Beam Simulations
From GlueXWiki
PS+TPOL simulations with 75 micron converter
- 75um beryllium converter
- photon beam energy 8.0 - 8.8 GeV.
- coherent bremsstrahlung spectrum, edge at 8.8 GeV.
- GlueX beamline geometry, 5mm collimator, 60um diamond radiator.
- 11.6 GeV electron beam @ 150 nA, 5e-8 m.rad emittance, 0.5mm virtual spot r.m.s.
- 100% PERP polarization on every beam photon, otherwise GlueX beam properties.
- tagger simulation with randoms included over interval [-10, +10]ns.
- background photons included from 1 MeV to endpoint energy.
- sufficient statistics to cut on variables to study systematics:
- A vs photon energy
- A vs photon displacement at converter
- A vs pair energy asymmetry, PS edge effects
- rough estimate of statistics:
- total events generated: 10,000 M
- total events with PS trigger: 3,100 M
- total PS triggers with in-time TPOL hits: 12 M
- total events passing TPOL analysis cuts: ~2 M (?)
- uncertainty on extracted A: 0.1% abs., 0.5% rel.
- time estimate: 100khr running on OSG
PS+TPOL simulations with 750 micron converter
- 750um beryllium converter
- photon beam energy 8.0 - 8.8 GeV.
- coherent bremsstrahlung spectrum, edge at 8.8 GeV.
- GlueX beamline geometry, 5mm collimator, 60um diamond radiator.
- 11.6 GeV electron beam @ 150 nA, 5e-8 m.rad emittance, 0.5mm virtual spot r.m.s.
- 100% PERP polarization on every beam photon, otherwise GlueX beam properties.
- tagger simulation with randoms included over interval [-10, +10]ns.
- background photons included from 1 MeV to endpoint energy.
- sufficient statistics to cut on variables to study systematics:
- A vs photon energy
- A vs photon displacement at converter
- A vs pair energy asymmetry, PS edge effects
- rough estimate of statistics:
- total events generated: 10,000 M
- total events with PS trigger: 3,100 M
- total PS triggers with in-time TPOL hits: 20 M
- total events passing TPOL analysis cuts: ~2 M (?)
- time estimate: 100khr running on OSG
- uncertainty on extracted A: 0.1% abs., 1% rel.
