A Measurement of the Water Abundance in the Atmosphere of the Hot Jupiter WASP-43b with High-resolution Cross-correlation Spectroscopy

Abstract

Measuring the abundances of carbon- and oxygen-bearing molecules has been a primary focus in studying the atmospheres of hot Jupiters, as doing so can help constrain the carbon-to-oxygen (C/O) ratio. The C/O ratio can help reveal the evolution and formation pathways of hot Jupiters and provide a strong understanding of the atmospheric composition. In the last decade, high-resolution spectral analyses have become increasingly useful in measuring precise abundances of several carbon- and oxygen-bearing molecules. This allows for a more precise constraint of the C/O ratio. We present four transits of the hot Jupiter WASP-43b observed between 1.45 $-$ 2.45 $\mu$m with the high-resolution Immersion GRating InfraRed Spectrometer (IGRINS) on the Gemini-S telescope. We detected H${}_2$O at a signal-to-noise ratio (SNR) of 3.51. We tested for the presence of CH${}_4$, CO, and CO${}_2$, but we did not detect these carbon-bearing species. We ran a retrieval for all four molecules and obtained a water abundance of ${\log }_{10}({\text{H}}_2\text{O})=-2.24_{-0.48}^{+0.57}$. We obtained an upper limit on the C/O ratio of C/O $<$ 0.95. These findings are consistent with previous observations from the Hubble Space Telescope and the James Webb Space Telescope.

11 pages, 6 figures

References in corpus (12)

• A Precise Water Abundance Measurement for the Hot Jupiter WASP-43b
• The imprint of exoplanet formation history on observable present-day spectra of hot Jupiters
• Mass-Metallicity Trends in Transiting Exoplanets from Atmospheric Abundances of H${}_2$O, Na, and K
• ExoMol line lists -- XXXIX. Ro-vibrational molecular line list for CO${}_2$
• A solar C/O and sub-solar metallicity in a hot Jupiter atmosphere
• Spitzer Phase Curve Constraints for WASP-43b at 3.6 and 4.5 microns
• ESPRESSO high resolution transmission spectroscopy of WASP-76b
• How drifting and evaporating pebbles shape giant planets II: Volatiles and refractories in atmospheres
• HyDRA-H: Simultaneous Hybrid Retrieval of Exoplanetary Emission Spectra
• Robustness Measures for Molecular Detections using High-Resolution Transmission Spectroscopy of Exoplanets
• ACCESS: A Visual to Near-infrared Spectrum of the Hot Jupiter WASP-43b with Evidence of ${\mathrm{H}}_2\mathrm{O}$, but no evidence of Na or K
• Retrieval of the dayside atmosphere of WASP-43b with CRIRES+