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| Line 1: |
Line 1: |
| − | = Luminosity and radiation thickness =
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| − | PVDIS
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| − | 50uA,
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| − | LH target, 40cm, 0.071g/cm3, X=40/890.4=4.5e-2, Lumi=50e-6/1.6e-19*40*0.071*6.02e23=0.53e39/cm2/s
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| − | LD target, 40cm, 0.169g/cm3, X=40/745.4=5.4e-2, Lumi=50e-6/1.6e-19*40*0.169*6.02e23=1.27e39/cm2/s
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| − | Al window, 2*100um, density 2.7g/cm3, X=2*100e-4/8.897=2.25e-3, Lumi=50e-6/1.6e-19*2*100e-4*2.7*6.02e23=1e37/cm2/s
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| − |
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| − | SIDIS He3
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| − | 15uA
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| − | 3he(10amg), 40cm, density=10*44.6(amg=mol/m3)*3.016(g/mol)=1.345e-3g/cm3, X=40/(67.42/1.345e-3)=0.8e-3, Lumi=15e-6/1.6e-19*40*1.345e-3*6.02e23=3e36/cm2/s, pol Lumi = 3e36/3 = 1e36cm2/s
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| − | GE180 glass window, 2*120um, density 2.76g/cm3, X=2*120e-4/(19.4/2.76)=3.4e-3, Lumi=15e-6/1.6e-19*2*120e-4*2.76*6.02e23=3.74e36/cm2/s
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| − |
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| − | GE180 Aluminosilicate Glass Composition,
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| − | refer to http://galileo.phys.virginia.edu/research/groups/spinphysics/glass_properties.html
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| − | Molecule Composition by weight
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| − | SiO2 60.3%
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| − | BaO 18.2%
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| − | Al2O3 14.3%
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| − | CaO 6.5%
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| − | SrO 0.25%
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| − | Z/A 0.4829
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| − | radiation thickness 19.4246 g/cm2
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| − | radiation thickness 7.038 cm
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| − | density 2.76 g/cm3
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| − | assume Z=17 and A=35,which gives correct Z/A, then we got nuclei luminosity for each window 3.74/2/35=0.054e36/cm2/s
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| − |
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| − | SIDIS proton
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| − | I = 100nA, Target = NH3, density of NH3(den) = 0.819 g/cm^3
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| − | target thickness (t) = 2.826 cm, packing fraction(PF) = 0.55
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| − | NH3 target is immersed in liquid He4, density of LHe4 = 0.145 g/cm^3 at 1K
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| − | Luminosity of NH3 = den * t * PF * (I/1.602e-19)*6.022e23 = 0.819*2.826*0.55*(100e-9/1.602e-19)*6.022e23 = 4.785e35/cm2/s
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| − | pol Lumi = 4.785e35/17*3 = 0.844e35/cm2/s
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| − | Luminosity of LHe4 = den * t * (1-PF) * (I/1.602e-19)*6.022e^23 = 0.145*2.826*0.45*(100e-9/1.602e-19)*6.022e23 = 0.69e35/cm2/s
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| − | Luminosity of two LHe4 outside = 0.145*2*0.432*(100e-9/1.602e-19)*6.022e23 = 0.47e35/cm2/s
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| − | Total luminosity = (4.785+0.69+0.47) * 1e35 = 5.945e35/cm2/s
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| − | Note: there are several thin Al windows, but their luminosities are small
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| − |
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| − | total length of NH3+LHe4 and two LHe4 outside, 2.826+2*0.432=3.69
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| − | average density of NH3+LHe4, (0.819*0.55+0.145*0.45) = 0.5157
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| − | average density of NH3+LHe4 and two LHe4 outside, (0.5157*2.826+0.145*2*0.432)/(2.826+2*0.432)=0.43
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| − | Composition by weight of NH3+LHe4 and two LHe4 outside
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| − | NH3 0.819*0.55*2.826/(2.826+2*0.432)/0.43=0.80
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| − | LHe4 0.145*0.45*2.826/(2.826+2*0.432)/0.43=0.12
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| − | two LHe4 outside 0.145*2*0.432/(2.826+2*0.432)/0.43=0.08
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| − | average Z=10*0.80+2*0.12+2*0.08=8.4
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| − | average A=17*0.80+4*0.12+4*0.08=14.4
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| − | Z/A=0.583
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| − | assume Z=7 and A=12,which gives correct Z/A, then we got nuclei luminosity 5.945e35/12=0.495e35/cm2/s
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| − |
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| − | JPsi
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| − | 3uA
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| − | LH target, 15cm, 0.071g/cm3, X=15/890.4=1.7e-2, Lumi=3e-6/1.6e-19*15*0.071*6.02e23=1.2e37/cm2/s
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| − | Al window, 2*100um, density 2.7g/cm3, X=2*100e-4/8.897=2.25e-3, Lumi=3e-6/1.6e-19*2*100e-4*2.7*6.02e23=6e35/cm2/s
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| | | | |
| | = rate = | | = rate = |
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.
