From 54da09d3ec8266a5e8b95842951ddb0a67c26255 Mon Sep 17 00:00:00 2001 From: tlatorre Date: Thu, 18 Oct 2018 09:44:23 -0500 Subject: update theta0 calculation to use the radiation length in light water Previously I was using the radiation length in light water but scaling it by the density of heavy water, which isn't correct. Since the radiation length in heavy and light water is almost identical, we just use the radiation length in light water. --- src/pdg.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) (limited to 'src/pdg.c') diff --git a/src/pdg.c b/src/pdg.c index 780fbc8..a3eb2d5 100644 --- a/src/pdg.c +++ b/src/pdg.c @@ -1,7 +1,8 @@ #include "pdg.h" #include "math.h" +#include "sno.h" -double get_scattering_rms(double x, double p, double beta, double z, double rho) +double get_scattering_rms(double x, double p, double beta, double z) { /* Returns the RMS width of the scattering angle for a particle deflected * by many small-angle scatters after a distance `x`. `p` is the momentum @@ -22,5 +23,5 @@ double get_scattering_rms(double x, double p, double beta, double z, double rho) * See Equation 33.15 in * http://pdg.lbl.gov/2018/reviews/rpp2018-rev-passage-particles-matter.pdf. */ if (x == 0.0) return 0.0; - return (13.6/(beta*p))*z*sqrt(x*rho/RADIATION_LENGTH)*(1+0.038*log((x*z*z)/(RADIATION_LENGTH*beta*beta/rho))); + return (13.6/(beta*p))*z*sqrt(x*WATER_DENSITY/RADIATION_LENGTH)*(1+0.038*log((x*z*z)/(RADIATION_LENGTH*beta*beta/WATER_DENSITY))); } -- cgit