HELIOS-K 2.0 Opacity Calculator and Open-source Opacity Database for Exoplanetary Atmospheres

Abstract

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.

Published in The Astrophysical Journal Supplement Series

References in corpus (41)

• A high accuracy computed water line list
• ExoMol molecular line lists XXX: a complete high-accuracy line list for water
• The ExoMol database: molecular line lists for exoplanet and other hot atmospheres
• ExoMol line lists IV: The rotation-vibration spectrum of methane up to 1500 K
• A variationally computed line list for hot NH3
• Atomic and Molecular Opacities for Brown Dwarf and Giant Planet Atmospheres
• ExoMol line lists III: An improved hot rotation-vibration line list for HCN and HNC
• CH in stellar atmospheres: an extensive linelist
• ExoMol Molecular linelists -- XXXIII. The spectrum of Titanium Oxide
• The Near-Infrared and Optical Spectra of Methane Dwarfs and Brown Dwarfs
• Improved HCN/HNC linelist, model atmospheres and synthetic spectra for WZ Cas
• ExoMol molecular line lists - XVI: The rotation-vibration spectrum of hot H${}_2$S
• The 2020 release of the ExoMol database: molecular line lists for exoplanet and other hot atmospheres
• ExoMol line lists XVIII. The high temperature spectrum of VO
• HELIOS-K: An Ultrafast, Open-source Opacity Calculator for Radiative Transfer
• ExoCross: a general program for generating spectra from molecular line lists
• ExoMol molecular line lists - XIV: The rotation-vibration spectrum of hot SO${}_2$
• Calculations of the Far-Wing Line Profiles of Sodium and Potassium in the Atmospheres of Substellar-Mass Objects
• HELIOS: An Open-source, GPU-accelerated Radiative Transfer Code For Self-consistent Exoplanetary Atmospheres
• A hybrid line list for CH${}_4$ and hot methane continuum
• The ExoMolOP Database: Cross-sections and k-tables for Molecules of Interest in High-Temperature Exoplanet Atmospheres
• ExoMol line lists II: The ro-vibrational spectrum of SiO
• New study of the line profiles of sodium perturbed by H2
• Self-luminous and irradiated exoplanetary atmospheres explored with HELIOS
• ExoMol molecular line lists V: The ro-vibrational spectra of NaCl and KCl
• ExoMol molecular line lists -- XXXVII: spectra of acetylene
• ExoMol molecular line lists: IX The spectrum of AlO
• Temperature-dependent molecular absorption cross sections for exoplanets and other atmospheres
• Spectroscopic line parameters of NO, NO${}_2$, and N${}_2$O for the HITEMP database
• ExoMol molecular line lists - XXIII: spectra of PO and PS
• Hyperfine Splitting in the VALD Database of Spectral-line Parameters
• ExoMol line lists XXIV: A new hot line list for silicon monohydride, SiH
• ExoMol Line List XXI: Nitric Oxide (NO)
• ExoMol line lists XXVIII: The rovibronic spectrum of AlH
• Analyzing Atmospheric Temperature Profiles and Spectra of M dwarf Rocky Planets
• ExoMol molecular line lists XII: Line Lists for 8 isotopologues of CS
• Exomol molecular line lists VI: A high temperature line list for Phosphorus Nitride
• ExoMol line lists -- XXII. The rotation-vibration spectrum of silane up to 1200 K
• ExoMol molecular line lists - XVII The rotation-vibration spectrum of hot SO${}_3$
• ExoMol molecular line lists - XXVI: spectra of SH and NS
• ExoMol line lists XXV: A hot line list for silicon sulphide, SiS

Cited by in corpus (92)

• Early Release Science of the exoplanet WASP-39b with JWST NIRISS
• Identification of carbon dioxide in an exoplanet atmosphere
• A solar C/O and sub-solar metallicity in a hot Jupiter atmosphere
• A broadband thermal emission spectrum of the ultra-hot Jupiter WASP-18b
• Where is the Water? Jupiter-like C/H ratio but strong H${}_2$O depletion found on $\tau$ Boötis b using SPIRou
• A secondary atmosphere on the rocky exoplanet 55 Cancri e
• Titanium oxide and chemical inhomogeneity in the atmosphere of the exoplanet WASP-189b
• Retention of water in terrestrial magma oceans and carbon-rich early atmospheres
• An Atomic Spectral Survey of WASP-76b: Resolving Chemical Gradients and Asymmetries
• Sulphur dioxide in the mid-infrared transmission spectrum of WASP-39b
• Vanadium oxide and a sharp onset of cold-trapping on a giant exoplanet
• Awesome SOSS: Transmission Spectroscopy of WASP-96b with NIRISS/SOSS
• The Roasting Marshmallows Program with IGRINS on Gemini South I: Composition and Climate of the Ultra Hot Jupiter WASP-18 b
• EXOPLINES: Molecular Absorption Cross-Section Database for Brown Dwarf and Giant Exoplanet Atmospheres
• GJ 1252b: A Hot Terrestrial Super-Earth With No Atmosphere
• Non-local thermodynamic equilibrium effects determine the upper atmospheric temperature structure of the ultra-hot Jupiter KELT-9b
• Carbon monoxide emission lines reveal an inverted atmosphere in the ultra hot Jupiter WASP-33 b consistent with an eastward hot spot
• JWST transmission spectroscopy of HD 209458b: a super-solar metallicity, a very low C/O, and no evidence of CH4, HCN, or C2H2
• Simulating gas giant exoplanet atmospheres with Exo-FMS: Comparing semi-grey, picket fence and correlated-k radiative-transfer schemes
• Observability of Evaporating Lava Worlds
• Awesome SOSS: Atmospheric Characterisation of WASP-96 b using the JWST Early Release Observations
• 3D radiative-transfer for exoplanet atmospheres. gCMCRT: a GPU accelerated MCRT code
• CHEOPS geometric albedo of the hot Jupiter HD 209458b
• TOI-2109b: An Ultrahot Gas Giant on a 16 hr Orbit
• Confirmation of Iron Emission Lines and Non-detection of TiO on the Dayside of KELT-9b with MAROON-X
• CO or no CO? Narrowing the CO abundance constraint and recovering the H2O detection in the atmosphere of WASP-127 b using SPIRou
• The Detectability of Rocky Planet Surface and Atmosphere Composition with JWST: The Case of LHS 3844b
• Accreting protoplanets: Spectral signatures and magnitude of gas and dust extinction at H alpha
• CRIRES+ and ESPRESSO reveal an atmosphere enriched in volatiles relative to refractories on the ultra-hot Jupiter WASP-121b
• Mining the Ultra-Hot Skies of HAT-P-70b: Detection of a Profusion of Neutral and Ionized Species
• Astrometric Accelerations as Dynamical Beacons: Discovery and Characterization of HIP 21152 B, the First T-Dwarf Companion in the Hyades
• Retrieval Study of Brown Dwarfs Across the L-T Sequence
• JWST reveals a rapid and strong day side variability of 55 Cancri e
• The PEPSI Exoplanet Transit Survey (PETS) I: Investigating the presence of a silicate atmosphere on the super-Earth 55 Cnc e
• Hot Rocks Survey I : A possible shallow eclipse for LHS 1478 b
• Auto-Differentiable Spectrum Model for High-Dispersion Characterization of Exoplanets and Brown Dwarfs
• Low-Temperature Gas Opacities with AESOPUS 2.0
• Exoplanet atmospheres at high resolution through a modest-size telescope. Fe II in MASCARA-2b and KELT-9b with FIES on the Nordic Optical Telescope
• ExoMol line lists -- XLV. Rovibronic molecular line lists of calcium monohydride (CaH) and magnesium monohydride (MgH)
• Unifying High- and Low-resolution Observations to Constrain the Dayside Atmosphere of KELT-20b/MASCARA-2b
• Ground-based Optical Transmission Spectroscopy of the Nearby Terrestrial Exoplanet LTT 1445Ab
• High-Resolution Transmission Spectroscopy of the Terrestrial Exoplanet GJ 486b
• Data availability and requirements relevant for the Ariel space mission and other exoplanet atmosphere applications
• Diagnosing limb asymmetries in hot and ultra-hot Jupiters with high-resolution transmission spectroscopy
• Observability of silicates in volatile atmospheres of super-Earths and sub-Neptunes
• An atlas of resolved spectral features in the transmission spectrum of WASP-189 b with MAROON-X
• Role of magma oceans in controlling carbon and oxygen of sub-Neptune atmospheres
• Hot Rocks Survey II: The thermal emission of TOI-1468 b reveals a hot bare rock
• Where are the Water Worlds?: Self-Consistent Models of Water-Rich Exoplanet Atmospheres
• Transmission spectroscopy of the lowest-density gas giant: metals and a potential extended outflow in HAT-P-67b
• Atmospheric C/O Ratios of Sub-Neptunes with Magma Oceans: Homemade rather than Inherited
• The Mantis Network I: A standard grid of templates and masks for cross-correlation analyses of ultra-hot Jupiter transmission spectra
• The THOR+HELIOS general circulation model: multi-wavelength radiative transfer with accurate scattering by clouds/hazes
• Convective shutdown in the atmospheres of lava worlds
• GCM Constraints on the Detectability of the CO${}_2$-CH${}_4$ Biosignature Pair on TRAPPIST-1e with JWST
• Cloud-convection feedback in brown dwarfs atmosphere
• PyExoCross: a Python program for generating spectra and cross-sections from molecular line lists
• Searching for NLTE effects in the high-resolution transmission spectrum of WASP-121 b with Cloudy for Exoplanets
• Magma ocean interactions can explain JWST observations of the sub-Neptune TOI-270 d
• EOS-ESTM: A flexible climate model for habitable exoplanets
• Evolution of steam worlds: energetic aspects
• The energetic particle environment of a GJ 436 b-like planet
• Competing chemical signatures in the atmosphere of TOI-270 d: Inference of sulfur and carbon chemistry
• Silicate Precursor Silane detected in Cold Low-Metallicity Brown Dwarf
• Cross-sections for heavy atmospheres: H${}_2$O self-broadening
• How do we optimally sample model grids of exoplanet spectra?
• Multi-epoch detections of the extended atmosphere and transmission spectra of KELT-9b with a 1.5 m telescope
• Self-limited tidal heating and prolonged magma oceans in the L 98-59 system
• Detection of faculae in the transit and transmission spectrum of WASP-69b
• IGRINS observations of WASP-127 b: H${}_2$O, CO, and super-Solar atmospheric metallicity in the inflated sub-Saturn
• Characterising the Atmosphere of 55 Cancri e: 1D Forward Model Grid for Current and Future JWST Observations
• The impact of spectral line wing cut-off: Recommended standard method with application to MAESTRO opacity database
• EOS: Atmospheric Radiative Transfer in Habitable Worlds with HELIOS
• Cthulhu: An Open Source Molecular and Atomic Cross Section Computation Code for Substellar Atmospheres
• Hydride ion continuum hides absorption signatures in the NIRPS near-infrared transmission spectrum of the ultra-hot gas giant WASP-189b
• Conditions for radiative zones in the molecular hydrogen envelope of Jupiter and Saturn: The role of alkali metals
• Possible Evidence for the Presence of Volatiles on the Warm Super-Earth TOI-270 b
• Near-instantaneous Atmospheric Retrievals and Model Comparison with FASTER
• Coupled Thermal-Chemical Evolution Models of Sub-Neptunes Reveal Atmospheric Signatures of Their Formation Location
• A Disintegrating Rocky World Shrouded in Dust and Gas: Mid-IR Observations of K2-22b using JWST
• Spitzer phase curve observations and circulation models of the inflated ultra-hot Jupiter WASP-76b
• Evidence for an Atmosphere on the Ultra-Short Period super-Earth HD 3167 b
• RAPOC : the Rosseland and Planck opacity converter. A user-friendly and fast opacity program for Python
• A grid of self-consistent MSG (MARCS-StaticWeather-GGchem) cool stellar, sub-stellar, and exoplanetary model atmospheres
• Patchy nightside clouds on ultra-hot Jupiters: General Circulation Model simulations with radiatively active cloud tracers
• The Effect of Atmospheric Chemistry on the Optical Geometric Albedos of Hot Jupiters
• Hot Rocks Survey V: Secondary Eclipse Photometry of GJ 3473 b with JWST/MIRI
• Sensitivity of Dry Lava Planet Atmospheric Emission Spectra to Changes in Lava Compositions
• Chemical diversity of the atmospheres and interiors of sub-Neptunes: a case study of GJ 436 b
• Grain Growth in Escaping Atmospheres: Implications for the Radius Inflation of Super-Puffs
• TOI-1518b: A Misaligned Ultra-hot Jupiter with Iron in its Atmosphere
• The breaking of cold traps and onset of titanium in ultra-hot Jupiter atmospheres: WASP-189b in context