Minutes of the 51st Machine-Time Committee Meeting
Date and time: January 20, 2012; 13:30–15:50
Place: RIBF Bldg., Room 203a

Attendees: Sakai (Chair), Aoi
ac, †, ‡, En’yoba, †, Habaaa, †aaaaaa

Sakurai , Shimoura , Ueno , Uesaka , Uwamino , Wakasugi , Yamaguchi
aaa

Absent: Abe , Fukunishi , Morita , Motobayashia, †, Sudaab, Kamigaito , Kase , Kubo , Kubono , Nishimurac, †, Yoshidaba, †,b, †a, †c†‡

RNC / CNS / RIBF-UEC / Observer / TV Attendee(in random order)

Reports
1.

Change of the beam time schedule (Ueno)DD11-02 (Giuseppe) has been canceled in response to the request from the spokesperson.

NP0906-LINAC01-03 (Asai), which was tentatively scheduled for February 1–10 depending on thestatus of beam development, has been canceled due to the much lower current of a 50Ti beam
extracted from the ion source in a test than previously requested. The RILAC beam time (BT) fromJanuary to March has been rescheduled due to the cancelation.

Details of the changes are as follows:
Experimental-Program-Number

previouschangedAVF stand-alone
DD11-02 (Giuseppe)

Feb/13/09:00 – Feb/13/15:00→Feb/01/09:00 – Feb/10/ 9:00
Feb/01/09:00 – Jan/29/ 9:00
Feb/27/21:00 –cancelled→→

cancelled

RILAC stand-alone
NP0906-LINAC01-03 (Asai)
NP0702-LINAC12-15 (Morita)
NP0702-LINAC12-14 (Morita)
ML1006-LINAC27-02 (Haba)

2.

cancelled
Jan/15/09:00 – Feb/10/ 9:00
Mar/12/09:00 –Mar/ 2/09:00 – Mar/ 8/ 9:00

RIBF operation (Kamigaito)
In the 124Xe beam series performed in December, 2011, 85 % of the requested BT was supplied by
the beam delivered at Iave ~ 8.5 pnA on average. In this series, fixed-type foils were utilized as thefirst- and second-stage strippers. It was also reported that the endurance time of the second stripper
foil was so short that it was changed a few times every day.

As reported in the previous meetings, a layer short has occurred in the RRC coil. Preparations for its
repair work, i.e., changing the RRC coil, are underway. The Accelerator Group plans to do the repair
work during this summer. However, if the repair is urgently required, it should be done frommid-May.

3.

Call for BT scheduling requests for the first half of FY2012 (Ueno)
The call for BT scheduling requests for the first half of FY2012 has started since January 11(deadline is January 24). Taking into account the plans of MS (facility’s BT in the Machine Studycategory), constructions, and repair works discussed after the previous meeting, it was announcedthat only 48Ca and 124Xe primary beams will be scheduled for the SRC-use experiments for the firsthalf of FY2012. The BT scheduling timeline is as follows:–

Jan. 11–Feb. 24:

Call for BT scheduling requests & detector development BT requests–Mid-Feb.:

Tentative BT schedule–Feb. 16:

Approval of BT schedule by the MT Committee–Mid–End of Feb.:

Submission deadline of Accelerator Use Planning Sheet (AUPS)–

Mar. 13:

In-House Safety Review Committee meeting–

Mar. 14–End:

Modification of the accelerator-use plan and re-submission of AUPS by
the spokespersons in line with the suggestion from the Safety ReviewCommittee

If it becomes apparent that beams would not be delivered at all at the requested current due to theabove noted layer short of the RRC coil, the repair work of the RRC coil must be done frommid-May by suspending the RIBF operation. The repair work will take three weeks. This decision
will be made based on the beam conditions for the NP0912-RIBF34-02 (Sekiguchi) experimentscheduled for February 21–27 (the beam acceleration starts February 14). If urgent repair is required,the BT schedule for the first half of FY2012 will need to be re-planned starting from the end ofFebruary.

4.

Status of the PAC meetings (Ueno)
NP-PAC–

10th NP-PAC: All procedures have been completed with a summary report prepared by thesecretariat office sent to the directors of RNC and CNS on January 18.

–11th NP-PAC: The dates of the 11th meeting were set to June 18–19, 2012. Following the PAC
meeting, International RIBF Users’ Meeting will be held on June 20–21.



9th ML-PAC & 3rd In-PAC: under preparation

Topics discussed
1. Approval of the minutes of the previous meeting (Sakai)
2. Calculation of BTs of BigRIPS-related experiments conducted in October–December (Sakai)
Actual BTs of the BigRIPS-related experiments in the 238U and 124Xe beam series from October toDecember were reported (Ueno). After discussions, the BTs spent were calculated as follows:–

NP0702-RIBF30-04 (Yoneda): 10 days–

NP0702-RIBF31-04 (Aoi): 3 days–

NP1012-RIBF63-01 (Sumikama): 0 days (BT was canceled)–

NP0702-RIBF09-01 (Lewitowicz): 1 day–

NP0702-RIBF11-06 (Nishimura): 0 days

3. MS proposals still under discussion (Sakai)
Two BT requests in the MS category carried forward from the 47th meeting were reviewed again. Thedecision was made as follows:“SAMURAI Commissioning”, MS11-10 (Yoneda), 6.5 days requested
The decision was “deferred”. The MS proposal should be re-submitted. The decision was entrusted
to the MT Committee chair.

“SHARAQ Commissioning”, MS11-11 (Michimasa), 2 days requested
With the spokesperson turning down 1 day still being deliberated, a BT of 1 day was approved.

4. Handling of the BT for BigRIPS tuning in NP-PAC discussions and BT operations (Ueno)
A tuning time for users’ own equipment and/or detectors using a beam (≡ TU-Tu.) should be indicatedin the column “Tuning with beam” in the NP-PAC application form. It was pointed out at the 47thmeeting, however, that in some cases “tuning time with BigRIPS for RI beam production (≡TBigRIPS)” was cited in this column, and approved as requested. In response to this suggestion, theform will be modified to make this point clear beginning from the 11th NP-PAC meeting. Inaddition, it was also discussed whether the present management of TBigRIPS, given in the following,
should be changed or not. The discussion will ensue.
An extra BT of 0.5 days is commonly added as a TBigRIPS time, because i) it is not easy toevaluate a TBigRIPS part separately from an approved BT if it was partially approved, although inprinciple, the additional TBigRIPS = 0.5 days is not necessary for the BTs approved includingTBigRIPS, and ii) even if TBigRIPS is included, BigRIPS tuning could not be conducted within a BT
if only a short BT was partially approved. When the actual TBigRIPS exceeds 0.5 days, BigRIPS
tuning will be conducted using their own BTs.

The following comments were submitted from RIBF-UEC on this issue (Suda):–If TBigRIPS is commonly fixed to 0.5 days for all the approved experiments, some of theexperiments would be required to have their own BT used. To avoid such a disadvantage tousers, RNC should check all approved experiments for whether TBigRIPS is included or not. Then,appropriate TBigRIPS should be re-allocated on a case-by-case basis so that BigRIPS tuning can be
fully conducted without using a BT for users’ own measurements: TUser = TU-Tu + TU-Data, whereTU-Data is a time for data run.

–Experimental proposals which require changes of BigRIPS setting many times e.g., to use alarge variety of RI beams, should be reviewed by the PAC taking into account a total BT length
including TBigRIPS to check for its feasibility. The TBigRIPS time, however, should not be included
in an approved BT. It should be provided as an extra BT from the facility. In order to allow
applicants to estimate an appropriate TBigRIPS, a guideline should be defined and set clearly.

Taking this opinion into consideration as much as possible, the following management of TBigRIPS
starting from the 11th NP-PAC and the BT scheduling of FY2012 second half has been approved:
In the proposal review process (NP-PAC)
1.

Applicants indicate only TUser (=TU-Tu + TU-Data) in their proposals.

2.

A time of TBigRIPS is evaluated by the in-house technical review based on the submitted proposal.

3.

The PAC reviews proposals in terms of the total time length TBigRIPS + TU-Tu + TU-Data. Thus, theproposal can be approved by this total time length at the maximum.
When a BT is conducted

4.

Although the BT number of TBigRIPS + TU-Tu + TU-Data can be approved at the maximum, TBigRIPS ismanaged not by the users but by the BigRIPS Team. Experimenters can not convert TBigRIPS into
TUser (TU-Tu and TU-Data can be re-arranged by experimenters).
–If various BigRIPS tuning are planned in one BT, the tuning will be carried out all together
by the block or step-by-step. Experimenters can determine the tuning plan by consultatingwith the BigRIPS Team.

–If the actual TBigRIPS takes longer than the scheduled TBigRIPS time, the BT schedule will beextended so as to conserve TUser. If such extension is difficult due to a tight BT schedule, aTUser time spent in the BT will be cut short.

5.

TBigRIPS + TU-Tu + TU-Data is interpreted as the BT provided to users.

6.

For the experiments which have already been approved, the uniform extra BT of 0.5 days isadded as TBigRIPS according to the current policy. If TBigRIPS longer than 0.5 days is needed,
experimenters should use BT from TUser. If users consider that TBigRIPS = 0.5 days is not enough,additional TBigRIPS time can be requested when a call-for-BT-scheduling-requests begins. Then,the allocation of the additional TBigRIPS will be decided by the in-house technical review.

5. Disclosure of the subject titles of NP-PAC proposals (Ueno)
The presentations by representatives are open to public in the NP-PAC meetings. Their research
titles are, however, will be disclosed only if they have been approved. In addition, it is possible notto disclose the title if requested not to. The review of this disclosure policy was discussed at the 49thmeeting. This issue has been carried over from the previous meeting.

After discussions, it was approved to disclose the research titles when proposals are submitted. The
disclosure of research titles will be explicitly notified in the call-for-proposals from the next
NP-PAC meeting. Research titles will be disclosed on the web and other documents before theNP-PAC meeting. RIBF-UEC also agrees to this policy.

6. FY2012 BT operation basic policy (Sakai)With the launch of the EURICA (Euroball RIKEN Cluster Array) project in April, 2012,
international use of RIBF will increase in FY2012. The BT shifts due to possible troubles ofaccelerators and experimental key devices may lead to confusion in making travel arrangements toJapan. Taking this situation into account, the following basic BT operation policy was shown. BTs
will be scheduled without allowing for spare days as much as possible.
In case of a trouble, the relevant BT will not be extended but rather canceled or reduced in order toavoid shifting the entire schedule.

The beam elements for the BT schedule of the FY2012 second half year were suggested. (Sakurai)

7. Next meetings
The next MT Committee meeting will be held on Thursday, February 16, 2012, at 13:30.

The next meeting after the next will be held on Friday, March 16, 2012, at 13:30

Regularly, the meetings in the next fiscal year, starting from April, will be held on the third Friday, at13:30.