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

The spectroscopy of faint planetary-mass companions to nearby stars is one ofthe main challenges that new-generation high-contrast spectro-imagers are goingto face. In a previous work we presented a long slit coronagraph (LSC), forwhich the presence of a slit in the coronagraphic focal plane induces a complexdistribution of energy in the Lyot pupil-plane that cannot be easily maskedwith a binary Lyot stop. To alleviate this concern, we propose to use a pupilapodization to suppress diffraction, creating an apodized long slit coronagraph(ALSC). After describing how the apodization is optimized, we demonstrate itsadvantages with respect to the CLC in the context of SPHERE/IRDIS long slitspectroscopy (LSS) mode at low-resolution with a 0.12" slit and 0.18"coronagraphic mask. We perform different sets of simulations with and withoutaberrations, and with and without a slit to demonstrate that the apodization isa more appropriate concept for LSS, at the expense of a significantly reducedthroughput (37%) compared to the LSC. Then we perform detailed end-to-endsimulations of the LSC and the ALSC that include realistic levels ofaberrations to obtain datasets representing 1h of integration time on stars ofspectral types A0 to M0 located at 10 pc. We insert spectra of planetarycompanions at different effective temperatures (Teff) and surface gravities(log g) into the data at angular separations of 0.3" to 1.5" and with contrastratios from 6 to 18 mag. Using the SD method to subtract the speckles, we showthat the ALSC brings a gain in sensitivity of up to 3 mag at 0.3" with respectto the LSC, which leads to a much better spectral extraction below 0.5". Interms of Teff, we demonstrate that at small angular separations the limit withthe ALSC is always lower by at least 100K, inducing an increase of sensitivityof a factor up to 1.8 in objects' masses at young ages. [Abridged]

Apodization in high-contrast long-slit spectroscopy. Closer, deeper, fainter, cooler