Chunha Chen
Hampton University
Hampton Group Meeting on Mar.16,2010
E05-115 setup
y
HES
detector
HES
New
splitter
2.344GeV
e beam
x
D
e’
HKS
Q2
Q1
D
Q1
Q2
K+
Target
z
HKS
detector
Kinematics of the E05-115 Experiment
Electron beam
M.Q.Tran et al.
PLB445 (1998) 20
Momentum: 0.844GeV/c ±17%
Angular acceptance: 3°〜9°

Momentum: 2.344GeV/c
+p +K+
Scattered electron
Target
nucleus
Coincidence
measurement
1.5GeV *
p
K+
Momentum: 1.2GeV/c ±12.5%
Angular acceptance : 1°〜13°
HES-HKS Data Condition
-High multiplicity -
Particles on HKS side: kaon, pion, positron and proton
HKS Drift Chamber Tracking Idea
 Start time of the drift time can not involve momentum
information- Do Timing Counter Pre tracking, project
the time to HDC1&2 by geometry.
 The most possible hit selection is necessary for the
case that there are several hits on the same layer of
HDC1&2 for one space point.
 Both Start time and Stop time should be decided
individually for every single track compare to do
average.
HKS Drift Chamber Tracking Idea
-Geometry-
DC1
DC2
1X
2X
Preliminary Improvement