Injector Test Stand Meeting Minutes of July 23, 1996

and Reports of July 26, 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.

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

ATTENDEES: S. Benson, C. Bohn, L. Dillon-Townes, F. Dylla, D. Engwall, J. Fugitt, K. Hovater, K. Jordan, G. Krafft, D. Kehne, R. Legg, W. Merz, G. Neil, C. Rode, M. Shinn, T. Siggins, M. Wiseman

General Announcements:

None

Decisions/Comments:

F. Dylla commented that the test stand project has not met its deadlines. Meeting the final operation deadline is extremely important. The ITS is the cornerstone of the FEL project, a Jefferson Lab high priority. We expect some setbacks in the things we know and mostly in the things we don't know. Lately we have been beset with a series of Murphy's law events. Our only course in the face of the critical time schedule is to be ready to handle setbacks without breaking our stride. 1) Work in parallel. If there is a series of items that you think only you can do, stop the series string now and get other people to do some of the tasks in parallel and see that they do them right. 2) Analyze the back up equipment and supplies the ITS needs. Since the main machine is authorized, use that money to purchase now the equipment you will need anyway and that backs up the ITS. A $10000 item is not worth a two week delay. 3)Anticipate an catinate. Progress should be like a relay race where the baton gets passed on the run. We shouldn't be stopping to get the next phase going, the contracts, internal and external should already be in place to continue progress as sub tasks get done.

J. Preble put in a word that every day managers are assaulted with priority one's from not only the CEBA but Admin and other parts of the lab. Life is difficult.

J. Fugitt commented that our matrix organization breeds less ownership of tasks. The result is

F. Dylla said we have two major tasks facing us in the short term, Starting the Transverse Experiment with the beam after the bake and getting the new ceramic stack in time for the start of the Longitudinal Experiment. We will practice the above styles of operation on these tasks.

Safety Action Items:

The Cryomodule Test Cave needs to be brought up to present standards of redundancy in order to be usable with our 50 kW RF power. That group may need some of our help.

New Safety Action Items:

None

Completed Safety Action Items:

Response to inadvertent access to the laser enclosure.

Action Items:

T. Siggins/D. Engwall - Get the gun and line baked and get the Experiment running. The response to our problems found since the back is: 1) Vacseal the very small leak in the five way cross. 2) substitute longer studs into the VAT Valve to Light Box connection to avoid opening the seal up during a bake and add a retorqing of the flanges after bake to the procedure. 3) Add an RGA to the beam line for leak testing. 4) Study and respond to the vacuum housekeeping implications of the leaking VAT valve. 5) Heating the GA Crystal and recesiating to again check for cesium response. (May indicate problems with the Cesiator.) 6)

Determine the need for additional personnel required to match or beat the Schedule. We have 1 A Trim Cards. Get from J. Preble and J. Parkinson a two man crew to help get the bake going.

T. Siggins - Write the tricks of polishing learned at SLAC. No action.

G. Biallas - Get cleaning started in the area on a regular basis. G. Biallas will set up a roster for cleaning in the future. No action.

G. Biallas - Define Nomenclature document Definitions have to get to T. Hassler. No action.

J. Susta/M. Wiseman - Alter the permanent LCW system for the Klystrons such that the pressure remains low and put a relief in the waveguides in case a circulator window breaks. Klystron are plumbed with low pressure LCW. The waveguide relief is being assembled.

G. Biallas - Finish the LCW System: Flow & Temp reading, Level indicators, UV Lamp - UV lamp needs to be commissioned, full qualification walk through needed

D. Kehne - Have simulations or bracketed simulations of the 250 keV projected initial running case for the Gun. D. Kehne's is in process. He is also proposing a n alternate to use the Longitudinal apparatus to perform the high voltage portions of the Transverse experiment.

K. Jordan/S. Benson - Failure analysis for the 10 MeV beam handling. No action

M. Shinn - Put phase noise documentation on the web. In process.

M. Shinn - Get HeNe at low power onto cathode. In process.

All - general cleanup after bake. Checkout systems, straighten out cabling. Partially done.

R. Walker - get Chopper LCW hooked up. Positioning of the skids in process

D. Kehne - Publish the straw man for the 10 MeV Experiment . The straw man is complete,; he will get it to Bob Legg.

G. Biallas - integrate the new experimental schedule developed by Bob Legg into the main schedule. In process.

New Action Items:

G. Biallas - Set up a micro schedule for stack completion.

Completed Action Items:

R. Walker - send out MO for re calibration and provide replacement. Complete.

K. Jordan - move Digitels into control room. K. Jordan will supply roll-around, short cabinet for the enclosure. It will contain two New Digitels he bought for the IRFEL. Definition of fix complete.

L. Dillon-Townes - design transition radiation mirror for dump. Complete.

Individual Reports of 7/26/96:

G. Biallas:

This is the plan for eliminating the problems with the insulators.

1. Minimize the field emission. We will build another stem that we will coat with Calcium Fluoride or other proprietary material of FM Technologies Co. These reportedly lower the Field emission by 6 to 8 orders of magnitude.

2. We will get five more insulators made with 97.6 % Aluminum Oxide. This is the ceramic used in the original 400 kV Gun.

3. The resistive coating on the ceramics will be done by ion implantation at Berkeley. The original coating is an expensive back-up.

4. We will attempt of produce a lossy ceramic-like shield to intercept electrons from field emission for use in the present gun( if we can get it done on time) or for the next ceramics. One candidate material is Silicone Nitride made by FM Technologies which can be made to have volume resistivities down to 1 Ohm cm.

5. We will investigate getting ceramics made out of materials such as Zircon that have three orders of magnitude lower Volume resistivities than Aluminum oxide.

The preparation for the second bake continued during the week starting with plugging the leak in the five way cross with vac seal and ending with a wrap with thermocouples and heat tape. However no cesium response was seen from the crystal at weeks end. A bake can't proceed until an adaquate response is seen.

L. A. Dillon-Townes:

500 keV experiment :

Transverse Experiment:

-Aperture has been put into the brazing que.

10 MeV experiment:

- Brazing vendor visit planed for Dump brazing and Ceramic stack brazing review.

-Reflective mirror for the drift tube diagnostics is in the shop.

- Assembly drawings being processed.

- 32 gal water recover tank ordered.

J. Fugitt:

Completed low power testing of the HOM filters. They both have a slightly marginal VSWR at about 1700 MHz. Plan to do 50 KW power test next week.

Continued installation of 50 KW HPA equipment

Have the buncher cavity vacuum tight and couplers installed. Frequency and coupling are good. Next task is full power testing.

M. Shinn:

Was successful in interfacing the HP8561E spectrum analyzer to a computer, in order to get high quality plots for a future publication. Phase noise data taken using the vendor's MO showed somewhat lower measurements ( 0.7±0.1 ps vs. 1.0 ±0.2 ps) than the data taken the previous week. This appears to be due to a slight detuning of the cavity length. R. Walker and I worked on retaking phase noise data with the external MO and divide-by-40 units, but were unable to achieve stable locking. Measurements will resume after Dick replaces the MO and the laser service call is complete.

Arranged to have Kyle Frische, of Coherent Laser Group, out to do a thorough check of the laser.


Enclosures:

ITS Schedule for 7/30/96