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"0mr" means 0 mrad rotation. "30mr" means 30 mrad rotation. On Tue, 26 Nov 2013, Kyle McCarty wrote: > Hello hps-software, > > I have been examining the background rates for the 2.2 GeV data. It appears > that the beam is not hitting at the correct spot, but is pushed too far to > the electron side. To show this, I have included two background rate plots > from the 6.6 GeV data (which appears correct; see > "CalorimeterHits_0100_6pt6. > pdf") versus the 2.2 GeV data (which appears offset; see > "CalorimeterHits_0100_2pt2.pdf"). > > To determine what caused this, I first examined the detector and the path > the particles take going through it. I fired photons, electrons, and > positrons through the detector (I used the 2.2 GeV V4 detector, since the > V5 is still a working version) at 30.5 mrad. All the particles appeared to > go where they should, so the detector geometry does not appear to be at > fault. > > To test the input data, I took a background StdHEP file (I used > "egs_2.2gev_0.00125x0_200na_ > 1mb_0mr_10.stdhep") and extracted the momentum of each particle from it and > plotted a histogram of px/pz (arctan(px/pz) should be the angle of the > beam). It appears that the distribution is a more-or-less Gaussian curve > centered around 0 radians with some extra noise at the bottom (probably > scattered particles). I included the photon plot (with Gaussian). From my > understanding, the input beam should be angled at 30.5 mrad. Also of note, > performing the same analysis on a 6.6 GeV background file results in the > Gaussian being centered around the expected 30.5 mrad angle. I have also > included the photon plot for this. Is there a way to tell SLIC to rotate > the 2.2 GeV background input, or am I using the wrong file? > > I was unable to check the LCSim output to see if this same distribution > occurs there, however, because I am unsure how to loop over an LCIO file > programmatically in JAS3. Is there a way, using JAS3's script interface, to > load an LCIO file as an ITuple so that it can be looped over, or can JAS3 > only open them to look through manually? > > Thanks, > > Kyle > > ######################################################################## > Use REPLY-ALL to reply to list > > To unsubscribe from the HPS-SOFTWARE list, click the following link: > https://listserv.slac.stanford.edu/cgi-bin/wa?SUBED1=HPS-SOFTWARE&A=1 > ######################################################################## Use REPLY-ALL to reply to list To unsubscribe from the HPS-SOFTWARE list, click the following link: https://listserv.slac.stanford.edu/cgi-bin/wa?SUBED1=HPS-SOFTWARE&A=1