Box-fitting Least Squares (BLS) algorithms1 are particularly effective to analyze stellar photometric time series in search for periodic transits by exoplanets.  They search for signals characterized by a periodic alternation between two discrete levels, with much less time spent at the lower level. EEBLS (Edge Enhanced Box-fitting Least Squares) is an extension to BLS, that takes into account edge effects during exoplanet transits, as suggested by Dr. Peter McCullough (STScI). 

Peranso allows calculating and visualizing the EEBLS frequency spectrum, folding of the time series over the most dominant EEBLS period, calculating the epoch of mid-transit events, the transit depth and duration, etc. In addition, Peranso graphically displays the fit obtained by the EEBLS method.  

A full introduction to the EEBLS method is provided in Tutorial 6. Prominent periods of the Period Window appear as peaks.


(1) Kovacs G., Zucker S., Mazeh T., A box-fitting algorithm in the search for periodic transits, A&A, 2002.