Bibliographic Details
| Title: |
HELIOS-K 2.0 Opacity Calculator and Open-source Opacity Database for Exoplanetary Atmospheres |
| Authors: |
Grimm, Simon L., Malik, Matej, Kitzmann, Daniel, Guzmán-Mesa, Andrea, Hoeijmakers, H. Jens, Fisher, Chloe, Mendonça, João M., Yurchenko, Sergey N., Tennyson, Jonathan, Alesina, Fabien, Buchschacher, Nicolas, Burnier, Julien, Segransan, Damien, Kurucz, Robert L., Heng, Kevin |
| Publication Year: |
2021 |
| Collection: |
Astrophysics |
| Subject Terms: |
Astrophysics - Earth and Planetary Astrophysics, Astrophysics - Instrumentation and Methods for Astrophysics |
| More Details: |
Computing and using opacities is a key part of modeling and interpreting data of exoplanetary atmospheres. Since the underlying spectroscopic line lists are constantly expanding and currently include up to ~ 10^10 - 10^11 transition lines, the opacity calculator codes need to become more powerful. Here we present major upgrades to the HELIOS-K GPU-accelerated opacity calculator and describe the necessary steps to process large line lists within a reasonable amount of time. Besides performance improvements, we include more capabilities and present a toolbox for handling different atomic and molecular data sets: from downloading and pre-processing the data to performing the opacity calculations in a user-friendly way. HELIOS-K supports line lists from ExoMol, HITRAN, HITEMP, NIST, Kurucz and VALD3. By matching the resolution of 0.1 cm^-1 and cutting length of 25 cm^-1 used by the ExoCross code for timing performance (251 seconds excluding data read-in time), HELIOS-K can process the ExoMol BT2 water line list in 12.5 seconds. Using a resolution of 0.01 cm^-1, it takes 45 seconds - equivalent to about 10^7 lines per second. As a wavenumber resolution of 0.01 cm^-1 suffices for most exoplanetary atmosphere spectroscopic calculations, we adopt this resolution in calculating opacity functions for several hundred atomic and molecular species, and make them freely available on the open-access DACE database. For the opacity calculations of the database, we use a cutting length of 100 cm^-1 for molecules and no cutting length for atoms. Our opacities are available for downloading from https://dace.unige.ch/opacityDatabase and may be visualized using https://dace.unige.ch/opacity.
Comment: Published in The Astrophysical Journal Supplement Series |
| Document Type: |
Working Paper |
| DOI: |
10.3847/1538-4365/abd773 |
| Access URL: |
http://arxiv.org/abs/2101.02005 |
| Accession Number: |
edsarx.2101.02005 |
| Database: |
arXiv |
