Why use MSG?
Synthesizing stellar spectra from first principles is a complicated endeavor, requiring a detailed understanding of radiative transfer and atomic physics, together with significant computational resources. Therefore, in most circumstances its better to use one of the many pre-calculated grids of spectra published in the astrophysical literature (see, e.g., Lanz & Hubeny, 2003; Lanz & Hubeny, 2007; Kirby, 2011; de Laverny et al., 2012; Husser et al., 2013; Allende Prieto et al., 2018; Chiavassa et al., 2018; Zsargó et al., 2020). However, even with these grids a significant obstacle remains: when photospheric parameters fall between the grid nodes, some kind of interpolation is necessary in order to evaluate a spectrum.
MSG is designed to solve this problem. It’s not the first software package that offers stellar spectral interpolation (see, e.g., FERRE, Starfish and stsynphot); however, with spectral interpolation as its sole focus, it offers a combination of features unmatched by other packages:
scalability — MSG handles grids that are much larger (on disk) than available computer memory.
extensibility — MSG handles grids with an arbitrary number of dimensions.
portability — MSG is platform-agnostic and provide APIs for the programming languages (Fortran, C, Python) most commonly used in Astronomy.
performance — MSG provides smooth and accurate interpolates with minimal computational cost.
robustness — MSG gracefully handles missing data caused by holes and/or ragged boundaries in the grid.
Together, these features mean that MSG is flexible and powerful while remaining straightforward to use: it’s the perfect condiment to add flavor to your science!.
If you use MSG in your research, please cite the following papers:
Townsend Rich, Lopez Aaron, 2022, Journal of Open-Source Software, 8(81), 4602, https://doi.org/10.21105/joss.04
MSG remains under active development by the following team:
MSG has been developed with financial support from the following grants:
NSF awards ACI-1663696 and AST-1716436;
NASA award 80NSSC20K0515.