LaRT | Kwang-Il Seon's Home Page

Kwang-Il Seon's Home Page

The first principle is that you must not fool yourself. - Richard Feyman

LaRT (Lyman-alpha Radiative Transfer)

LaRT is a cell-based, 3D Monte-Carlo RT code for the Lyɑ radiation.

The code is written in modern fortran and has been developed to study Lyɑ RT and the Wouthuysen-Field effect. LaRT can also calculate polarization by completely considering the fine-structure of neutral hydrogen without arbitrarily dividing core and wing regimes.

A keynote presented in Vietnam is available for download (click here).

Data

Basic RT data: Monte Carlo Simulation of the WF effect (Seon & Kim, 2020, ApJS 250, 9)

Download the Galaxy Models: LaRT models for a LAEs (Song et al., 2020, ApJ, 901, 41)

Polarization: Seon et al. (2022, ApJS, 259, 3)

Code

LaRT is publicly available via https://github.com/seoncafe/LaRT and

https://doi.org/10.5281/zenodo.5618511.

Please feel free to contact me if you need help or want to use it for the exoplanet atmosphere.

Movie

The first movie demonstrates the polarization result obtained with LaRT. Lyɑ RT was performed for a cubic shape medium viewed at the (1, 1, 1)-direction. The left plot shows the spectrum, the middle and right panels show a variation of the intensity and polarization pattern, respectively, as frequency x varies. (Click to play the movie.)

The second movie demonstrates the Lyɑ transit simulation obtained with LaRT. Lyɑ photons from a star are incident upon the planetary atmosphere, which has been evaporated by the XUV radiation field from the star. The left panel shows the Lyɑ brightness, and the right panel shows the variation of Lyɑ spectrum. The black dot represents the planet, while the evaporated atmosphere is depicted in purple.