Minutes of ATF2 weekly meeting, 27 April, 2011

First, we resume the weekly meetings each for one hour in order to prepare next run, this fall 2011, for achievement of goal 1. We will have one or two presentations at each meeting.

We like to remind the new wiki page for ATF/ATF2 which has been announced for improvement of mutual collaboration, e.g. news, beam tuning and visiting plan, operation manuals, common data base of beam line monitors and devices etc. . The new wiki page (http://atf.kek.jp/twiki/bin/view) can be reached here, where the collaboration-page requests your login or registration.

Recovery Plan of ATF after the earthquake on March 11, 2011, N.Terunuma

At present, we do not know that the ATF operation can be extended after April 2013 even with the great earthquake incidence.

Present constraints are (1) radiation safety issues,i.e. monitors to be fully inspected and concrete shields to be fixed as approved, (2) electricity, no limitation for checkout devices and full operation needs approval by KEK and (3) cooling water facility to be inspected and resumed by the KEK facility division in May, where the ATF has second priority while the PF has the first one.

Present status is described as follows. The ATF building ( assembly hall) has no access limitation as the same as before. Total AC power of KEK is 2MW since the earthquake, and it will be 18MW in May. The ATF operation need about 2 MW. The fall down power cables were recovered. The cranes can be used. All the vacuum systems are in operation, while the DR bellows were inspected and fixed. The timing system was checked out so that the RF system is carefully checking out without high power operation. The beamline level was surveyed except for the FF without control of movers. Results are good, especially the inclination of the LINAC decreased from -4mm to -3mm. We will improve the level for the re-alignment target . Rolling was also surveyed to be lager than the tolerance, which will be re-aligned.

The recovery plan is presented for April to July, 2011. The concrete shields will be adjusted/fixed in May, while the shields of LUCX are fixed in this week. In parallel, the cooling water system will be recovered. Then, the RF gun, LINAC and DR/EXT will be checked out in June.

Many pictures were shown for damages and recoveries. Some of them are described at the ATF news of the new wiki page ( http://atf.kek.jp/twiki/bin/view/Main/News ).

Q : After the AC power of 18MW is available, can we operate the ATF in day or night ?

A : We like to operate in day for check out works with the company persons.

C : Contracted total AV power is 24MW with the KEKB shutdown. The 18MW is a saved one by 25% which has been asked by the company/government, especially in day-time. In night, KEK can use the 24MW.

Q : There are only 2 weeks in June for the beamline checkout. How do you manage it?

A : Many instruments can be checked without beam. For an example, the cavity BPM system can be checked by CAL-tone. So, we asked you for such checkout in remote operation, which should be done before the beam operation. KEK will checked out all the hardwares in parallel.

C : You can come to KEK in June,when all the infrastructures will be back on. Even now, the dormitory is available. If you can not, you can remotely participate in beam tuning.

C : Glen moved the FS computer to the SLAC house. It is needed for the stripline check out. We must ask Glen for what are needed in addition to it. He is in vacation.

C : We need such information for other instrument such as OTR system.

Q : Can you/we travel to Japan/KEK?

A : France does not officially allow, while it is personally OK.

A : In UK, it is OK in principle.

A : In US, we have to ask.

Q : Can we operate the ATF in summer, i.e. July ?

A : Since the AC power is shortage, the company will ask us for more saving. So, all accelerators will be off in this summer. While we have no operation of ATF, low level power is available for checkout the instruments and softwares etc. .

Q : What is the situation in fall ? Is it quite same?

A : We do not know how the AC power will be recovered/stabilized. We will do our best to prepare full operation in Autumn.

Q : What is the actual cable movement at IR region ?

A : The cables from the ceiling shield can be disconnect at BPM or electrics hut. The cables route will be changed with consulting to radiation people. They will not come from the ceiling but the side wall. We will disconnect them in tomorrow with the Shintake group.

C : Honda knows cables of BPMs in details. So, please ask him if needed.

Discussion on meeting plan in future

C Stewart : We would like to hear a short status of present work at ATF, hardware and software status, at every meeting.

C Jacqueline: It is important to document current status of the BPM system for analysis of the IPBSM, e.g. background study with IPBPMs, orbits at IP. Are such internal reports available on them ? ( Kamiya-san suggested to ask you (Philip and Andrei) for such arrangement. )

C Philip : At home, we can prepare documentations and execute simulation studies. Such report is important to share the information among the group, e.g. IPBPMs, BPMs to be provided by Stewart and Glen. Do you have any suggestion of recent reports?

Q Jacqueline : How is reliable of the IPBPM data in Dec. 2010 ?

A Stewart : The IPBPMs and two c-band BPMs nearby were just commissioned in December, 2010 and were checked in February, 2011. So, they are still commissioning stage. Results ( calibration and position resolutions) were presented at the ATF project meeting and ALCPG11 . The results were depend on the beam condition and alignment of the 4 BPMs at IR.

Q Oroku : Are the calibration constants available?

A Stewart : The BPM data are calibrated and saved in the data base (EPICS). So, they are included.

Q Jacqueline: We are interested in beam jitter during the IP beam size measurement by Shintake monitor. So, the resolutions should be well-known.

C Stewart : Let's have a separate meeting for more details.

C Philip : Background is not only related to jitters, but it has large fluctuations which should be visible in other parameters.

Next meeting is 11th May, 2011 after the Golden week in Japan.