson·Girish Duvvuri·Yamila Miguel·Hannah Diamond-Lowe
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Abstract

JWST will be able to observe the atmospheres of rocky planets transiting nearby M dwarfs. The M dwarf triple star system LTT 1445, at a distance of 6.86 pc, hosts some of the nearest rocky terrestrial planets. These planets most likely orbit the M 3.5V star LTT 1445A. During a 28.6 ksec Chandra ACIS-S3 observation we have i) spatially resolved and detected all three stars in the LTT 1445 system, ii) measured the X-ray luminosity of the individual stars, including LTT 1445A, for the first time, iii) studied the flux variability of the X-ray sources and found strong variability from the A and C components, and iv) investigated how the coronal luminosities, temperatures and volume emission measures vary at different activity levels. Combining these X-ray data with upcoming HST ultraviolet observations will allow a differential emission measure (DEM) estimation of the star's EUV spectrum, thereby facilitating modeling of the rocky planets' atmospheres.

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Alexander Brown, Cynthia S. Froning, Allison Youngblood, Kevin France, David J. Wilson, Girish Duvvuri, Yamila Miguel, Hannah Diamond-Lowe. 2022-09-22. X-ray Emission from the Exoplanet Hosting LTT 1445 Triple Star System. https://doi.org/10.3847/1538-3881%2Fac8f25

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