2020/12/28 by Luke Finnerty, Cam Buzard, Stefan Pelletier +6 · 1 citation
Chemistry · Physics and Astronomy · #Astronomy #Astrophysics #Epoch (astronomy) #Exoplanet #Hot Jupiter #Physics #Planet #Planetary system #Population #Spectroscopy #Spectroscopy and Chemometric Analyses #Spectroscopy and Laser Applications #Stars #Stellar, planetary, and galactic studies #astro-ph.EP
paper · pdf · doi:10.3847/1538-3881/abd6ec
22 pages, 8 figures, accepted to AJ
arxiv created 2020/12/28 · openalex publication_date 2021/02/04 · arxiv updated 2021/02/10 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
Abstract While high-resolution cross-correlation spectroscopy (HRCCS) techniques have proven effective at characterizing the atmospheres of transiting and nontransiting hot Jupiters, the limitations of these techniques are not well understood. We present a series of simulations of one HRCCS technique, which combines the cross-correlation functions from multiple epochs, to place temperature and contrast limits on the accessible exoplanet population for the first time. We find that planets approximately Saturn-sized and larger within ∼0.2 au of a Sun-like star are likely to be detectable with current instrumentation in the L band, a significant expansion compared with the previously studied population. Cooler ( T eq ≤ 1000 K) exoplanets are more detectable than suggested by their photometric contrast alone as a result of chemical changes that increase spectroscopic contrast. The L -band CH 4 spectrum of cooler exoplanets enables robust constraints on the atmospheric C/O ratio at T eq ∼ 900 K, which have proven difficult to obtain for hot Jupiters. These results suggest that the multi-epoch approach to HRCCS can detect and characterize exoplanet atmospheres throughout the inner regions of Sun-like systems with existing high-resolution spectrographs. We find that many epochs of modest signal-to-noise ratio (S/N epoch ∼ 1500) yield the clearest detections and constraints on C/O, emphasizing the need for high-precision near-infrared telluric correction with short integration times.