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Integral Field Spectrographs (IFS) often require non-trivial calibrationtechniques to process raw data. The OH Suppressing InfraRed ImagingSpectrograph (OSIRIS) at the W. M. Keck Observatory is a lenslet-based IFS thatrequires precise methods to associate the flux on the detector with both awavelength and a position on the detector. During calibration scans, a singlecolumn lenslet mask is utilized to keep light from adjacent lenslet columnsseparate from the primary lenslet column, in order to uniquely determinespectral response of individual lenslets on the detector. Despite employing asingle column lenslet mask, an issue associated with such calibration schemesmay occur when light from adjacent masked lenslet columns leaks into theprimary lenslet column. Incorrectly characterizing the flux due to additionallight in the primary lenslet column results in one form of crosstalk betweenlenslet columns, which most clearly manifest as non-physical artifacts in thespectral dimension of the reduced data. We treat the problem of potentiallyblended calibration scans as a source separation problem and implementNon-negative Matrix Factorization (NMF) as a way to separate blendedcalibration scan spectra. After applying NMF to calibration scan data,extracted spectra from calibration scans show reduced crosstalk of up to26.7$\pm$0.5$\%$ while not adversely impacting the signal-to-noise ratio.Additionally, we determined the optimal number of calibration scans per lensletcolumn needed to create NMF factors, finding that greatest reduction crosstalkoccurs when NMF factors are created using one calibration scan per lensletcolumn.

Using Non-Negative Matrix Factorization to Improve Calibration of the Keck OSIRIS Integral Field Spectrograph