Jin Huang
BNL
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GEANT4 customary code
PHENIX simulation/analysis
EICROOT by EIC taskforce at BNL (learning)
J. Huang <jhuang@bnl.gov>
RICH Discussions
2
J. Huang <jhuang@bnl.gov>
RICH Discussions
3
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Basis:
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Event generator:
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Analysis:
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Portability:
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I like this strategy for single detector R&D projects
◦ Based on Geant4 and ROOT for TTree output
◦ Run a separate ROOT macro for analysis
◦ Single particle
◦ Need external G4 simulation for full event simulation
◦ ROOT based analysis
◦ Everywhere that run GEANT and ROOT
◦ Lack of code basis (e.g. digitalization)
◦ Need some work to join future project (out of our scope)
◦ Example to start: G4/example/advanced/Rich (LHCb RICH)
◦ Running this way for SoLID calorimeter tuning
◦ Hubert’s study
J. Huang <jhuang@bnl.gov>
RICH Discussions
4
J. Huang <jhuang@bnl.gov>
RICH Discussions
5
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Basis:
◦ Based on Geant4 and phenix analysis software
◦ Integrate geometry definition and subsystem construction
◦ Run GEANT4/analysis in one or separated root session(s)
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Event generator:
◦ Single particle/pythia/HepMC file
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Analysis:
◦ ROOT based analysis/PHENIX software base
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Portability:
◦ NONE. Can only run on PHENIX central computing environment
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Not recommended for this project
◦ But may borrow some useful bits
J. Huang <jhuang@bnl.gov>
RICH Discussions
6
arXiv:1402.1209
Aerogel
EM Calo.
Gas RICH
DIS e-
TPC
Hadron Calo.
GEMs
BBC
IP
EMCal
J. Huang (LANL), K. Boyle (RBRC)
DNP 2013
7
Aerogel RICH
1<η<2
DIRC
-1.2<η<+1
eGEM
Detector coverage for hadron PID
Gas RICH
1<η<4
TPC
GEMs
IP
RICH
Mirror
Hadron PID
Coverage
SIDIS x-Q2 coverage with hadron PID in two z-bins
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Aerogel RICH
◦ Collaborate with gas RICH
to cover 1<η<2
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Gas RICH: next slides
J. Huang (LANL), K. Boyle (RBRC)
DNP 2013
8
R (cm)
High momentum hadron ID require gas
Cherenkov
◦
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RICH Gas
Volume (CF4)
CF4 gas used, similar to LHCb RICH
Beautiful optics using spherical mirrors
Photon detection using CsI−coated GEM
in hadron blind mode
Magnetic field line most along track
within the RICH volume
→ minor ring smearing due to track
bending
Active R&D:
recent beam test by the stony brook
group
Courtesy: Stonybook group
Fermilab T-1037 data
Ring size (A.U.)
spherical
mirror
center
IP
Focal plane
HBD detector
Entrance
Window
η=2
η=3
η=4
Z (cm)
PID purity at η=4 (most challenging region w/ δp)
Purity

η=1
J. Huang (LANL), K. Boyle (RBRC)
DNP 2013
9
photon tracking in full event
RICH Ring
J. Huang <jhuang@bnl.gov>
RICH Discussions
10
J. Huang <jhuang@bnl.gov>
RICH Discussions
11

Basis:
◦ Based on FairRoot which drive several simulation model
(GEANT3/4, fluka) through ROOT
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Event generator:
◦ Single particle, Pythia (and many other EIC generators)
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Analysis:
◦ ROOT based analysis/ FairRoot software base (e.g. Kalman
filter)
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Portability:
◦ Get the code:
http://svn.racf.bnl.gov/svn/eic/eicroot/trunk/INSTALL
J. Huang <jhuang@bnl.gov>
RICH Discussions
12
J. Huang <jhuang@bnl.gov>
RICH Discussions
13
J. Huang <jhuang@bnl.gov>
RICH Discussions
14
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Based on BaBar Coil, central field = 1.5T
Field Return
◦ Central and forward hadron calorimeters (iron plate-scint. sampling)
◦ Lampshade Yoke
◦ End cap yoke for e-going direction
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η=+1
Detectors that use/sensitive to field
◦ Tracking: TPC for central η, GEMs for forward directions
◦ Gas RICH detector, field effect is small
R (cm)
HCal
η=-1
DIRC
R (cm)
HCal
EMCal
BaBar Coil
-1.2
EMCal & Preshower
EMCal
RICH
TPC
p/A
GEMs
z ≤ 4.5m
GEMs
Station1
Outgoing
hadron
beam
η= 4
eGEM GEM GEM z (cm)
Station2 Station3 Station4
J. Huang <jhuang@bnl.gov>
ZDC
Roman Pots
z≈12 m
z≫10 m
RICH Discussions
15
A RICH Ring:
Photon distribution due to tracking bending only
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Field calculated numerically with field
return
Field lines mostly parallel to tracks in
the RICH volume with the yoke
We can estimate the effect through
field simulations
r̂
R
R < 52 mrad for C4F10
Dispersion
ΔR <2.5 mrad
ˆ
η~1
EMCal
RICH
η~4
J. Huang <jhuang@bnl.gov>
RICH Discussions
16