1. +-- Collider Front end- Balbekov version
Test
+-- Collider Front end- Balbekov version
David Neuffer
Fermilab

2. Outline +-- Collider Single bunch Collection and cooling Scenario
Critical components
+, - Capture
Capture large phase space
 - Cooling
Cooling of large phase space, 6-D cooling
By large amounts

3. References NuFACT03 talk
Accelerator Advisory Committee talk (November 2003)
Mucool 245, 272, 276, 277 notes
PAC 1999 (Li lens Channel)

4. Summary

5. First +-- Collider cooling scenario -Balbekov
Complete simulation
obtains ~0.05 /p
PD-proton source
 TS Target Station 
PR phase rotation (36MHz)
40m, single bunch
BC –Bunch Compressor
36MHz ring cooler (1.75T),
,rms: 17  7mm, L,rms: 300 30mm
 RF- RFOFO Ring Cooler
200MHz ring cooler (~3.5T)
,rms: 7  2.5 mm, L,rms: 30  3mm
 LL – Lithium lens cooler
 10 T
,rms: 2.5  0.5mm

6. Collider Cooling Scenario
Nearest to “complete” cooling scenario for +-- Collider …
Balbekov 2003

7. Producing and Capturing 
Collaboration baseline:
16-30GeV p-beam on
Target (Hg-C) immersed in
201.25 T solenoid, taking
~250 MeV/c 
? …
Rf: MHz,
6.37 MV/m
Capture in 1 bunch

8. RFOFO ring cooler performance
Transverse before and after
Cools longitudinally more than transversely
Longitudinal cooling not fully used in scenario
E-ct before and after

9. Compare 2003 and 1999 Li coolers
2003 – short cells, “small” phase advance/cell
200MHz rf, 15MV/m
10T, r= 1.2cm L=0.13m β* = 4.25cm
Cools transversely to ~5mm
Large longitudinal dilution
2.6m cells, 90m channel
1999 – Long cells - 180º longitudinal phase advance/cell
800MHz, 30MV/m rf
Up to 20T, 0.8cm lenses, 1.8m long
Cools transversely to ~2.5mm
Smaller longitudinal emittance and dilution
50m long -- 5 cells

10. Balbekov 1999 Li lens cooler

11. Final Li lens Cooler ??? Need to cool T from ~0.5mm to ~0.1mm
Stronger focusing Li lens ??
10T  20 T
Smaller aperture
Stronger longitudinal Focusing
30MV/m , 805MHz
Problems
Chromatic effects
Matching

12. Critical R&D needed Push low-frequency gradients
6MV/m  ?? (~30 MHz)
12MV/m  ?? (~200 MHz)
Injection/Extraction Kickers
Improve optics (acceptance, …)
Li lens technology
Maximal field 20T+
Gradient 1cm or less
Length ??
lifetime (110  60Hz ??)