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Related papers: Self-Consistent Modeling of Metastable Helium Exop…

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Escaping atmosphere has been detected by the excess absorption of Ly$\alpha$, H$\alpha$ and He triplet (10830$\rm\AA$) lines. Simultaneously modeling the absorption of the H$\alpha$ and He 10830 lines can provide useful constraints about…

Earth and Planetary Astrophysics · Physics 2022-09-21 Dongdong Yan , Kwang-il Seon , Jianheng Guo , Guo Chen , Lifang Li

The evolution of space technology in recent years, fueled by advancements in computing such as Artificial Intelligence (AI) and machine learning (ML), has profoundly transformed our capacity to explore the cosmos. Missions like the James…

Earth and Planetary Astrophysics · Physics 2025-10-13 Vasuda Trehan , Kevin H. Knuth , M. J. Way

Atmospheric escape is thought to significantly influence the evolution of exoplanets, especially for sub-Jupiter planets on short orbital periods. Theoretical models predict that hydrodynamic escape could erode the atmospheres of such…

Earth and Planetary Astrophysics · Physics 2024-08-22 Dion Linssen , Jim Shih , Morgan MacLeod , Antonija Oklopčić

Exoplanetary properties depend on stellar properties: to know the planet with accuracy and precision it is necessary to know the star as accurately and precisely as possible. Our immediate aim is to characterize in a homogeneous and…

(Abridged) The existence of an extended neutral hydrogen exosphere around small planets can be used as an evidence for the presence of water in their lower atmosphere but, to date, such feature has not been securely detected in rocky…

Earth and Planetary Astrophysics · Physics 2019-01-30 Leonardo A. dos Santos , Vincent Bourrier , David Ehrenreich , Shingo Kameda

Upper atmospheres of Hot Jupiters are subject to extreme radiation conditions that can result in rapid atmospheric escape. The composition and structure of the upper atmospheres of these planets are affected by the high-energy spectrum of…

Solar and Stellar Astrophysics · Physics 2015-06-23 J. M. Chadney , M. Galand , Y. C. Unruh , T. T. Koskinen , J. Sanz-Forcada

Transit observations in Ly-alpha of HD209458b and HD189733b revealed signatures of neutral hydrogen escaping the planets. We present a 3D particle model of the dynamics of the escaping atoms, and calculate theoretical Ly-alpha absorption…

Earth and Planetary Astrophysics · Physics 2015-06-16 Vincent Bourrier , Alain Lecavelier des Etangs

We present a 3D fully selfconsistent multi-fluid hydrodynamic aeronomy model to study the structure of a hydrogen dominated expanding upper atmosphere around the hot Jupiter HD 209458b and the warm Neptune GJ 436b. In comparison to previous…

Earth and Planetary Astrophysics · Physics 2018-11-21 I. F. Shaikhislamov , M. L. Khodachenko , H. Lammer , A. G. Berezutsky , I. B. Miroshnichenko , M. S. Rumenskikh

Multi-wavelength transit and secondary-eclipse light-curve observations are some of the most powerful techniques to probe the thermo-chemical properties of exoplanets. Although the large planet-to-star brightness contrast and few available…

Earth and Planetary Astrophysics · Physics 2016-04-06 Patricio E. Cubillos

The demographics of sub-Jovian planets around low-mass stars is dominated by populations of ``sub-Neptunes" and ``super-Earths", distinguished by the presence or absence of envelopes of low-molecular weight volatiles, i.e., H2, He, and H2O.…

Earth and Planetary Astrophysics · Physics 2025-04-16 Tatsuya Yoshida , Eric Gaidos

Detecting heavy atoms in the inflated atmospheres of giant exoplanets that orbit close to their parent stars is a key factor for understanding their bulk composition, and the processes that drive their expansion and interaction with the…

Earth and Planetary Astrophysics · Physics 2013-03-19 Lotfi Ben-Jaffel , Gilda Ballester

We present three transit observations of HD 189733 b obtained with the high-resolution spectrograph CARMENES at Calar Alto. A strong absorption signal is detected in the near-infrared He I triplet at 10830 \AA{} in all three transits.…

We investigate the evolution of the deuterium-to-hydrogen (D/H) mass ratio driven by EUV photoevaporation of hydrogen-rich atmospheres of close-in sub-Neptunes around solar-type stars. For the first time, the diffusion-limited approach in…

Earth and Planetary Astrophysics · Physics 2023-08-21 Pin-Gao Gu , Howard Chen

Space resolved concentrations of helium He metastable atoms in an atmospheric pressure radio-frequency micro-plasma jet were measured using tunable diode laser absorption spectroscopy. The spatial profile of metastable atoms in the volume…

Plasma Physics · Physics 2015-05-28 B Niermann , T Hemke , N Y Babaeva , M Böke , M J Kushner , T Mussenbrock , J Winter

Atmospheric properties of exoplanets can be constrained with transit spectroscopy. The signature of atomic sodium NaI, known to be present above the clouds, is a powerful probe of the upper atmosphere, where it can be best detected and…

Earth and Planetary Astrophysics · Physics 2015-05-06 A. Wyttenbach , D. Ehrenreich , C. Lovis , S. Udry , F. Pepe

Exoplanetary science is among the fastest evolving fields of today's astronomical research. Ground-based planet-hunting surveys alongside dedicated space missions (Kepler, CoRoT) are delivering an ever-increasing number of exoplanets, now…

Instrumentation and Methods for Astrophysics · Physics 2011-11-28 M. Tessenyi , M. Ollivier , G. Tinetti , J. P. Beaulieu , V. Coudé du Foresto , T. Encrenaz , G. Micela , B. Swinyard , I. Ribas , A. Aylward , J. Tennyson , M. R. Swain , A. Sozzetti , G. Vasisht , P. Deroo

Detecting exoplanet transits at X-ray wavelengths would provide a window into the effects of high energy irradiation on the upper atmospheres of planets. However, stars are relatively dim in the X-ray, making exoplanet transit detections…

Earth and Planetary Astrophysics · Physics 2024-08-14 Raven Cilley , George W. King , Lia Corrales

High resolution transit spectroscopy has proven to be a reliable technique for the characterization of the chemical composition of exoplanet atmospheres. Taking advantage of the broad spectral coverage of the CARMENES spectrograph, we…

Many of the exoplanets for which we can obtain the highest SNR transit spectra are tidally locked. The atmospheres on tidally-locked planets likely exhibit large differences between the day and night side of the planet, the poles, and the…

Earth and Planetary Astrophysics · Physics 2021-01-06 Brianna I. Lacy , Adam S. Burrows

Future direct-imaging exoplanet missions such as WFIRST/AFTA, Exo-C, and Exo-S will measure the reflectivity of exoplanets at visible wavelengths. The exoplanets to be observed will be located further away from their parent stars than is…

Earth and Planetary Astrophysics · Physics 2014-12-25 Renyu Hu