<html><head><meta http-equiv="Content-Type" content="text/html charset=us-ascii"></head><body style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space;" class=""><div class="">Hi all,</div><div class=""><br class=""></div><div class="">The measured attenuation length should be used in the simulation and in the MC reconstruction. The average of what is measured is 525 cm. <a href="https://logbooks.jlab.org/entry/3316347" class="">https://logbooks.jlab.org/entry/3316347</a></div><div class=""><br class=""></div><div class="">
Best,<br class="">Mark Macrae Dalton<br class=""><br class="">--<br class="">Staff Scientist, Jefferson Lab<br class="">office: +1 757 269 6931<br class="">mobile: +1 757 849 2929<br class="">
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<br class=""><div><blockquote type="cite" class=""><div class="">On Jun 4, 2015, at 7:31 PM, <a href="mailto:wmcginle@andrew.cmu.edu" class="">wmcginle@andrew.cmu.edu</a> wrote:</div><br class="Apple-interchange-newline"><div class="">Hi all,<br class=""><br class="">Some time ago Alex Somov was simulating a photon gun at different angles<br class="">and noticed the bcal cluster energy mean was a function of thrown angle<br class="">and Sean made a fix so that the reconstructed cluster energy didn't depend<br class="">on the thrown angle. When that happened I changed the mc variation<br class="">attenuation lengths from 300 to 310 to set the cluster energy<br class="">distributions where we wanted them. I did not change it in the mc_parms,<br class="">sorry about that.<br class=""><br class="">Will<br class=""><br class=""><blockquote type="cite" class="">Hi all,<br class=""><br class="">I've analyzed some bggen data I made for a different study, and found<br class="">similar results to Tegan's [see attached BCAL_inv_mass-mc-cluster.pdf and<br class=""> BCAL_inv_mass-mc-shower.pdf]. An un-expert look at the reconstruction<br class="">code suggests that the attenuation lengths are used in the energy<br class="">reconstruction and these are indeed different for data and MC.<br class=""><br class="">There might be a mismatch in the values of the attenuation lengths used in<br class="">the simulation, and reconstruction, though. When I look at BCAL/mc_parms,<br class="">I find the parameter ATTEN_LENGTH = 300. When I look at the mc variation<br class="">of BCAL/attenuation_parameters, I find the lengths for each channel are<br class="">set<br class="">to 310. Probably these should be set to the same value?<br class=""><br class="">Another discrepancy I noticed was that the efficiency in each layer<br class="">calculated with Elton's BCAL_Eff plugin was different for MC and data.<br class="">For<br class="">example:<br class="">- Data Run 2931 - bcal_hist_eff-run3185.png<br class="">- MC - bcal_hist_eff-mc.png<br class="">I'm not sure if the smaller efficiency in MC is related to problems<br class="">reconstructing certain BCAL points, or other issues with the clusterizer..<br class=""><br class="">Cheers,<br class="">Sean<br class=""><br class="">On Thu, Jun 4, 2015 at 2:47 PM beattite <<a href="mailto:beattite@uregina.ca" class="">beattite@uregina.ca</a>> wrote:<br class=""><br class=""><blockquote type="cite" class="">Hello.<br class=""><br class="">Here are the mcsmear comparison plots using the variation=mc variable.<br class="">There are two files. One is the mass spectra using cluster energies,<br class="">the other is using shower energies.<br class=""></blockquote>_______________________________________________<br class="">Halld-cal mailing list<br class=""><a href="mailto:Halld-cal@jlab.org" class="">Halld-cal@jlab.org</a><br class="">https://mailman.jlab.org/mailman/listinfo/halld-cal<br class=""></blockquote><br class=""><br class="">_______________________________________________<br class="">Halld-cal mailing list<br class=""><a href="mailto:Halld-cal@jlab.org" class="">Halld-cal@jlab.org</a><br class="">https://mailman.jlab.org/mailman/listinfo/halld-cal<br class=""></div></blockquote></div><br class=""></body></html>