1June 1 st 2009MICE CM24 - RAL1 Beamline Optics m. apollonio

D1 D2 Q4 Q1 Q2 Q3 Q5Q6Q7Q8Q9 2June 1 st 2009MICE CM24 - RAL2

Q4 Q1 Dipole1 DK solenoid Q2Q3 Dipole2 Q5Q6Q7Q8Q9 beamline breakdown (  )   3June 1 st 2009MICE CM24 - RAL3  x = 2.55 mm  y = 1.4 mm  x’= 0.33 rad  y’= 0.1 rad  x = mm rad  y = mm rad

4 BeamLine Completion: tuning for all ( ,P) Also known as... the MATRIX search for Q4-5-6 & Q7-8-9 currents to match optics at the u.s. face of the diffuser  fine tuning for every chosen  [3,6,10] mm rad (norm.) at every defined P = [140,200,240] (MeV/c)

 5June 1 st 2009MICE CM24 - RAL5 Q4 Q1 Dipole1 DK solenoid Q2Q3 Dipole2 Q5Q6Q7Q8Q9  INPUT: beamline US section >>>>>>>>> GA procedure - Define 6-genes genotypes: Q currents - Express it as a phenotype: the Twiss parameters at some Z’s - Evaluate phenotype’s fitness - Mate genotypes and produce new individuals - Choose the best & repeat for several cycles GA+Turtle Optimiser OUTPUT: Twiss diffuser US face (+TOF1)

6June 1 st 2009MICE CM24 - RAL6

 =78 cm  =132 cm  =0.4 cm  =0.2 cm   7June 1 st 2009MICE CM24 - RAL7

8June 1 st 2009MICE CM24 - RAL8 Pro’s and con’s of the method - running is fast (2.5 h for initial 70K muons after DKsolenoid) - preparing it a bit cumbersome (TTL…) - 3 decks (US / MID / DS) - I think of a change: - generate    (G4BL) and record  after DKsolenoid - use THIS output as input for GA+TTL optimisation NB In principle the GA algorithm should be able to run G4BL directly - It calls a script via a system call - possibility of tuning the solenoid - CAVEAT : a) need to insert the spectrometer solenoid in the simulation (fringe field) b) could take some time to have a working version

9June 1 st 2009MICE CM24 - RAL9 are we ready? STEP I (shutdown 17 Aug/1 Sept) 2Sept – 25 Oct depends on what we want to reach - beam optics for a beam of 214 MeV/c before diffuser IS ready - it can be easily scaled for other momenta - a check of beam size at TOF1/ECAL should be sufficient to assess it - requires more work IF we need tuning (e.g. beta too big and we need to re-define it) STEP II (shutdown 17 Aug/1 Sept) 2Sept – 25 Oct a bit more laborious - as before, optics exists for e=6,10 and P=214 MeV/c - HOWEVER, this has been tuned for a tracker solenoid present (fringe field) - re-defining it could require some work. We should try using it ‘just so’ - also, matrix has to be completed (hasn’t it to?) - this requires values for B at 140/240 [ B(140)=140/200 * B(200), while B(240)=B(200) ]

10June 1 st 2009MICE CM24 - RAL10 are we ready?   XY (a) well defined problem know  in solenoid know  at US-diffuser  -line tuned (  =6,10 mm rad, P=214 MeV/c) (b) NOT well defined problem  in solenoid ?  -line NOT tuned SUGGESTION: use case (a) tuning as case (b) but beam smaller at TOF2/KL due to less drift SUGGESTION: use case (a) tuning STEP II.1 Q7Q8Q9 Q7Q8Q9 Q7Q8Q9 STEP II.0 STEP I

Q4 Q1 Dipole1 DK solenoid Q2Q3 Dipole2 Q5Q6Q7Q8Q9 1) beamline momentum tuning  P  =208 MeV/c P  =444 MeV/c  P  =214 MeV/c fix D1 fix D2 2) beamline quadrupole tuning P  =255 MeV/c 11June 1 st 2009MICE CM24 - RAL11

P TARGET (MeV/c)P (MeV/c) P TARGET (MeV/c)P (MeV/c) 484~250 P TARGET (MeV/c)P (MeV/c) 390~160 12June 1 st 2009MICE CM24 - RAL12 - a level-0 optics for any P can be obtained by momentum rescling - then a Q tuning is required to match the line

recalculated  =6mm rad, P=207 new tuning  =10 mm rad, P=207 investigate case  =3 mm rad P=207 (does not converge) PLAN: fix P=140/240 and cover the remaining empty elements ??? 13June 1 st 2009MICE CM24 - RAL

Optics - TPT/TTL used so far to define the optics - TPT: matrix transport through material - description decks a bit cumbersome - what if we need to re-define? - can we use something more? - flexible - understandable - capable of matching - MADX? OPTIM 14June 1 st 2009MICE CM24 - RAL14

Optics Why emittance grows here? Q1DS  x= mm rad  y= mm rad 15June 1 st 2009MICE CM24 - RAL15 I ‘d like to cross check with Mark’s calculations on the same set of particles

- a central optics exists for (  ) beamline with P  ~200 MeV/c and  =6 mm rad - level-0 optics for P  =140/240 can be generated by momentum rescaling - a fine tuning of Q[4-9] can be done to match the optics to US-diffuser values [STEPII.1] - optics for STEPII.0/STEPI can be the one for STEPII.1 - so far DKsol is kept fixed (not tuned) - could be inserted in tuning if TTL  G4BL (but requires work) - codes other than TPT (MADX) could be used to improve optics US of DKsol (ditto) Summary 16June 1 st 2009MICE CM24 - RAL16