Meetings are held in Room 84, Trailer City on Thursday at 1:30 P.M. Note this change!

ATTENDEES: S. Benson, G. Biallas, C. Bohn, D. Douglas, E. Feldl, L. Harwood, K. Jordan, W. Merz, C. Murray, M. Wiseman,

Decisions/Comments:

To use the power supplies within their high resolution and good stability range and not compound the effect of safety factors, while the DIMAD is for a nominal energy of 42 MeV, the dipole string will be designed for 45 MeV (Assuming a 10 % over specification cryomodule) at a current of 217 A. Maximum current from the power supplies is 220. (Editor's note: According to W. Merz, an additional 5% more current is available with some work if it is required.)

L. Harwood claims it will be difficult or impossible to match the IBdl values of the families of dipoles at a single current to the tolerance required by D. Douglas' specification. This is especially true of the saddle coil style Optical Chicane Bends.

It was decided at the vacuum meeting that we would use stainless steel vacuum chambers throughout because of the higher probability of success the first time and less probability that it will require development.

D. Douglas announced that the shunts will be applied to each of the 180 Degree Bends, to each of the sets of four Reverse Bends at each end and to each of the sets of four Optical Chicane Bends in a Chicane.

Provide magnetic based phase adjustment over a 400° range by using ganged air core dipoles at the entrance and exit of the 180 Degree Bends. Move the flanges further away on the beam tubes to provide room for the correctors.

Vacuum system meetings are being held on Wednesday at 10:00 in Rm. 84, run by L. Dillon-Townes.

P. Kloeppel is doing analysis of the various dump configurations.

Action Items:

J. Parkinson/C. Murray/B. Yunn - Maintain latest layout/ define the vacuum tube at all discontinuities, refine impedance analyses and write the Tech. Note. Definition of discontinuities in process. Continuing

C. Bohn - Establish a clean statement of the energy range of the machine. Status: Need help from Biallas/Harwood to plot cost vs. maximum energy for the magnetic optics. Division Leadership Group wants to see this data. Second price estimate received. Presentation to M& due next Thursday.

D. Douglas - Check if the existing QJs can be used in the new injection line. No news

G. Biallas - Get the BT contracts signed. G. Biallas has to check task list.

T. Siggins/K. Jordan - Review proposed Shielded Viewers for vacuum construction properties. No progress.

E. Feldl - Make the prototype weak QB. Complete. Awaiting repair of card in CAMAC module and another two weeks of testing required on the quads of the NP Accelerator.

G. Biallas - Define the trim quad for start of engineering design. No progress.

G. Biallas - Start definition of a girder for the wiggler, diagnostics and quad telescopes that maintains position of the elements within 50 µm (0.002 in.) during change-out of the wiggler. No progress.

L. Harwood - Determine if placing additional dipole(s) around the first dipole of the dump chicane after the cryomodule is the best method of bending pulsed 42 MeV beam into the dump during cryomodule phasing. Being considered.

D. Douglas - Check the width of the beam in the 45° either side of the 90° point in the 180° Dipoles. No progress.

New Action Items:

G. Biallas/L. Harwood - Provide a good value for field enhancement factor for the style of magnets we are anticipating. Verify the K value of 0.45 that D. Douglas uses in his optics calculations.

C. Bohn - Have B. Yunn establish the vacuum specification for the remainder of the vacuum system using the criteria of ion trapping.

G. Biallas - Examine the categories on the Web and propose alterations.

New Action Items from the Diagnostics/Commissioning Meeting:

Resolve the diagnostics requirements of the 180 Degree Bends.

Reverse the field on the dipole at the Injector Dump to deflect the beam in the opposite direction. Proposal is preferred. Passed to Diagnostics Meeting to establish effect of focusing ion dump diagnostics.

Completed Action Items:

G. Biallas/J. Parkinson - Do the appropriate calculations and get Sign-off on relaxed vacuum requirements near cryomodule by R. Sundelin & P. Kneisel. We need the hard interlock values for closing valves. In a meeting with R. Sundelin, M. Wiseman and J. Parkinson determined the vacuum specification near the cryomodule should remain at the 10-9 Torr level. This requires baking and some differential pumping. Precipitators were recommended pending the analysis of the precipitator removed during the shut down. Complete.