Minutes of 119th FFIR/BDSIM and 41st ILC-Asia WG4 meeting on 9/28/2005

ILC Asia WG4 : Minutes of 41st meeting
http://lcdev.kek.jp/ILC-AsiaWG/WG4notes/
September 28 10:00
Rm.425 bldg.3 at KEK.

(1) ATF2 proposal vol.2 status, by T.Tauchi

Although there have been several e-mail exchanges in last week, the drafts of SLAC and UK contributions are still missing. Also, we are waiting for the draft of timeline from Yokoya-san. Minimum of the drafts is written word of the presentations at BDIR2005 workshop.

Since the Vol.1 publication, there are updates in optics/layout of the diagnostics section and various tolerances required for the magnet properties together with specifications of the power supplies. These updates should be included in the Vol.2 .

It was pointed out that collaboration meeting of the ATF2 must be necessary to realize the international project before the GDE meeting in December, Frascati. Even the TV meeting is important.

(2) Shintake monitor, by T.Suehara

( transparency, pdf, 6pages, 5.4MB )
Cleaning up the circuit board, the actuators backed in. Until then, they had memory errors at beginning of operation. Since the new laser is a CW (continuous wave mode) for checking the optics, preamplifiers, which have measured the pulsed laser intensity, must be replaced. The laser system will be transported to the company for the overhaul, while the cost estimation of the shipment seems to be expensive.

We discussed on the beam test of the gamma detector, whose plan was briefly reported. First simulation studies must be done to design the detector with optimization of the performance. The beam test will be the experimental verification of the design. Needless to say, a coordination is taken by a staff member to use a beam line at other institute (AIST etc.) . Since there might be a lot of studies, Suehara is asked to make a task list with priorities and its schedule with assigning responsible persons in each task, especially in this fiscal year. The list would be preliminary.

(3) Optics and magnet group, by S.Kuroda

The 4 skew quadrupole magnets, which exist at present ATF extraction line, will be rearranged in the ATF2 diagnostic section. A question is raised in the discussion; i.e. is there enough space for the rearrangement ? Therefore, S.Kuroda will study the physical configuration and availability of space with help of N.Terunuma and T. Okugi. He will report the summary of this study. Also, the optics group has been asked to estimate the ripple tolerances for all the magnets, which are absolutely necessary to design the power supplies.

(4) Commissioning strategy focused on the necessary instrumentation (discussion)

In the Vol.1, the strategy of commissioning the ATF2 was described. However, necessary instrumentation was not explicitly mentioned. In order to prepare the initial operation of beam, i.e. commissioning, the realistic discussion must be initiated as soon as possible. T.Okugi accepted a contact person in this discussion group from KEK. He will contact to F.Zimmermann at CERN, and he will report the result/plan at next meeting.

(5) Discussion on the BDS-BCD

In last week, Andrei improved the DID field to decrease the field strength near the IP. He asked to estimate the effect, where he expect some reduction of background; i.e. back-scattered gammas in TPC. The detector group will work on this issue. Also, synchrotron radiation background inside the crab cavity from upstream was discussed in order to determine the aperture as well as the resonant frequency.