1

Recap Clamp for MuTr Station-3

Itaru NakagawaFor the PHENIX Muon Trigger

Upgrade CollaborationEspecially credit to:Tsutomu Mibe (KEK)Yoshinori Fukao (RIKEN)Yoshimitsu Imazu (RIKEN)Kentaro Watanabe (Rikkyo)

2

MuTr Cross Talk

HV (1800 V)

1 MWAnode wire

1 MW

100 pF ....

Cathode strips (96 strip)

~0.1 pF/strip

Rise time of anode signal ~ 10 nsec

Removed to reduce HV trips

Anode Readout

100mV

3V

Serious Issue for Big Pulse

Pointed out by Tsutomu Mibe@KEK

Decap

Doesn’t exist.

3

SolutionHV (1800 V)

1 MWAnode wire

100 pF ....

Cathode strips (96 strip)

~0.1 pF/strip

Rise time of anode signal ~ 10 nsec

R<<1M W1 MW

Additional Circuit to let anode current escape to ground.

4

Pads for surface mount capacitorsLeft over Solder + Coating

To Anode Wire

MuTr Station-3 Anode Card

Capacitor (Removed)

5

North Station-3 Anode Gap

25mm28mm

Geometrical Constraint

Anode cards are only accessible from their back. Front pattern can only be visible using an inspection mirror.

6

Mounting A Clamp on Anode Card

Probe

Gap-1 Station-3 Anode Card

Screw

Station-3 Chamber

Capacitor

Pad

Gap-2 Station-3 Anode Card

28mm

MuID SideIP side

Anode card

Clamp

7

Recap Clamp Prototypes

半田の残りかす(C) ShinEtsu Rubber Co.： EC-BM300 (2.5Wcm)

(A) 4 pin probes

(B) single pin probe

8

Advantage/Disadvantage of Different Prototypes

Advantage

Disadvantage

9

Effect of Recap

10

Test Bench Setup

90Sr Source

Anode wire

Strip

#22

w/ and w/o Clamp

11

Comparison w/ .vs w/o Terminator

22

27

17

Trigger

w/o Clamp

Strip#

22

27

17

w/ Clamp w/ Clamp

Trigger

w/o Clamp

Comparison w/ .vs w/o Clamp

w/o Clamp

With Clamp

Strip Number

Aver

age

ADC

[cha

nnel

]Conductive Rubber

12

13

Towards Successful Installation

14Fiber Scope

Alignment

Spacer determines Transversedirection within ~ 300mm.

Possible misalignment can be found by visual inspection using a fiber scope

Fiber scope shot

15

Electrical Contact

Readout socket

Readout BoardElectrical Contact will be confirmedby measuring Voltage using temporaryreadout tool.

To be removed after the measurement.

16

Clamp Coating Max Current Average Current

w/o w/ <1uA <1uA

w/ w/o >100uA Tripped after 2 min.

w/ w/ 1uA 1uA

w/ w/o >100uA Tripped after 1min.

w/ w/ 2uA 2uA

Extreme Breathing TestHV=1900VDuration 2min

17

Installation Proposal

To be installed North Bottom Octants

18

Summary

• We have developed prototype clamps for re-capacitation to MuTr St-3.

• Good Contact was established more than 90% channels with present design in North MuTr.

• We propose to install 3 different prototypes (each 20) to North bottom Octants for Run11.

• They can be uninstalled during Run if they cause trouble in HV operation.

19

Backup Slides

20

ADC

MIP

MIP

Event Display of ADC Distribution　

Strip

Gap 1Stereo

Gap 2Stereo

Gap 3Stereo

Gap 1NonStereo

Gap 2NonStereo

Gap 3NonStereo