Recent results

Marc & Qian

Outline

• 3D uniformity scan

• End cap TOF counter test result

• Report of moving laser box

3D Uniformity Scan

• We used USTC DAQ system to do the 13x13 3D uniformity scan = 171 total files, which covers a 3mm x 3mm square area. The reason for 171 is because we repeated the origin measurement three times (1st time is at initial origin, 2nd time is on the grid, 3rd time is final file.)

13

12

11

10

9

8

7

6

5

4

3

2

1

14

26

39

27

40

52

65

53

66

78/79

164

163

150

149

136

135

122

121

108

107

94

93

80

170

157

156

143

142

129

128

115

114

101

100

87

86

X

Y

(0.180,0.215)

Origin (0.240,0.275)

(0.300,0.335)

The percent variation over 2.5mm x 2.5mm ～ 13%.

Summary / Conclusion:

1. We did this test before we move the “Moon” Box.2. We know from our 2 D linear X,Y scans via O-Scope, that we are able to

achieve uniformity on the order of ~4%.3. We now conclude that the USTC/main DAQ interface requires more fine

tuning.4. We know from the ref-PMT data (reading from faster O-Scope) that the

laser is quite stable.5. (To be continued…)

End cap TOF counter test

Hole A

Hole B

We set the HV of EC and Barrel TOF separately to achieve both gain = 1E+5.

The Barrel TOF signal’s PH is 165.1 mV.

EC TOF Signal PH (mV) Wiggle fiber

Hole A 161.1 160~161 mV

Hole B 260.0 255~260 mV

Hole AHole B

For Hole B, if we use solenoid 3 with 63% transparency, the PH is 164 mV

Summary / Conclusion:

1. According the EC TOF Fiber installation method, the both holes are easy to achieve.

2. Using Hole A, we don’t need to use solenoid 3 or filter, the EC TOF and Barrel TOF signals’ PH are almost the same, and Hole A is more stable than Hole B when we wiggled the fiber.

Marc & Qian老善　刘倩

Moving Laser Box

Before we moved the Moon Box, we tested the Ref-PMT PH:

Origin PMT (mV) PH (mV)

CH1(east) (0.305,0.330) 460 202.0

CH2(west) (0.240,0.275) 486 202.0

We’ve moved the “Moon Box” into the rack.

Then we tested the PH:CH1 (460): 185.8 mVCH2 (486): 195.8 mV

Summary / Conclusion:

1. After we moved the moon box, we need to do the alignment again.2. The PH decreased about 8%.

Marc & Qian老善　 刘倩