arXiv subjects

Antonín Knížek

Publications and source records attributed to Antonín Knížek.

2 recordsLinked to original sources

arXiv2025

Data availability and requirements relevant for the Ariel space mission and other exoplanet atmosphere applications

The goal of this white paper is to provide a snapshot of the data availability and data needs primarily for the Ariel space mission, but also for related atmospheric studies of exoplanets and brown dwarfs. It covers the following data-related topics: molecular and atomic line lists, line profiles, computed cross-sections and opacities, collision-induced absorption and other continuum data, optical properties of aerosols and surfaces, atmospheric chemistry, UV photodissociation and photoabsorption cross-sections, and standards in the description and format of such data. These data aspects are discussed by addressing the following questions for each topic, based on the experience of the "data-provider" and "data-user" communities: (1) what are the types and sources of currently available data, (2) what work is currently in progress, and (3) what are the current and anticipated data needs. We present a GitHub platform for Ariel-related data, with the goal to provide a go-to place for both data-users and data-providers, for the users to make requests for their data needs and for the data-providers to link to their available data. Our aim throughout the paper is to provide practical information on existing sources of data whether in databases, theoretical, or literature sources.

astro-ph.IM↗

arXiv2025

A Full-Atmosphere Model of Jupiter

This paper presents a combined 1D photochemical-thermochemical kinetics model of Jupiter's deeper atmosphere, troposphere and stratosphere. The model covers atmospheric pressure range from $1.1 \times 10^{3}$ bar to $7.4 \times 10^{-11}$ bar and is the first model that incorporates sulfur chemistry when spanning an atmospheric region of this extent. This model incorporates a new version of the STAND reaction network with updated NH4SH chemistry, and updated Antoine equation parameters for NH4SH and H2S. Validation against current models of Jupiter's atmosphere as well as recent observational data shows that our model successfully describes Jupiter's main observed chemical features. Since one of the focuses of the model is the chemistry on nitrogen, it correctly predicts the formation of a mixed NH3-NH4SH cloud layer between 0.1 and 1 bar. It also describes the chemistry of HCN throughout the atmosphere and discovers a region in the stratosphere between $1 \times 10^{-6}$ and $6.76 \times 10^{-8}$ bar, where HCN forms through radical chemistry with maximum mixing ratio 33 ppb at $2.94 \times 10^{-7}$ bar -- a prediction testable by observations. At the same time, our model predicts a quenched N2 mixing ratio 490 ppm up to 10$^{-6}$ bar. The model therefore successfully bridges the gap between existing models of separate regions of Jupiter's atmosphere and makes new testable predictions of several chemical species.

astro-ph.EP↗