1. UITF Conduct of Operations Review
UITF Review #3
Extras
Matt Poelker
Wednesday, April 24, 2019

2. The QCM Predictions from Haipeng Wang
There are no plans to operate the 7 cell in field emission regime
16 MV/m x 0.7 m = 11 MeV max beam energy
We plan to operate QCM at 5 MeV for CEBAF and ~ 8 MeV for HDIce
UITF Conduct of Operations Review - Status

3. Maximum Current through the QCM?
We installed a 4.4 kW klystron to drive the 7-cell cavity
Based on measured Qo, Haipeng calculates we can accelerate maximum current uA at 10 MeV
UITF Conduct of Operations Review - Extras

4. What about for lower beam energies?
If one tries to accelerate more current, beam energy will “sag”
P = I * V
I = P / V
Haipeng Predictions, with 4.4 kW klystron
UITF Conduct of Operations Review - Extras

5. Gun HV power supply UITF dc HV photogun
Glassman HV, 450kV and 3mA capable
Operating restrictions: HV and current limit setpoints – defense in depth
Similarly, we will assign software limits to the rf drive of the 7-cell cavity
UITF Conduct of Operations Review - Extras

6. CARM locations CARM probes are shown by green squares on the maps.
CARM RM801
3 probes, all gamma, located at Cave-1 roof ("mezzanine") penetrations near the gun and QCM.
CARM RM802
3 probes, all gamma, located at (1) cave 2 entrance gate, (2) cave 2 west wall adjacent to physics workshop, (3) top of stairway at northeast corner of cave 2
CARM RM803
1 gamma probe, located in the control room
RAPID ACCESS RM803
This is a non-PSS interlocked unit, currently has 1 gamma probe and 1 neutron probe, both inside cave 1.
UITF Conduct of Operations Review - Extras

7. Ambitious Schedule: what lies ahead in the next 12 months
New Gun operation at 200kV
Repair HDIce
Functional MeV beamline (engineering support)
Reviews (COO and ARR)
Commission Accelerator: write the plan
Validate functionality of QCM (to be installed at CEBAF May 2020)
HDIce ERR
Four HDIce run periods!
UITF Conduct of Operations Review - Extras

8. BLM locations
UITF Conduct of Operations Review - Extras

9. (Songsheets = UED) MeV beamline
UITF Conduct of Operations Review - Status

10. Shielding Assessment Table (old table)
See updated version
UITF Conduct of Operations Review - Extras

11. Normal Operations Beam Loss/ Termination Point Beam Loss Condition
(Watt)
Duration
Frequency
Duty Cycle*
Exposure Location
Dose rate
(mrem/h)
Dose/Event
(mrem)
Annual Dose**
Notes
High Current Mode
Lower beam line opposite maze 1
8 hr
Continuous
0.09
Cave 2 entry gate
0.006
0.008
1.1
Represents 0.1% of the beam power (100 nA) for high current operation (100 μA); assumes robustly shielded dump(s) and 100% occupancy.
Cave 2 roof is HRA - not routinely occupied. Cave 1 roof is RCA, assumed 100% occupancy.
2nd floor office
0.010
0.016
1.8
Source lab
<0.001
<0.008
<0.2
Cave 2 roof 3 24
N/A
Cv 1 roof boundary
0.8
6.4
144
Low Current Mode
HDICE Line
0.05
0.36
All -
Conditions all bounded by 100 nA
60 min
2/day
West wall
<0.005
<0.9
Full loss (100 nA) in low current mode (beam loss, or delivery of tune beam to F-cup)
Roof is posted radiological area and not routinely occupied
0.003
0.54
0.001
0.18
He Vent/C2 roof 4
Gun Test Mode – Not Accelerator Operations
keV Mode
3000
4 hr
 Few/year
<0.4
<1.6
<6.4
Drifting mA through QCM (off) to FC (without shield)***
1350
Few/year
0.5 2 8
Drifting mA through QCM (off) to FC (without shield)***
* Assumes 900 hours operation/y; 20% high-current, 80% lo-current mode (25% of low current running at 100 nA)
** Non-RCA design goal is 10 mrem/y, RCA design goal is 250 mrem/y
*** Routine condition is beam delivery to a shielded Faraday cup. Dose rate shown is for off-normal event upstream of FC. CARM probe at entry gate protects.

12. Beam loss/ termination point
Accident Conditions
Beam loss/ termination point
Beam Loss Condition
(Watt)
Duration
Exposure Location
Dose rate
(mrem/h)
Dose/Event
(mrem)
Notes
Lower beam line
opposite maze
3000
15 min
West wall 12 3
Worst plausible overcurrent condition at full energy ( uA).
Includes assumption of simultaneous, complete beam spill in lower beam line (may not be credible).
2nd floor office 30
7.5
North wall
2.4
0.6
C2 Roof (over loss point)
9000
2250
C2 Roof (He vent)
750
C1 Roof boundary
2400
600
Carve 2 access gate 18
4.5
HDICE Line
1000
<2
<0.5
Overcurrent condition (100 uA) in low current mode; loss point in HDICE line, vicinity of target
0.75 1
0.4
He Vent/roof
4000
<1000
<250
Cave 2 access gate
0.1
4200 2
0.5
Worst plausible overcurrent condition – beam loading degrades gradient to 5 MeV, current is 840 μA. Beam is lost in lower beam line.
C2 roof (over loss point)
10,000
2500 9
2.25
All cases result in integrated dose < 15 rem.

13. Accident Conditions (cont’d)
Beam loss/ termination point
Beam Loss Condition
(Watt)
Duration
Exposure Location
Dose rate
(mrem/h)
Dose/Event
(mrem)
Notes
QCM Exit
3000
15 min
West wall (cont. room)
< 0.9
< 0.23
Worst plausible overcurrent condition at full energy ( uA).
Includes assumption of simultaneous, complete beam spill at CM exit (may not be credible).
Above cont. room
< 30
< 7.5
Roof
< 90
< 23
Roof penetration*
40,621
10,155
Cable trench (cont. room)**
120 30
Vent duct exit
< 15
< 3.75
4200
< 1
<0.25
Worst plausible overcurrent condition – beam loading degrades gradient to 5 MeV, current is 840 μA. Beam is lost at CM exit.
Values conservatively scaled from same accident in cave 2.
< 33
< 8.5
< 100
< 25
45,090
11,272
133 34
< 17
< 4.5
* Based on analytical methods, modeling expected to reduce value significantly.
** Results without shielding
All cases result in integrated dose < 15 rem.