Solid Background
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Revision as of 15:25, 13 March 2012 by Riordan (Talk | contribs) (→PVDIS Geant4 modeled background from Target)
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PVDIS Geant4 modeled background from Target
Rates and flux from GEMC for PVDIS follow. Validation against GEANT3 can be found here: Compare_to_geant3_result.
Rates on GEMs for 50uA on LH2. Solid lines are unbaffled, dashed are with lead baffles:
Flux in EM calorimeter for 50uA on LH2. Solid lines are unbaffled, dashed are with lead baffles. The true rate should be taken from the black lines.
Single particle inclusive production (outdated)
Single particle inclusive production can be signal or background depends on what the studied physics is. But it always add into radiation dose taken by detectors.
How it has been done in the proposals
current study
approach
result of SIDIS for BaBar configuration
| eDIS Cut | eDIS NoCut | pi- Cut | pi- NoCut | pi+ Cut | pi+ NoCut | |
|---|---|---|---|---|---|---|
| rate at forward angle EC (Hz) | 63k | 63k | 4.9M | 11M | 5.7M | 13M |
| rate at large angle EC (Hz) | 3.3k | 19k | 9.6k | 20M | 9.1k | 24M |
| Energy Flux at forward angle EC (GeV/10cm2/s) | ||||||
| Energy Flux at large angle EC (GeV/10cm2/s) |
- note
- eDIS means DIS electron which require W>2GeV and Q2>1(GeV)^2
- the cut (E>0.9GeV for forward angle EC, E>3.5GeV for large angle EC) is to match SIDIS physics and trigger condition, refer to SIDIS rate estimation at page 48 of [1].
- When use the result with the cut to compare to SIDIS rate table in proposal, please note SIDIS has a correction factor 2 based on data comparison, refer to page 66 of [2]. So assume the correction is good for all pion calculated from Wiser, all numbers for pions in the table should divided by 2
result of PVDIS for BaBar configuration
| eDIS (Open) | pi- (Open) | pi+ (Open) | eDIS (baffled) | pi- (baffled) | pi+ (baffled) | |
|---|---|---|---|---|---|---|
| rate at forward angle EC (Hz) | 3M | 5775M | 11697M | 350k | 64M | 110M |
| Energy Flux at forward angle EC (GeV/10cm2/s) (total,peak) | 573, 25 | 4e5,1e4 | 7.6e5,2e4 | 120,6 | 6700,300 | 1663,100 |
- note
- eDIS means DIS electron which require W>2GeV and Q2>1(GeV)^2
- comparing to PVDIS rate table in proposal at page 40 of [3]
- Energy Flux drops quickly with R, the peak value at lowest R
EM energy flux on EC (outdated)
- geant3 has EM process total energy cut at 1MeV
- Both SIDIS and PVDIS have confirmed energy flux on EC by the genat3 simulation in the proposals.
- geant4 geometry and materiel checked, no simple mistake found.
- with energy cut on 1MeV, SIDIS geant4 result is close SIDIS geant3, but PVDIS geant4 is still one order larger than PVDIS geant3.
- More careful study like particle type, hit processing under way.
rate on GEM
- rate on GEM need more study, particular from photon-induced rate, SBS has more mature simulation tested with data, their photon-induced rate is about twice of electron rate, need to learn from them.
