Minutes of the 47th Machine-Time Committee Meeting
Date and time: September 22, 2011; 13:30–16:10
Place: RIBF Bldg., Room 203
Attendees: Sakai a (Chair), En’yo a, †, Fukunishi a, Hayashi a (in lieu of Abe), Kase a, Kubo a, Morita a, Sakurai a,Shimoura b, Teranishi c, †, Ueno a, Uesaka a, Uwamino a, Wakasugi aAbsent: Abe a, Haba a, †, Kamigaito a, Kubono b, Motobayashi a, †, Yoshida a, †a

RNC / b CNS / c RIBF-UEC / † Observer(in random order)

Reports1.

Beam-time schedule changes (Sakai)
On September 7, it was announced by the Executive Director in charge of facilities that the plan forenergy conservation measures to be applied to the Wako Institute effective from September toMarch 2012 has been modified. In the revised plan, a maximum of 2.8 MW of the portion of
external electric power supplied by Tokyo Electric Power Company to Nishina Center (RNC) will
be newly provided. In response to this modification, the following AVF/RRC beam times (BTs) wait
listed for the second half of FY2011 has been scheduled for September. It was noted that themaximum electric power available for RNC will be cut by 1 MW starting from October to the end of
this fiscal year.

–

RI0702-AVF04-27 (Haba et al., AVF-C03, Sept.24 at 21:00–Sept.26 at 21:00)–

RI0702-AVF04-28 (Haba et al., AVF-C03, Sept.27at 9:00–Sept.29 at 9:00)–

IB0702-RRC01-43 (Abe et al., AVF-RRC-E5B , Sept/30 aｔ 9:00–Sept.30 at 12:00)–

ML0901-RRC20 -08 Izumi et al., AVF-RRC-E5B, Sept.30 from 12:00–18:00)

With this measure however, there is concern that the shortage of electric-power supply may occur
when a RILAC/AVF single-use experiment runs in parallel with a BigRIPS-based experiment. In
such cases, reduction of power consumption in RNC may be requested. (Kase)

2.

Status of the SHE experiment (Morita)
Results obtained in the SHE experiment during the first half of FY2011 were reported. When comparedwith the results obtained in the previous BTs in which SHE events were observed, there was no
significant statistical differences found for both Z = 112 and 113 measurements.

3.

RIBF operation (Kase)

AVF repair
The damaged O-ring and Dee electrode of the AVF chamber have been replaced by new ones. Abeam acceleration test of AVF at the frequency f= 23 MHz was successful. The test will be also
conducted at f= 14, 16 MHz and other frequencies.

RRC repair
As the location of an RRC layer short has not been identified, RRC must operate in the existingcondition this autumn and winter. In addition, the trim coil system for RRC was damaged but will becompletely repaired next week.
4.

Status of the PAC meetings (Ueno)
NP-PAC–9th NP-PAC: The PAC report was sent to all representatives on July 20 following the approvalof the report by the RNC & CNS directors. With a summary report sent out from the NP-PAC
secretariat to both the directors on August 1, all procedures have been completed. Improvements
is needed in the time unit requested for BT, announcement of the revision of RIB production
yields, the guideline for multiple proposal submissions and/or presentations by the same person,and expanding the scope of the RNC participants invited to an informal gathering to promote theexchange of ideas among the members customarily held on the evening of the first day of thePAC meetings.

–10th NP-PAC: The meeting is scheduled for December 9-10. The call-for-proposals wasdistributed on September 15 (the submission deadline was set on October 20).

ML-PAC: The 8th ML-PAC meeting was held on September 5-6 as scheduled. There were noproposals submitted for the RIBF-related BT.

In-PAC: The 3rd In-PAC meeting will be held after the new head of the Industrial Cooperation Teamis appointed in October.

Topics discussed
1. Approval of the minutes of the previous meeting (Sakai)
2. Review of Machine Study (MS) and Detector Development (DD) (Sakai)
New proposals in the MS and DD categories were reviewed through interviews or presentations by theexperiment spokespersons.
The following MS proposals were approved:
Accelerator development–

MS11-12 (Hasebe et al., 238U, RILAC2-RRC, foil baking, 2 days)*1–

MS11-13 (Kuboki et al., 86Kr, RILAC, gas stripper tests, 3 days)–

MS11-14 (Sakamoto et al., d ↑, AVF, beam study, 1 day)RIBF key experimental devices (whose construction has been approved by PAC / TAC)–

MS11-03 (Kubo et al., 124Xe, BigRIPS, secondary beam production, 6 days)*2–

MS11-09 (Kubo et al., 238U, BigRIPS, secondary beam production, 14 days)*2–

MS11-16&17 (Nishimura & Doonenbal et al., 18O, EURICA commissioning, 2 days×2)
The review of the following two proposals will continue:–MS11-10 (Yoneda et al., 18O, SAMURAI commissioning, 6 days)–

MS11-11 (Michimasa et al., 18O, SHARAQ commissioning, 2 days)

The following DD requests were approved:–DD11-01 (Ishiyama et al., 40Ca, AVF, 1 day)*2–

DD11-02 (Lorusso et al., 40Ca, AVF, 6 hours)*1This request was approved without any presentation or interview since the baking of a stripper foil
is required to deliver a 238U beam.
*2
The proposals have already been approved in the past MT Committee meetings.

3. FY2011 second half-year BT schedule (Sakai)A plan for the BT schedule was proposed by working group. After discussions, the plan wasapproved except for the aforementioned two MSs (the BT allocation are tentative for them).

The members of the working group are: Fukunishi, Haba, Kase, Kubo, Kubono, and Ueno from theMT Committee and Nakagawa TL, Okuno Deputy Group Director, and Sakamoto TL from theAccelerator Group, and Inabe from the BigRIPS Team as an observer. The plan was discussed at theWG meeting held on August 11. The plan was disclosed to the spokespersons who submitted aBT-scheduling request. Comments and further requests from them in response were received during
the next two weeks. The plan was then revised so as to reflect such requests to the full extent
possible. The In-House Safety Review Committee meeting was held on September 14 based on thisBT plan. (Ueno)

4. BT cancellation in response to the 9th NP-PAC report (Ueno)
In response to the PAC report, a backlog of NP0702-RIBF28 (Takeuchi), BT = 2.3 days, was canceled,and upgraded to NP1106-RIBF73 (Steppenbeck & Takeuchi).
5. Definition of “tuning with beam” of BigRIPS-based experiments in the NP-PAC proposal form(Ueno)
It was pointed out by Kubo that from his experience in conducting the technical review of NP-PAC
proposals, the interpretation of “tuning with beam” given in the proposal submission form varies amongpeople (i.e., "tuning of RI beam production" and "tuning of experimental setups with beams" are mixed).
In order to clarify the definition, it is also necessary to discuss whether i) BT should be approved toinclude the secondary-beam tuning or ii) BT for only datarun should be approved, with time for thesecondary-beam tuning externally provided after an appropriate time length is estimated by the facilityside. In the case of ii), a guideline for an appropriate time length of secondary-beam tuning is needed
when frequent secondary-beam tuning is requested. The discussion will be continued through theexchange of opinion with the RIBF-UEC.
6. Next meetings
The next MT Committee meeting will be held on Friday, October 21, 2011, at 13:30.

The meeting after the next will be held on Friday, November 18, 2011, at 13:30.

The next meeting after the next will be held on Friday, December 16, 2011, at 13:30.