Injector Test Stand Meeting Minutes of December 17, 1996

and Reports of December 20, 1996

AGENDA:

General Announcements

Action Items

Progress Toward the Milestones of the enclosed schedule:

NOTE: Meetings are held every Tuesday in CEBAF Center, Room #A110, at 11 a.m., unless otherwise notified.

ATTENDEES: M. Augustine, S. Benson, G. Biallas, C. Bohn, D. Guilmet, K. Jordan, R. Legg, G. Neil, J. Preble, M. Shinn, T. Siggins, R. Walker, M. Wiseman

NOTE: A reminder to all principals to submit a brief weekly progress to D. Gilchrist each Friday by noon

General Announcements:

There will be a safety review of the Injector Test stand safety systems by the RCG at 1:00 today.

Decisions/Comments:

The safety review sponsored by the RSG went well

We will change out the valve between gun and line when it is convenient

Safety Action Items:

K. Jordan - Add a third sensor for ODH to the High Voltage room. Will be done during Change-over.

J. Fugitt, C. Reese, K. Jordan - Review the safety effects on our systems of running only one HPA for work in the Cryomodule Test Cave. In process but not needed until at beam is used in the cryomodule. No progress.

Rich Hill - Label the gas lines with media and pressure - No progress

G. Biallas - Provide safety hardware for the shelf by the LCW system. Not needed. Personnel will not go in that region except with a harness.

New Safety Action Items:

None.

Completed Safety Action Items:

RCG - Review the beam containment policy and the Machine Protection System during October. R. Legg reports he is waiting for RCG action. Complete.

Action Items:

G. Biallas - Make a new ceramic stack and make a new cathode support tube with a anti field emission coating. See weekly report by G. Biallas.

Determine the need for additional personnel required to match or beat the Schedule. None

G. Biallas - Finish the LCW System: Flow & Temp reading, Level indicators, Full qualification walk through needed. Remove two carbon steel pipes inside LCW system. Walk through complete. several items need fixing.

K. Jordan/S. Benson - Failure analysis for the 10 MeV beam handling. Required by Dec. 1. No show stoppers showing up.

R. Legg - Write the OSP for the 500 keV Experiment with chopper on and cryomodule in the cave. and for the 10 MeV Experiment. Ready for sign-off.

M. Shinn - Define a secure procedure for turning on the Drive Laser from the control computers. No action.

J. Preble - Get the ceramic windows finished for the December Quartercryomodule tests. One is on hand. Promised by January 15.

K. Jordan - Design a new viewer system with stable cameras and appropriate windows. At the same time avoid stray light back to the Cathode. Being done during change-over.

R. Walker/K. Jordan - Substitute stainless steel for the aluminum filament supports on the harps. Still needs work .

M. Shinn - Perfect the optical chopper before the next CW run. Needs refinement for more demanding runs. EO1 is in place. Continued good progress.

G. Biallas - Get drawings prepared of the configuration of the gun for the control room and a summary package that can be sent to others as an explanation of what the gun is. No action.

L. Dillon-Townes - Get the core for the solenoid before the Quartercryomodule for the 10 MeV Run. Drawings need sign-off.

G. Biallas - Characterize the raster magnet for 10 MeV and measure several QJs that need alignment bushings. in process.

New Action Items:

D. Kehne - See if spectrometer dipole for 10 meV needs a field clamp and saddle coils.

K. Jordan - Perfect a way to set the viewers for the 10 meV Experiment.

New Action Items for the Diagnostic Mtg.:

None

Completed Action Items:

K. Jordan/M. Shinn - At Change-over, install a method of characterizing the optical transport line configuration at any one time and conveying the information to operators. Complete.

L. Dillon-Townes - Convene change control board to make a recommendation on the Differential Pump Station and the question of baking the after Cryomodule line in both the ITS and the IRFEL after doing the necessary calculations of assumed gas load. Review continuation on Tuesday, Dec. 17 at 1:00 pm. Complete. We will eliminate electrostatic Precipitators and substitute Differential Pump Stations.

G. Biallas - Get Schedule up to date. Complete.

Individual Reports of 12/20/96:

G. Biallas:

The new stack/Cathode Support Tube:

Our measurement apparatus that determined the resistance of the ceramics in a vacuum was faulty for the readings that indicated very high resistances. Subsequent measurements with a new resistor in the Keithly Diode Box in series with the Electrometer revealed resistances in the order of 5 & 6x10^11 ohms on two ceramics with projected currents at 250 kV of around 600 na. This value was judged marginal by C. Sinclair in the face of Fowler Nordheim calculations that indicate field emission currents in the order of µa. because the voltage gradient across the ceramics would be distorted. We will make a decision on what to do with the ceramics after results from the full scale ion implantation project are known.

Measurements of the ion implanted samples indicated that a dose of 6x10^16 per cm of platinum ions had the potential to create ceramics with resistances (linear with respect to voltage applied) of 1 to 6x10^11 ohms. This was welcome news in the face of the not well characterized spray coating. With these readings, we feel confident that L. Phillips and T. Siggins could create two ceramics for the new stack and they were dispatched to Lawrence Berkeley Lab on January 2.

FM Technologies finally came through with a quote to cover the entire Cathode support tube with their anti-field emission coating and the tube was sent to them on Christmas Eve. They projected delivery in 6 weeks.

The summary is that all our parallel paths to get a gun that will go to 350 kV (or even 500 kV) seem to be converging to a solution at about the same time, the end of January. Bob Legg decided to start a bake now to get some experience with the new line before we do that fix.

R. Walker:

The waveguides to the Quarter cryomodule are nearly completed. A few additional parts are being made in the Machine Shop. The waveguide sections for the Chopper are installed. Chopper cables and water skid need to be installed.

A replacement valve for the Buncher water skid is late. The control electronics needs to be reassembled and tested. A M-460 CAMAC card needs to be repaired so the cavity water temperature can be read.

New downloadable code and screens are still at test for the Buncher. The Chopper code will be part of the Buncher.

The following is the status for the ITS Test Cave tasks:

a) Quarter cryomodule is positioned off-axis awaiting the correct warm windows.
b) Diagnostic chamber needs to be leak tested.
c) New aperture was installed and is ready for alignment.
d) Stainless steel harps were made, installed, and aligned.
e) Stands for 10 Mev experiment need to be degaussed.
f) Top roof block was moved to reduce a crack in cave ceiling.
g) RadCon is to install a steel tee shaped bar on cave roof to close the above crack.

Enclosures:

ITS Schedule for 1/7/97