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SLAC National Accelerator Laboratory

SSRLUO Executive Committee Meeting Minutes

Meeting Notes: Friday, June 6, 2008, 1-4 pm

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Participants (many via conference call):

Uwe Bergmann, Lisa Dunn, Serena DeBeer George, Bob Hettel, Katherine Kantardjieff, Chris Kim, Cathy Knotts, Donghui Lu, Wayne Lukens, Jill Meyers, Art Nelson, Stephane Richard, Riti Sarangi, Steve Sekula, Monika Sommerhalter, Jo Stöhr.

Wayne Lukens, SSRLUOEC Vice Chair, opened the meeting and welcomed the participants.

Regarding the graduate student vacancy on the committee, Justin Jiang from UCSC expressed interest in filling that vacancy. In accordance with the SSRLUOEC charter, the committee agreed to appoint Justin Jiang to fill the vacancy on an interim basis and to include him as a candidate during the next election to be held in October. Nominations are sought for the two other vacancies on the SSRLUOEC next year (materials science and biospectroscopy). Action: Cathy Knotts will notify Justin Jiang. Users are encouraged to nominate candidates to fill the other vacancies for the October election.

Serena DeBeer George discussed some of the changes in how access to the SSRL Sample Preparation Labs is granted and training that is required. Chris Kim shared his perspective on the usefulness of the new training since his group had just completed it. Action: Serena invited users to continue to share feedback related to SSRL labs with the new lab manager, Cynthia Patty.

Monika Sommerhalter discussed the user suggestion for shorter allocations of beam time to more efficiently utilize crystallography beam time. On the last survey a few users noted that long blocks of beam time (such as over weekends) were hard for users to fully utilize. Other users suggested that SSRL consider scheduling group blocks for these periods. Action: Monika will start a discussion on the SSRLUOEC google group forum to solicit additional input from the crystallography user community on the impact of robotics and automation on data collection and beam time needs; scheduling preferences; and interest in being part of larger crystallography teams for more flexibility and better beam time coverage.

There was a brief discussion in response to the request to consider adjusting dates for accelerator physics (AP) to the weekends in order for users to have more access to user support staff and to allow more frequent changeovers and shorter allocations for crystallography stations (not currently available on weekends). There was little support to change the AP once per month from Monday-Tuesday to Saturday-Sunday because the AP shifts frequently involve other groups at SLAC who are only available during weekdays, and BL scientists and support staff use the weekday AP for BL maintenance, commissioning and to set up for user experiments coming on after the AP.

Bob Hettel reported that higher current operation will require top-off injection so top off has been the priority. The top-off plans are a work-in-progress. During the mini-down in July, we plan to install interlock components which are needed for top off. There is a possibility that some beam lines could open during the last few weeks of this run in top off mode (but this has not yet been agreed or confirmed since some minor radiation has been detected at some beam lines during the initial tests, and work is needed to identify and understand how this is occurring). Additional work is planned during the summer shutdown, including transport line to bring beam to beam lines, vacuum lines, etc. Engineering changes (which requires resources) still need to be implemented. SSRL will continue to evaluate what is needed for higher current operation and to determine what higher current is possible without degrading thermal stability and problems with optics (perhaps beginning with 200mA operations). ACTION: Users would like to continue this discussion with more specific information on what changes are planned for the beam line instruments with higher current (e.g, filters?).

In response to the request to extend available beam time to users at the start of accelerator physics when the AP schedule allows (e.g., if/when there is useful beam before AP physics studies begin), Bob Hettel said it could be possible to offer this 'bonus time' to users but it was dependent on AP plans and must be coordinated with their schedule. If users would like to utilize these last few minutes for late measurements, they should contact James Safranek who organizes the AP schedule as well as SPEAR control, Duty Operator and beam line scientific and support staff.

Robert Szilagyi recently created a virtual meeting space through Google to facilitate bidirectional communication with the user community and the SSRL-UOEC. ACTION: Users are encouraged to join the group and use the forum to discuss topics of interest.

Katherine Kantardjieff and Chris Kim will co-chair the Synchrotron and Neutron Users' Group (SNUG). A trip to DC is being discussed for later this year. SNUG website is pending updates:

Steve Sekula, Vice Chair of the SLAC Users' Organization (SLUO), and Jill Meyers (SLUO Administrator) attended the meeting to facilitate interaction between the user communities. They invited SSRLUOEC members to participate in their annual meeting which is being planned for September 18th. Steve provided information on a user advocacy website:

Wayne Lukens summarized plans for the 2008 LCLS/SSRL Users' Meeting (Co-Chairs: Wayne Lukens, Riti Sarangi, Aymeric Robert, Linda Young), which will include sessions to focus on LCLS and SSRL as well as a joint session, see

  • October 15 - LCLS Science & Instrumentation Sessions; SSRL Workshops
  • October 16 - Joint LCLS/SSRL Plenary Talks, Award Presentations
  • October 17 - SSRL Science & Instrumentation Sessions; LCLS Workshops
  • October 18 - Soft X-ray Science with the LCLS Workshop

Conference postcards and registration will be announced in June. Start to encourage members of your group to think about submitting abstracts for poster presentations (the program is drafted and there will not be any call for contributed talks this year).

ACTION: Users are encouraged to nominate candidates for the awards to be presented at the annual meeting and to identify SSRLUO members willing to serve on selection committees (Wayne, Art and Stephane volunteered, and Glenn and Monika were also suggested as volunteers):

  • William E. Spicer Young Investigator Award Nominations due August 1
  • Melvin P. Klein Scientific Development Award Nominations due August 1
  • Farrel W. Lytle Award Nominations due August 15

(the SSRLUOEC is the award selection committee and a meeting will be arranged in late August)

Jo Stöhr attended the meeting to discuss the report from the BES Program Review of SSRL which was held in January. The report was very positive overall. The reviewers recommended separating the SSRL Proposal Review Panel (PRP) from the Scientific Advisory Committee (SAC) and establishing terms for the advisory committee. SSRLUOEC members stated their preference for continuity on the PRP to ensure that proposals are reviewed consistently year to year. The report also recommended updates to the SSRL user proposal database and web interfaces, which are underway. The report required that user publications be reported to the DOE by beam line in the future (many SSRL users use multiple beam lines to conduct their experiments). ACTION: The SSRLUOEC requested the ability to query the user database so that they are better able to identify and communicate electronically with users by discipline, by techniques used, or by geographic location.

Jo Stöhr, Uwe Bergmann and Donghui Lu discussed a new project, called PEP-X. Looking beyond SPEAR3, SSRL is interested in exploring exciting new opportunities by using the existing PEP-II storage ring to create the ultimate synchrotron. Jo invited and challenged SSRL users to help dream big to make the scientific case for this long-term vision, specifically in define spectacular experiments that could not be done anywhere else. The SSRL Accelerator Physics group is working on a white paper which will outline critical parameters, technical specifications and opportunities for PEP-X (to be available shortly). The new source would be housed in the existing 2.2 km PEP-II tunnel and would utilize many of the existing PEP-II accelerator components and systems. PEP-X could be 3-4 times higher brightness than SPEAR3 and10 times brighter than the new NSLS-II. PEP-X could have an order of magnitude higher average brightness and flux in the 1- A° wavelength range than any existing or future storage ring planned for the next decade around the world. This enhanced capability will enable new science and faster data acquisition while benefiting from the inherent stability of a storage ring light source. Partial lasing in a 50-100-m ID may be possible at energies <~350 eV.

Potential experiments could include imaging, energy related spectroscopy, spectromicroscopy, time dependent spectroscopy, scattering, high energy experiments (50-70 KeV), or experiments which could complement the LCLS (nanosecond to second timing; faster detectors, pump, pulse (20 picosecond, etc.). To help prepare the scientific case, Uwe suggested that users review documents prepared for other recent projects:


PETRA III will be a new high-brilliance synchrotron radiation source on the DESY site in Hamburg-Bahrenfeld. For a total investment of 225 million , the existing storage ring PETRA will be converted into one of the most brilliant x-ray sources worldwide. Conceptual design started in 2002, final approval of the project in May 2005, the reconstruction of the storage ring started on July 2, 2007, and PETRA III will commence user operation in 2009.

DORIS. The 4.5 GeV storage ring DORIS III at DESY in Hamburg is a dedicated synchrotron radiation source with 9 wiggler/undulator insertion devices and several dipole beamlines (36 beamline stations). The stored current is 140 mA of positrons in 5 bunches with a typical lifetime of 10 to 18 hours. The radiation in the extreme ultraviolet and x-ray regime is used in a broad range of applications from biology and chemistry to material science.

CORNELL. Cornell University and Jefferson Laboratory physicists have been studying the properties of a new type of synchrotron radiation machine, called and Energy Recovery Linac (ERL), based on a superconducting linac and a one-turn return arc (like a storage ring). A 5 to 7 GeV, 10 to 200 mA ERL machine could produce electron beams of a few microns diameter with very low emittances (8 to 100 pm) in both the horizontal and the vertical planes. Small gap undulators up to 25 meters in length can produce ultra-high brilliance x-ray beams with many desirable characteristics, including: transversely coherent, diffraction-limited hard x-rays of very short (~20 fs to 2 ps), frequent (1.3GHz) pulses, with no limits on beam lifetime and very flexible modes of operation.

ACTION: Users are asked to send us their ideas (all input welcome from a short elevator talk to a more flushed out proposed experiment). Users are invited to join the teams which are being formed to start exploring opportunities at PEP-X for the time period 2015-2020. Further discussions/workshops will likely be held in the next few months. For more information, contact Uwe Bergmann (Hard X-rays), Donghui Lu (Soft X-rays), or Hiro Tsuruta (Structural Biology). Jo Stöhr plans to give an update on PEP-X at the annual Users' Meeting and workshops October 15-18, 2008.

Users asked about plans for improved detectors and how detectors would be impacted by higher current operations. Uwe suggested that spectroscopy and scattering users get more organized and vocal in communicating their needs and that by coordinating with other users communities/committees, users could help push for development of better detectors (e.g., K-Tek single element, silicon drift detectors in photon counting mode, 30-element silicon drift detector, multi-element detectors). ACTION: It was suggested that a detector advocacy committee could be formed to discuss and potentially help coordinate detector development in conjunction with other user facilities and/or companies.

Several announcements were made related to the new LCLS website which recently launched. LCLS AMO Proposal Writing Workshops scheduled June 2-3 SXR Consortium meeting June 6-7 (this is a closed meeting for consortium members to discuss logistics of a soft x-ray instrument to built for use on the LCLS, but an open meeting/workshop is planned in conjunction with the annual Users' Meeting.) PULSE Ultrafast Summer School, June 17-20 LCLS XPP Proposal Writing Workshops scheduled June 20-21

The meeting adjourned at 4:15 pm.

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