Qweak Inelastic FFTfile PMTLED

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An attempt to use Richard Jones' FFT algorithm on helicity.

Below is a histogram of an LED shining onto a PMT in Qweak. Notice the multiple peaks in the asymmetry distribution.

11498 000 PMTLedAsymBefore.png


Using Richard's FFT code File:FFTseries.cc RJ.txt

and the root commands

.L FFTseries.cc 
TH1* fft=FFTseries(Mps_Tree,"qwk_pmtled","hw_sum");

11498 000 PMTLedAsymFFT.png


The following frequencies appear : 10,60,120,180, 240, 300