1. 1 26 Nov 2010 SOLID ABSORBERS Solid absorbers will provide first cooling demonstration –This is important for a number of reasons! Can use only solids in Step III.x –In particular LiH If starting with Step IV not so clear –Caution suggests may be better to start with solid rather than LH2 Any conflicts with other planning?? What would we like to do? (As shown at the last VC on 18 Nov 2010)

2. 2 26 Nov 2010 Would like to verify cooling formula Dependence on: Momentum Optics (beta_t) Material (via Xo and dE/dX) And more subtle things such as: Growth of canonical angular momentum....??

3. 3 26 Nov 2010 What variables do we have? 3 Beam momenta 3 Beam emittances –(Actually 16 diffuser settings... if it works...) Flip / Non-flip (solenoid) optics Some ability to tune beta at absorber –It’s a long time since we really looked at this What we can do will depend on performance & margins of magnets as built –Probably more freedom at lower momenta –Assume 2 betas for each momentum in both flip & non-flip = 3 x 3 x 2 x 2 = 36 points (on some graph) for each material –Surely enough –But might take too long to do for (say) 4 or 5 materials

4. 4 26 Nov 2010 How long might such a set of measurements take? Data statistics 50 – 100k muons / point should be ~ enough We have measured 27 tracks / spill / Volt-mSec (M. A.’s talk at NuFact) Don’t know what that means in terms of good muons into MICE for acceptable beam loss Assume 5 useful muons / spill 10k seconds ~ 3 hours for 50K muons Say 4 hours

5. 5 26 Nov 2010 Overheads 1.Change absorber Mechanical tasks –8 days (A.N. at CM28) –May now have come down to 5 days (tbc) 2.Flip / Non-flip Run down magnets, swap cables or links, checks, run up.... Will not be quick; probably needs an expert 3.Change momentum & beta of cooling channel Retune FCs, Match coils and (maybe) Spectrometer Solenoids Need advice from magnet experts but guess will take a few hours. May need expert to do it? 4.Change momentum & emittance of beam Some magnets need retuning at each (p,epsilon) setting And diffuser Should be fairly quick (~ 1 hour??)

6. 6 26 Nov 2010 No large efficiency factors or contingency –but many guesses Overheads seem to dominate May like better to balance overheads & running? Suggests ~3 weeks for a complete set of measurements with one material plus 8 days (~2 weeks) to change an absorber Would also like empty (no absorber) running – so double the time? –but do this only once Would we really want to do this with all materials? –5 materials  ~150 days ~ 1/2 a year Rough estimates of time for one solid absorber – large error bars!

7. 7 26 Nov 2010 To clarify.... Change Absorber ~ 8 days Run in Flip in Mode ~11 days Run in non-Flip Mode ~11 days ~ 30 days total to do Flip & Non-Flip ~ 21 days total to do Flip (or NF) only Data taking & some expert (?) intervention to change S/C magnets interspersed

8. 8 26 Nov 2010 Possible Strategy Make full set of measurements to verify p, beta dependence with one material –LiH is the obvious candidate Make sufficient measurements with 3 or 4 other materials to verify material dependence –Not all the possible optics Flip mode only One beta (canonical 42 cm) All (p,epsilon) –Might be able to do 1 material in ~15 - 16 days total Need to understand that number better!