A package to read SPARC data to extract Galactic Rotation Curves
By Aman Desai
Galaxy rotation curves are a class of plots which have velocity of the galactic objects on the y-axis and the x-axis represents their radial distances from the galactic center. The experimental data indicates flatness of the curve which is inconsistent with theoretical predictions. This inconsistency has found its explanation with the hypothesis that there is presence of Dark Matter halos. However, there also exists a set of alternative theories such as the Modified Newtonian Dynamics (MOND) which take a different approach to explanation viz. by modifying the Newtonian laws when the acceleration is less than a minimum threshold. The aforementioned models have parameters, some of which can be extracted from observation or other indirect techniques, while few of them are free parameters. Using these free parameters as an input to statistical fitting package, one can fit data with models. While this procedure is well-defined, it may still be inaccessible to undergraduates owing to the use of advanced fitting packages and different data formats. To streamline this procedure of reading astronomical SPARC data in a simple way as well as fitting (new) models with data we present the pygrc package Link. The package comes with an example notebook showcasing a use case.