Minutes of the Partner User Council Meeting
Held at Argonne National Laboratory
October 26, 2007


Partner User Council Members/Alternates in attendance: W. Anderson, C. Benmore, B. Bunker, K. Brister, M. Capel, P. Fenter, R. Fischetti, R. Gordon, T. Graber, T. Irving, A. Joachimiak, D. Keane, L. Keefe, K. Moffat, S. Sinogeikin, J. Viccaro, and S. Wasserman.

APS Attendees: K. Attenkofer, M. Beno, J. Cross, S. Davey, R. Gerig, J. M. Gibson, E. Gluskin, D. Mills, G. Srajer, S. Strasser, M. Vigliocco-Hagen and R. Winans.

Routine Business: The minutes of the 08/22/07 Joint APSUO Steering Committee and the Partner User Council Meeting were reviewed and approved as written.

APS Update -- J. Murray Gibson:

Gibson informed the group that a consultant to the laboratory has inspected all sector space in the 400 area for potential OSHA deficiencies. Almost 1,000 were identified, but fortunately, most are not of great significance. An ad-hoc committee on the use of extension cords and power strips has been formed. There were over 200 deficiencies identified on this topic. Gibson advised the group to be proactive in this area.

Also discussed was the budget and the fact that Congress is expected to operate under a Continuing Resolution until March. The initial allocation for FY2008 equaled the FY 2007 budget, but the Continuing Resolution allocated only 86% of the operating budget on a monthly basis. Also, there were unexpected overruns from last year. Advocacy is important now, and users should continue to be proactive.

Gibson also told the group about the UChicago Argonne LLC Review of the APS, which was completed in September. The portions of the report received thus far have been very favorable and have included constructive comments. When all reports are ready, the APS will provide a response and share it with the APSUO Steering Committee and Partner User Council. The initial report on the ASD/AES review is quite favorable. The committee was impressed with the plans for an ERL upgrade, but they also realized that significant R&D is needed to accomplish that goal. The committee felt that the APS had yet to develop a clear plan for that R&D. Such a plan is currently being put together in the form of a proposal to the DOE for support for the required R&D. The committee concluded that the APS is a world-class facility with excellent personnel and facility safety performance. APS appears to have an ongoing safety assessment process consistent with laboratory expectations and has developed and implemented best-in-class experiment review and work approval processes. The committee identified issues in the safety area that included floor coordinator staffing, remote training, establishing clear directions and expectations for APS and CAT personnel regarding safety and compliance, and responsiveness to observations and suggestions made by staff and users. Although the written report on the science portion of the review is not yet available, the committee complemented the APS, pointing out that the overall quality of science was of the highest standards, that the reorganization that took place in April of 2006 seems to have been a positive move, and the CAT-XOR transitions are being viewed as a success. The committee suggested that improvements might be made in the area of workloads and career paths for beamline scientists, a more coherent protein crystallography program, more investment in detectors, more post docs, and more input to APS management from a life scientist experienced in synchrotron radiation. Gibson said that the final report will be sent out and comments requested.

Gibson also announced that the upcoming DOE Review of the APS is scheduled for December 10-13, 2007. The program will involve external and internal speakers, posters and meetings with APSUO and PUC representatives, SAC members, etc. The details of the review have not been finalized, but written input is being solicited at the present time. Gibson thanked all for the help in providing input.

Update on Prototype ERL for R&D Proposal -- E. Gluskin:

Gluskin outlined the APS Upgrade R&D goal, which is to develop and test designs of a novel accelerator system that will deliver several orders of magnitude in brightness and

coherent flux of x-rays. The main R&D topics in the upgrade are beam dynamics of ultra-low emittance e-beam, next generation of SRF systems, and ultra-bright electron source.

  • The ultra-low emittance requires production and preservation with the required bunch charge -- design gun and merger using evolutionary algorithms, targeting 0.1 micron emittance, 2`3 ps rms bunch length for 20 pC/bunch. Such performance has not yet been demonstrated, even in simulation. We must explore options for DC and r guns, both normal and superconducting.
  • Cost-effective configuration that preserves emittance -- develop options for single- and multi-pass linacs in various configurations. Also, explore alternatives to complex TBS-based designs that sufficiently control both coherent and quantum radiation effects.
  • Control of beam instabilities at 25~100 mA average current -- apply standard codes to evaluate and improve lattices and cavities for resistance to beam break-up (BBU) instability. Model ion trapping and explore use of kickers to create bunch gaps. We will develop integrated ELEGANT simulation that includes BBU, resistive wall, chamber wakes, detailed transport, etc.
  • Beam loss level and its reduction and control -- beam halo generation and propagation, starting at the gun. Modeling of beam loss and propagation of shower products. Design of collimation and shielding.
  • Integrated, start-to-end simulations are performed with errors and other practical issues included -- multiple, long, independently-controlled insertion devises combined with a very small beam emittance. Lattice correction techniques that succeed at a level comparable to 3 rd generation light sources. Develop path length adjustment methods to maintain efficient energy recovery in the face of seasonal, tidal, and user-related changes.

Gluskin went on to discuss improving cavity quality Factor Q 0 -- ERL requires continuous wave (CW) rf power. ERL requires continuous wave (CW) rf power. Current state-of-the-art SRF: Q 0 = 1x10 10 for multi-cell cavities; accelerating field gradient of ~ 18 MV/m at 2.0K. ERL wall-plug power with a Q 0 ~ 1x10 10, is on the order of tens of Mw. R&D goal is to improve cavity quality factor by a factor of five, Q 0 ~ 5x10 10

  • Improving surface residual resistance (our goal is to obtain 1n W).
  • Exploring niobium cavity surface coating using atomic layer deposition (ALD)

Investigating other materials (e.g., Nb 3 Sn)

Beamtime set-asides for specific techniques -- G. Srajer:

Srajer explained to the group the reasoning behind the “set-aside” allocations for General User Proposals on XOR Beamlines. This rationale would ensure access to beam time for supported instruments, would support development of new user communities, and would ensure appropriate support for general users with current staff. In this process, the beamline scientist/manager recommends a percentage for set-asides, if needed. The XOR Section Head/XSD Division Director, and the Deputy ALD review and approve these percentages. The BAC then allocates time to General User Proposals by score within the set-asides. A review of other facilities revealed a mix of allocations by score or set-asides. CATs at the APS (GSECARS, ChemMatCARS, and HP-CAT) use a similar set-aside process. In these cases, the CAT Management or Beamline scientists determine the techniques and percentage of time for each prior to the BAC Meeting. The BAC is then notified of techniques and percentages for a particular run before the allocations are made. Currently, directed allocations are necessary for multipurpose beamlines. In the near future, the APS will be asking for input from the user community (APSUO, PUC) and feedback from the Scientific Advisory Committee. The goal is for more dedicated beamlines, which will eliminate the need for directed allocations. The ultimate goal is to schedule beamtime by scores only. Srajer asked for feedback from the user community on this subject and assured those present that the selection of dedicated beamlines will not happen in a vacuum.

2008 Retreat:

The 2008 retreat was discussed. Possible dates were discussed with the group as well as with the APSUO Steering Committee yesterday. As soon as the date is confirmed, notifications will be sent out. A lengthy session on the ERL Upgrade will be included; suggestions are welcome for other discussion topics.

Advisory Groups:

The committee formed to develop guidelines for User Advisory Committees for APS-operated beamlines presented recommendations and guidelines for the formation of these committees. The Council accepted the recommendations as amended during the meeting. The Chair of each Advisory Group will be a member of the Partner User Council. The PUC Charter will be amended to reflect this recommendation.

DOE Review:

Council members requested that there be industrial representation for the review along with Life Sciences specialists. Input on formulation of the agenda was also requested. The issue of the proprietary rates is a concern. Proposals for detectors and optics should also be discussed with the review committee. DOE should utilize the expertise of the user community. Another “critical” issue is the ERL's effect on the current facility. Many of these concerns shown here could also be topics of discussion at the retreat. D. Keane will summarize this list of concerns and send to PUC Members for additional comments.

Life Science/Biology Discussion:

The group discussed the possibility of having a high-level biologist on the staff. It was suggested that the Biology CATs get together to discuss this situation so that these issues are brought to light in the future.

Next Meeting:

The next Partner User Council Meeting will be held on Friday, January 18, 2008.