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A small, fast, interactive viewer for SPS spectra, using Non-negative Matrix Factorisation (NMF) and bilinear interpolation for reconstruction.

Sengi is being actively developed on github. If you find any bugs, or wish to make a feature request, please submit an issue.

Health Warning

Because of the nature of the NMF reconstruction the spectra generated by Sengi will not be exact. We show in the associated paper that the accuracy is sufficient for prototyping and education purposes, however for science purposes the original models should always be used.

If you use Sengi as part of your project, we would appreciate if you cite the associated paper:
       author = {{Lovell}, Christopher C.},
        title = "{Sengi: a small, fast, interactive 
                viewer for spectral outputs from stellar 
                population synthesis models}",
      journal = {arXiv e-prints},
     keywords = {Astrophysics - Instrumentation and Methods 
     for Astrophysics, Astrophysics - Astrophysics of Galaxies},
         year = "2019",
        month = "Nov",
          eid = {arXiv:1911.12713},
        pages = {arXiv:1911.12713},
archivePrefix = {arXiv},
       eprint = {1911.12713},
 primaryClass = {astro-ph.IM},
       adsurl = {https://ui.adsabs.harvard.edu/abs/2019arXiv191112713L},
      adsnote = {Provided by the SAO/NASA Astrophysics Data System}


We would like to thank all of the SPS owners for permission to use their models.


IMF: Initial Mass Function

SPS: Stellar Population Synthesis

SSP: Simple Stellar Population

NMF: Non-negative Matrix Factorisation

PCA: Principal Component Analysis