| Autor: |
Riccardo Spinelli, Elena Gallo, Francesco Haardt, Andrea Caldiroli, Federico Biassoni, Francesco Borsa, Emily Rauscher |
| Jazyk: |
angličtina |
| Rok vydání: |
2023 |
| Předmět: |
|
| Zdroj: |
The Astronomical Journal, Vol 165, Iss 5, p 200 (2023) |
| Druh dokumentu: |
article |
| ISSN: |
1538-3881 |
| DOI: |
10.3847/1538-3881/acc336 |
| Popis: |
We leverage Gaia DR2 parallactic distances to deliver new or revised estimates of planetary parameters and X-ray irradiation for a distance-limited (≲100 pc) sample of 27 gaseous planets (from super-Earths to hot Jupiters) with publicly available Chandra and/or XMM observations, for which we carry out a homogeneous data reduction. For 20 planets with X-ray-detected host stars we make use of the photoionization hydrodynamics code ATES to derive updated atmospheric mass outflow rates. The newly derived masses/radii are not consistent with the exoplanet.eu values for five systems: HD 149026b and WASP-38, for mass, and Au Mic b, HAT-P-20, and HAT-P-2 for radii. Notably, the lower mass implies a (Saturn-like) density of 0.86 ± 0.09 g cm ^−3 for HD 149026b. This independent estimate is consistent with the lowest values reported in the literature. Separately, we report on the X-ray detection of GJ 9827, HD 219134, and LHS 1140 for the first time. The inferred stellar X-ray luminosity of LHS 1140 ( ${1.34}_{-0.21}^{+0.19}\times {10}^{26}$ erg s ^−1 ) implies that LHS 1140 b is the least irradiated transiting super-Earth known to orbit within the habitable zone of a nearby M dwarf. |
| Databáze: |
Directory of Open Access Journals |
| Externí odkaz: |
|
