Minutes of the Orion Technical Meeting: Sept. 27, 2000


 Location: Room 144D (Beige Room),

           Admin. and Engin. Bldg., SLAC

 Present:  Robert Noble, Dennis Palmer, Robert Siemann, Dieter Walz

 Minutes recorded by: Robert Noble


 1. Meeting time: 

      Future meetings will be on Mondays, 10 AM in the Beige Room

      (Room 144D) in the A&E Building (Bldg. 41) at SLAC.


 2. Discussion of the next steps in the Orion project:


    - The assumption is that we will receive by October 30 an NSF

      invitation to submit a full proposal due January 26, 2001.

      Award announcement will occur by August 1, 2001 (10 months

      from now) at which time we start construction of Orion at

      the NLCTA.


    - Before construction start, the Orion project will require

      a baseline design, a final Work Breakdown Structure, Schedule

      and Cost Estimate. This enables all participants to understand

      their tasks and resource needs.


    - A short Technical Design Study (TDS) with contributions from

      the various participants in the collaboration is a proper

      vehicle to address the above issues. R. Noble will act as

      editor and begin contacting collaboration members to act as

      writers. A draft "Table of Contents" has been placed on the

      Orion website (http://www-project.slac.stanford.edu/orion)

      within the Collaboration's special page (access by Collaboration

      members only via password available from R. Siemann,

      siemann@slac.stanford.edu). There may be more subsections at

      Level 3 than this draft table shows depending on text supplied

      by the writers. A TDS document of about 50-75 pages is thought

      to be adequate, so contributions from individual writers should

      be brief and to the point. The target date for the first TDS

      draft is November 17, 2000. Much of the material generated for

      the TDS can be used in the NSF proposal.


 3. Roundtable discussion of Orion design assumptions for the TDS:


    - The Orion RF Gun is assumed to be a 1.6 cell, S-band (2.856

      GHz), emittance compensated photoinjector, based on the well

      known BNL/SLAC/UCLA design, and driven by a frequency-tripled

      Ti:Sapphire laser in a Class 10K clean room. Whether the new

      injector is physically interchangeable with the present X-band

      NLCTA gun or intalled as one leg of a Y magnetic switch

      (dipole) depends on a beam dynamics study as well as reaching

      agreement with the NLCTA management.


    - The Low Energy Extraction Line at 50 MeV will leave the NLCTA

      enclosure at a 20 degree angle, necessitating the boring of a

      beampipe hole through four of the interlocking shield blocks.

      A beam physics design will be performed to confirm that a

      beamline with quadrupoles on either side of the wall can

      transport the beam properly.


    - The Laser Room 1 layout shows it to be 20 feet by 40 feet,

      which is large for the compact, commercial laser. It was

      suggested that we keep the room oversized to provide added

      lab space for other Orion work and upgrades. Laser Room 2 for

      experimenters will be expanded in the design to allow for up

      to two laser systems with separate enclosures. The interlock

      system will be designed with sufficient flexibility to allow

      personnel access to lasers not in use for beam-on experiments.

      The laser room at Bldg. 407 was cited as an example to use

      for estimating floor space and utilities.


    - An Experimental Staging Area for users will be needed in the

      vicinity of the experimental halls. Experimental equipment

      can be mounted to support girders and tested prior to

      installation in the halls. A new SLAC lab building is being

      planned for the area immediately northeast of End Station B,

      and R. Siemann has requested Orion space there from

      S. Williams, SLAC Experimental Facilities Dept.


    - The present concept for experimental operations in the Low-

      Energy Hall envisions space for three installed experiments

      on the floor, but only one taking beam during a run period

      lasting a few days. Beam would thus be time-shared between

      the experiments with one taking data and the other two

      analyzing data and preparing for their next run. This

      arrangement simplifies the Control System to one appropriate

      for single-mode operation and no fast beam sharing.


    - In order to insure that there is no interference with the

      Laser Room 1 or the 20 degree Transfer Line to the Low Energy

      Hall, NLC management will be consulted on their need for

      floor space inside End Station B for the so-called "8-pack"

      RF System Test.


    - A critical part of the Orion TDS will be an estimate for

      water and power utilities. As the Laser Systems, RF System,

      Transfer Lines and Experimental Halls are defined, a power

      and water supply budget will be tabulated with the aid of

      the SLAC engineering staff.


    - D. Palmer, D. Walz and R. Noble will make a fact-finding

      trip to the Accelerator Test Facility at Brookhaven National

      Laboratory on October 26 - 27, 2000 in order to learn about

      that facility's design, utility and space requirements,

      operational procedures, and construction and operational