<html><head><meta http-equiv="Content-Type" content="text/html charset=utf-8"></head><body style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space;" class="">That’s fine except the E_beam here should be the Energy of the photon, instead the constant (of the electron beam energy) that’s now used in the code. Did I get that wrong?<div class=""><br class=""></div><div class="">Lei</div><div class=""><br class=""><div apple-content-edited="true" class="">
<div class=""><div class=""><div class="">Lei Guo</div><div class="">Assistant Professor</div><div class="">Physics Department</div><div class="">Florida International University</div><div class="">Miami, FL</div></div><div class=""><br class=""></div><div class="">email: <a href="mailto:leguo@fiu.edu" class="">leguo@fiu.edu</a> or <a href="mailto:lguo@jlab.org" class="">lguo@jlab.org</a></div><div class="">Office:305-348-0234</div></div>
</div>
<br class=""><div><blockquote type="cite" class=""><div class="">On Feb 10, 2016, at 12:39 PM, Carlos Salgado <<a href="mailto:salgado@jlab.org" class="">salgado@jlab.org</a>> wrote:</div><br class="Apple-interchange-newline"><div class="">Hi<br class=""><br class="">Follow the discussion in last g12 meeting.<br class=""><br class="">The formula in the code for the variance of the photon bean energy is OK.<br class=""><br class="">The uncertainty in the energy of the photon is 0.001* E_beam (per NIM and Eugene P.) The hodos were built such that this is true (different widths)<br class=""><br class="">Then consider a counter of width (energy) "a" where the (assume) energy distribution is flat: then Variance = sigma^2 = 1/a* int^a_0 E^2 dE = a^2/3<br class=""><br class="">Therefore if we distribute the uncertainty over a counter (energy bin) the variance is : sigma^2 = (0.001*E_beam)**2/3<br class=""><br class="">=Carlos<br class="">_______________________________________________<br class="">G12 mailing list<br class=""><a href="mailto:G12@jlab.org" class="">G12@jlab.org</a><br class="">https://mailman.jlab.org/mailman/listinfo/g12<br class=""></div></blockquote></div><br class=""></div></body></html>