85th ATF2 weekly meeting

1. Decision of software task leaders ( discussion), Shigeru KURODA (KEK)

We discussed the task leaders with the draft list which has been prepared by S. Kuroda. In the list, the hardware direct tasks were separately listed from the beam tuning direct ones as decided at previous meeting. During discussion, it became clear that hardware direct tasks related to various feedback systems have no specific tasks while they are rather integrated hardware, so no leaders are needed for them.

We decided the leaders, i.e. one leader in each task, as the above excel file.

Also, we decided to have presentations of status, plan and schedule for each task by the leaders at next commissioning meeting, i.e. 30th July. Also, in next weekly meeting (23 July), we will have presentations of the hardware tasks on BPMs, movers and HA power supplies. We would like to know who and when are available at ATF, KEK in August through October, 2008.

KEK site meeting

2. Progress of Shintake monitor (ATF2 IP-BSM) work

Participants : Tauchi, Terunuma, Kuroda, Okugi, Araki, Oroku, Yamanaka and Kamiya(WebEx)

Laser system by T.Yamanaka

Q: Is temperture of cooling water really stable?

1. insert shims between the vertical optical table and the horizontal table
2. move the pulsed laser and the optical table to outside of the concrete shield
3. replace rubber-adaptors by SUS ones between the laser optical table top and its mount .

Q: Do you prepare shims to be inserted?

A: No, we need to procure or make them by then.

Q: Do you really need the replacement of adaptors?

A: Although the vibration of the laser table doesn't affect the measurement so much, we want to prepare the optimum condition.

1. Flash Lamp
   • Lamp will be fired at 1 ms after the trigger input
   • acceptable timing jitter is less than several us
2. Q-Switch
   • Optical Laser output becomes the maximum at 50 ns after the trigger input
   • less than 1 ns timing jitter is needed

• Pre-trigger used by Ext Laser Wire group can be used for Flash Lamp trigger.
• Ext Kicker pulse signal can be used for Q-Switch trigger

Detector of IP-BSM by M. Oroku

1. Simulation study of the analysis methods:
   ON/OFF method and Shot by shot method are considered for the Detector. It is important to perform simulation study changing S/N ratio. Then the proper analysis for the S/N ratio of IP-BSM can be chosen.
2. Calibrations:
   Test the gain curve of photomultipliers
   Test the efficiency of light guides and scintillator
   Additional tests of position dependence of shower in the scintillator in more detail
3. Monitoring system:
   It must be important to monitor gains of all 16 counters in the detector, although present detector has no such system. Accuracy and necessity of monitoring absolute values in addition to relative ones should depend on the detector performance and the analysis method. We would like to know them in details, expecting presentation at next meeting.
4. timing system :
   How to make the trigger of IP-BSM
   candidates:
   a: use the timing system of Laser wire group
   b: construct the original system for IP-BSM