English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

Atmospheric escape from close-in exoplanets is thought to be crucial inshaping observed planetary populations. Recently, significant progress has beenmade in observing this process in action through excess absorption in transitspectra and narrowband light curves. We model the escape ofinitially-homogeneous planetary winds interacting with a stellar wind. The rampressure balance of the two winds governs this interaction. When theimpingement of the stellar wind on the planetary outflow is mild or moderate,the planetary outflow expands nearly spherically through its sonic surfacebefore forming a shocked boundary layer. When the confinement is strong, theplanetary outflow is redirected into a cometary tail before it expands to itssonic radius. The resultant transmission spectra at the He 1083 nm line areaccurately represented by a 1D spherical wind solution in cases of mild tomoderate stellar wind interaction. In cases of strong stellar wind interaction,the degree of absorption is enhanced and the cometary tail leads to an extendedegress from transit. The crucial features of the wind--wind interaction are,therefore, encapsulated in the light curve of He 1083 nm equivalent width as afunction of time. The possibility of extended He 1083 nm absorption well beyondthe optical transit carries important implications for planning"out-of-transit" observations that serve as a baseline for in-transit data.

Stellar Wind Confinement of Evaporating Exoplanet Atmospheres and its Signatures in 1083 nm Observations