Search For Laser Emission Lines with the APF

My project is a search for laser emission lines with the Automated Planet Finder that could be communication from extraterrestrial intelligence. Optical lasers are promising interstellar communication tools, as they offer both high intensity and privacy. I search through 5,866 APF stellar spectra corresponding to 852 stars, identifying all the potential laser signal candidates. I first identify all the pixels above a certain threshold, then fit a Gaussian to each of the detections, and then determine the FWHM of the signal. If the detection is above the threshold, Gaussian-like, and wider than the PSF of the telescope, the signal moves onto the next step in verifying it as an extraterrestrial laser emission line. I identify a total of 45,756 detections in the APF data.