Paper

RUBIS: a simple tool for calculating the centrifugal deformation of stars and planets

Houdayer, Pierre S, Reese, Daniel R

2023

Overview

We present RUBIS (Rotation code Using Barotropy conservation over Isopotential Surfaces), a fully Python-based centrifugal deformation program available at https://github.com/pierrehoudayer/RUBIS. The code has been designed to calculate the centrifugal deformation of stars and planets resulting from a given cylindrical rotation profile, starting from a spherically symmetric non-rotating model. The underlying assumption in RUBIS is that the relationship between density and pressure is preserved during the deformation process. This leads to many procedural simplifications. For instance, RUBIS only needs to solve Poisson' equation, either in spheroidal or spherical coordinates depending on whether the 1D model has discontinuities or not. We present the benefits of using RUBIS to deform polytropic models and more complex barotropic structures, thus providing, to a certain extent, insights into baroclinic models. The resulting structures can be used for a wide range of applications, including the seismic study of models. Finally, we illustrate how RUBIS is beneficial specifically in the analysis of Jupiter's gravitational moments, thanks to its ability to handle discontinuous models while retaining a high accuracy compared to current methods.

• Publisher: Cornell University Library, arXiv.org
• Subject: Deformation / Density / Discontinuity / One dimensional models / Planetary rotation / Spherical coordinates