Absolute cross section per reaction strip, for every declared channel. More...

#include <Rtypes.h>
#include <TString.h>
#include <map>
#include <utility>
#include <vector>

Include dependency graph for CrossSection.hpp:

Classes
class	CrossSection
	Computes and reports the absolute cross sections. More...

Detailed Description

Absolute cross section per reaction strip, for every declared channel.

A read-only pass over the scatter cache and the region cuts, covering every channel in CrossSectionConfig::CHANNELS. For each channel and strip:

sigma = N_reac / (N_beam * n_gas * L_strip)

where N_reac is the number of reactions of that channel at that strip, and N_beam the number of beam particles that reached it under every cut a reaction there also had to pass — so those cuts cancel in the ratio rather than needing their own efficiency.

N_reac comes from one of two places:

When the tag-efficiency store holds a record for the channel and strip, it is that record's count, unfolded by its efficiency and by the migration from the strip before. See TagEfficiency.hpp for the contract.
Otherwise it is the count the mixture fit attributed to the reaction component, uncorrected, with the fit-versus-core disagreement taken as the region systematic.

Beam energies come from the simulated unreacted beam, calibrated against the measured per-strip energy loss, so each strip's centre-of-mass energy is the simulation's rather than a nominal dE/dx table's — see BeamEnergies. Each channel's TALYS curve is the sum of the residual channels its exit list names, and its shape sets that channel's effective energies.

Definition in file CrossSection.hpp.

Classes

Detailed Description