The ESO SupJup Survey

Springer Link (Chiba Institute of Technology)

Abstract

Context. Recent research suggests that the distinct formation processes of exoplanets and brown dwarfs may have an influence on the chemical and isotopic composition of their atmospheres. Variations in the carbon 12C/13C isotope ratio have been observed and tentatively linked to the top-down formation of brown dwarfs and the core accretion pathway of super-Jupiters. The ESO SupJup Survey, conducted with CRIRES+ on the Very Large Telescope, aims to characterise the atmospheres of young brown dwarfs and super-Jupiters, specifically by investigating the 12C/13C ratio as a tracer of their formation pathways. Aims. We present the atmospheric characterisation of three isolated L-type brown dwarfs (2MASS J08354256-0819237, 2MASS J05012406-0010452, and 2MASS J05002100+0330501) included in the ESO SupJup Survey. We aim to constrain the C/O and 12C/13C ratios, and investigate whether the oxygen 16O/18O isotope ratio can be probed. Methods. We analysed the CRIRES+ K-band spectra of the three targets using our atmospheric retrieval framework. This framework couples the radiative transfer code petitRADTRANS with the sampling algorithm MultiNest. Results. We report 12C/13C ratios of 89−11+11 and 117−17+20 for J0835 and J0500 with strong 13CO significance (>6.5σ) and a tentative (3σ) detection of 13CO for J0501, resulting in a carbon isotope ratio of 155−53+56. Only a weak detection of the H218O isotope was found in J0835. The C/O ratios are found to be in the range 0.65 to 0.71 for the three targets, and all exhibit strong detections of HF. Conclusions. The 12C/13C ratios appear to be higher than that of the interstellar medium.

Authors 11

1. W. Mulder Aachen Leiden Observatory

   Leiden University · Leiden Observatory

   Affiliation as printed

   Leiden Observatory , Leiden University , Einsteinweg 55 , 2333 CC Leiden , The Netherlands

2. S. de Regt Aachen Leiden Observatory

   Leiden University · Leiden Observatory

   Affiliation as printed

   Leiden Observatory , Leiden University , Einsteinweg 55 , 2333 CC Leiden , The Netherlands

3. R. Landman Aachen Leiden Observatory

   Leiden University · Leiden Observatory

   Affiliation as printed

   Leiden Observatory , Leiden University , Einsteinweg 55 , 2333 CC Leiden , The Netherlands

4. D. González Picos Aachen Leiden Observatory

   Leiden University · Leiden Observatory

   Affiliation as printed

   Leiden Observatory , Leiden University , Einsteinweg 55 , 2333 CC Leiden , The Netherlands

5. Ignas A. G. Snellen Aachen Leiden Observatory

   Leiden University · Leiden Observatory

   Affiliation as printed

   Leiden Observatory , Leiden University , Einsteinweg 55 , 2333 CC Leiden , The Netherlands

6. Y. P. Zhang Aachen Leiden Observatory

   Leiden University · California Institute of Technology · Leiden Observatory

   Affiliation as printed

   Department of Astronomy , California Institute of Technology , Pasadena , CA 91125 , USA

   Leiden Observatory , Leiden University , Einsteinweg 55 , 2333 CC Leiden , The Netherlands

7. Siddharth Gandhi

   University of Warwick · Institut für Palliative Care · Infrared Processing and Analysis Center

   Affiliation as printed

   Department of Physics , University of Warwick , Coventry CV4 7AL , UK

   IPAC , Mail Code 100-22 ,

8. C. Ginski

   University of Warwick

   Affiliation as printed

   Centre for Exoplanets and Habitability , University of Warwick , Gibbet Hill Road , Coventry CV4 7AL , UK

9. A. Y. Kesseli

   Institut für Palliative Care · Infrared Processing and Analysis Center

   Affiliation as printed

   IPAC , Mail Code 100-22 ,

10. E. Nasedkin

    California Institute of Technology · Ollscoil na Gaillimhe – University of Galway

    Affiliation as printed

    Caltech , 1200 E. California Boulevard , Pasadena , CA 91125 , USA

    School of Natural Sciences , Center for Astronomy , University of Galway , Galway , H91 CF50 , Ireland

11. T. Stolker Aachen Leiden Observatory

    Leiden University · Leiden Observatory

    Affiliation as printed

    Leiden Observatory , Leiden University , Einsteinweg 55 , 2333 CC Leiden , The Netherlands