1. Cooling channel issues U. Bravar Univ. of Oxford 31-Mar-2004

2. MICE channel plots

3. G4MICE requirements What needs to be done to make these plots: Virtual planes user defined z-location Interface with ecalc9f to calculate  n Standard input beam to achieve  15%

4. Input beam Define one standard (e.g.   = 6,000 mm mrad &   = 33 cm, start in middle of upstream spectrometer) Save generated beam in file Beam defined as x-p x, rather than x-x’ Place coils upstream of first tracker Replace `beta = 420’ in G4MICE default (Ability to software-select desired beam in upstream spectrometer)

5. Why do we need a standard? Example: Study of coil misalignment tolerances. Results depend on the following quantities: Input beam Emittance calculation Channel geometry Channel optics RFs

6. MICE magnetic field MICE proposal lists six different current sets in Table 3.3 Plus, want to simulate no-flip and semi-flip modes G4MICE present capabilities: One default set of currents Cannot do semi-flip (card FieldFlipOption) Cannot change currents coil-by-coil Cannot run MICE Stage III (card NumberOfCoolingCells) Improvements: Have a set of coils and several currents available in data cards Enable current definitions coil-by-coil (Use G4MICE to optimize MICE channel optics)

7. Channel optics Use G4MICE to optimize channel optics Three steps: i) fix currents in FC & CC to achieve desired   in LH ii) fix currents in EC & solenoid to achieve desired B in tracker iii) fix currents in MC to achieve constant   in tracker

8. Geometry & Alignment Obvious stuff: i) Actual shape for Al windows… ii) Local variations in LH density (convection) iii) Stay-clear area Ability to displace every element in the MICE channel i) by fixed amount ii) random displacements

9. RFs Data card for static electric field Data card for on-crest & off-crest  -shaped cavities RF phase: i) leading particle method ii) define phase RF-by-RF B  field produced by RFs

10. G4MICE output Currently we have: i) x,y,z,p x, p y, p z,t at fixed z (MC & Rec.) ii) two z-locations (one in each tracker) Add: i) particle coordinates and momenta at fixed time (time is obtained from RF phase) ii) B-field and E-field iii) vector potential A Insert: i) virtual planes, at any z along the channel, user’s choice ii) z-reference plane in upstream and downstream tracker