Solid Background

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Luminosity and radiation thickness

PVDIS 

50uA, 
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 
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
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

SIDIS He3 

15uA
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
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

GE180 Aluminosilicate Glass Composition, 
  refer to http://galileo.phys.virginia.edu/research/groups/spinphysics/glass_properties.html
  Molecule 	Composition by weight
     SiO2	 	60.3%
     BaO 	 	18.2%
     Al2O3		14.3%
     CaO 	 	6.5%
     SrO 	 	0.25% 
  Z/A 	                   0.4829 
  radiation thickness 	   19.4246 g/cm2
  radiation thickness 	   7.038 cm
  density                 2.76 g/cm3
  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

SIDIS proton 

I = 100nA, Target = NH3, density of NH3(den) = 0.819 g/cm^3
target thickness (t) = 2.826 cm, packing fraction(PF) = 0.55
NH3 target is immersed in liquid He4, density of LHe4 = 0.145 g/cm^3 at 1K
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
pol Lumi = 4.785e35/17*3 = 0.844e35/cm2/s
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
Luminosity of two LHe4 outside   =  0.145*2*0.432*(100e-9/1.602e-19)*6.022e23 = 0.47e35/cm2/s
Total luminosity = (4.785+0.69+0.47) * 1e35 = 5.945e35/cm2/s
Note: there are several thin Al windows, but their luminosities are small

total length of NH3+LHe4 and two LHe4 outside, 2.826+2*0.432=3.69
average density of NH3+LHe4, (0.819*0.55+0.145*0.45) = 0.5157
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
Composition by weight of NH3+LHe4 and two LHe4 outside
   NH3                   0.819*0.55*2.826/(2.826+2*0.432)/0.43=0.80
   LHe4                  0.145*0.45*2.826/(2.826+2*0.432)/0.43=0.12
   two LHe4 outside      0.145*2*0.432/(2.826+2*0.432)/0.43=0.08
average Z=10*0.80+2*0.12+2*0.08=8.4
average A=17*0.80+4*0.12+4*0.08=14.4
Z/A=0.583
assume Z=7 and A=12,which gives correct Z/A, then we got nuclei luminosity 5.945e35/12=0.495e35/cm2/s

JPsi 

3uA
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
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

rate

The result is at /work/halla/solid/evgen

SIDIS e and hadron rate

generated by "collider", the code and script for analyzing result are at https://jlabsvn.jlab.org/svnroot/solid/evgen/collider

The result is here

single particle rate

various particle from vertex is estimated by "eicRate" in our event generator repository. The code and script for analyzing result are at https://jlabsvn.jlab.org/svnroot/solid/evgen/eicRate_20101102 https://jlabsvn.jlab.org/svnroot/solid/evgen/eicRate_20101102/output

rate study

pdf Comparison with 6GeV transversity data by Xin Qian

pptx pdf event generator rate comparison, study by Zhiwen Zhao and Zhihong Ye

pdf study by Nguyen Ton and Xiaochao Zheng (outdated)

background

intro

EM background is estimated from shooting beam into target with SoLID GEMC

background from eDIS, eES and hadron are using the rate from code "eicRate" at vertex as input into SoLID GEMC

low energy neutron crsssection was turned

run 1

It was done by Zhiwen Zhao in later 2013

The code and log files are in SVN at https://jlabsvn.jlab.org/svnroot/solid/solid_gemc/analysistool/background

working dir with output files /work/halla/solid/sim/solid_gemc/solid_simulation_run1

main report for PVDIS_LD2 pptxpdf and SIDIS_He3 pptx pdf 

for different detector and for different particles, we have histograms showing rate
"Eklog_R_hitid_pid" rate(kHz/mm2) at R(cm) and log10(Ek)(GeV) with bin(300, 0, 300, 200,-6,1.3)
"Eklog_R_high_hitid_pid" rate(kHz/mm2) at R(cm) and log10(Ek)(GeV) with bin(300, 0, 300, 200,-6,1.3) for Phi (0,6)deg
"Eklog_R_low_hitid_pid" rate(kHz/mm2) at R(cm) and log10(Ek)(GeV) with bin(300, 0, 300, 200,-6,1.3) for Phi (6,12)deg
"Eklog_R_Phi_hitid_pid" rate(kHz) at Phi(deg), R(cm) and log10(Ek)(GeV) with bin(48,0,12,300, 0, 300, 200,-6,1.3)
"P_R_hitid_pid" rate(kHz/mm2) at R(cm) and P(GeV) with bin(300, 0, 300, 1100,0,11)
there are many other histograms produced with similar names

Because all histograms are produced the same way. One can simply add root files together by "hadd" to look at the result in sum

 hitid =0 - 5  GEM plane 1 - 6
        6       LGCC  PMT
        18      LGCC  front
        7       HGCC  PMT         
        19      HGCC  front
        8 - 11  FAEC front,middle,inner,rear 
        12 -15  LAEC front,middle,inner,rear 
        16,17,26 MRPC front,glass,gas
        20 - 25  GEM plane 1 - 6 front
        27 - 28  SPD front,scintillator
  pid =0   photon+electron+positron
       1   photon    
       2   electron + positron
       3   neutron
       4   proton
       5   pip
       6   pim
       7   Kp
       8   Km
       9   Kl
      10   other

run 2

It was done by Zhiwen Zhao in later 2014

The code and log files are in SVN at https://jlabsvn.jlab.org/svnroot/solid/study/background

working dir with all output /work/halla/solid/sim/solid_gemc/solid_simulation_run2

table for normalization factor comparison pdf pptx

more hit_id are added, some are changed 

 =========    hit_id and pid definition ==============
 hitid  =0 - 5 6 GEM planes, unused
         29 - 40  6 GEM plane, 1st layer (odd) and 2nd layer (even) of gas		
         20 - 25  6 GEM plane front			
         6,18    LGCC  PMT, front
         7,19    HGCC  PMT,  front
         8 - 11  FAEC front,middle,inner,rear 
         12 -15  LAEC front,middle,inner,rear 
         16,17,26 MRPC front,gas,glass
         27-28 FASPD front, inner
         41-42 LASPD front, inner
   pid =0   photon+electron+positron
        1   photon    
        2   electron + positron
        3   neutron
        4   proton
        5   pip
        6   pim
        7   Kp
        8   Km
        9   Kl
       10   other

other staff

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:

Geant4 truegemrate.png

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.

Emflux.png

SIDIS Geant4 modeled background from Target

Sidisgem.png

<math>\pi</math>/e Ratio

See here

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