1. 12 Steps to a Cooler Design
D. Douglas

2. Concept
Apply the same system engineering process that was used to design/build the IR Demo, IR Upgrade, UV Demo, reconfigure CEBAF for CEBAF-ER and the IR Upgrade for the DarkLight aperture test
Balance risk & technical maturity of available methods to provide a cost-effective & robust system
no magic, no miracles: rely on demonstrated solutions/technology
when methods don’t exist, identify challenge & provide R&D plan, risk assessment, and workaround
Deliverable: feasibility assessment and actionable cooler design report in < 2 years
“actionable” => informs down-select
List of components, locations, tolerances, sensitivities, cost ± 10%

4. “12 Step Program” A framework for making design choices…
Basic system engineering: establish requirements, break design down into smaller bits.
Implement configuration control from outset!
Cooling requirements drive design
Define source performance
Constrain accelerator architecture
Accelerator architecture analysis
Reveals challenges (“miracles”)
Provides opportunity for cost/performance optimization
Reuse existing methods, technology, designs?
Can organize activities as a sequence of trade studies & design tasks
“trade study” = performance/risk/cost assessment of available solutions + down-select to optimum path forward

5. 12 Step Breakdown for Cooler Design
establish cooling system requirements
energy, current, charge/bunch
emittance, phase space configuration ("match") - transverse and longitudinal
cooling rates for magnetized vs. non-magnetized beam
architecture trades & cost/performance optimization
linac vs. ERL vs. linac + CCR vs. ERL + CCR (cost optimum)
choice of RF fundamental
informed by required bunch length, need to get beam into/out of CCR
source trades
thermionic, photocathode, magic... X RF, DC
magnetized/nonmagnetized

6. beam transfer system trades and design
injector design
merger design
linac design
Note: initial results from design iterate indicated can't get required brightness through linac, at least at 750 MHz x 1 cm rms bunch length;
don't know what happens - at least longitudinally - when going to longer bunch and/or lower frequency, though notionally transverse "should get better"
beam transfer system trades and design
bunch to bunch, bunch train, full ring (RF loading probably precludes this)?
pulsed kicker vs. RF separator based?

7. develop CCR design - with space charge, CSR, microbunching
simulation of spent beam after cooling
recovery transport design, if ERL is used
S2E with cooling simulation
sensitivity studies, tolerance specifications
Provides basis for cost analysis & engineering design
Informs project down-selection process