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 Plus monthly

Global: Zendy Tools annual

Global: Zendy Tools monthly

Global: Zendy Free Plan

The characterization of exoplanetary atmospheres via transit spectroscopy isbased on the comparison between the stellar spectrum filtered through theatmosphere and the unadulterated spectrum from the occulted stellar region. Thedisk-integrated spectrum is often used as a proxy for the occulted spectrum,yet they differ along the transit chord depending on stellar type androtational velocity. This is refereed to as the Rossiter-McLaughlin (RM)effect, which is known to bias transmission spectra at high spectral resolutionwhen calculated with the disk-integrated stellar spectrum. Recently, it wasshown that the first claimed atmospheric signal from an exoplanet cannot arisefrom absorption in the core of the sodium doublet, because the featuresobserved at high resolution are well reproduced by the RM effect. However, itremains unclear as to whether the detection made at medium spectral resolutionwith the HST arises from the smoothed RM signature or from the wings of theplanetary absorption line. More generally, the impact of the RM effect atmedium and low spectral resolution remains poorly explored. To address thisquestion, we simulated realistic transmission spectra in a variety of systemsusing the EVaporating Exoplanets code. We find that the RM effect should notbias broadband atmospheric features, such as hazes or molecular absorption,measured with the JWST/NIRSPEC (prism mode) at low resolution. However,absorption signatures from metastable helium or sodium measured at mediumresolution with the JWST/NIRSPEC (G140H mode) or HST/STIS can be biased,especially for planets on misaligned orbits across fast rotators. In contrast,we show that the Na signature originally reported in HD209458b, an alignedsystem, cannot be explained by the RM effect, supporting a planetary origin.

The Rossiter-McLaughlin effect and exoplanet transits: A delicate association at medium and low spectral resolution