m.apolloniomice analysis meeting 23/1/20071 m. apollonio – university of oxford radius of diffuser...
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m.apollonio MICE Analysis meeting 23/1/2007 1
M. Apollonio – University of Oxford
Radius of diffuser and sizes for PID
m.apollonio MICE Analysis meeting 23/1/2007 2
Let’s consider different optics for MICE
Consider the maximum radius a particle can reach in the tracker (TK) = 15 cm the absorber (ABS) = 15 cm the RF windows (RF) = 21.3 cm
It can be shown that ~ <R2>
Propagate the radius throughout MICE according to
These curves represent the ENVELOPE of the beam whichjust touches the TK, the ABS, the RF and the diffuser == muons with a given amplitude ==
MAX size of diffuserMAX radii in the downstream region
00
XX RR
CAVEAT: field in the downstream region is approximate, neglectingthe presence of the shield!!!
m.apollonio MICE Analysis meeting 23/1/2007 3
current diffuser position
ideal minimum RD
m.apollonio MICE Analysis meeting 23/1/2007 4
Wang-200-42
Z-downstream: shield-in shield-out SW
TOF KL
m.apollonio MICE Analysis meeting 23/1/2007 5
current diffuser position
inside TKs inside ABS inside RF
ideal minumum RD
Every in the TKs will traverse both ABS and RF
RD must be as large as possible10 cm is definitely too small !!!
m.apollonio MICE Analysis meeting 23/1/2007 6
Wang 207-200-193 (with energy loss)
R grows linearly far fromthe solenoid (beta ~ z2)
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Wang-240-42
m.apollonio MICE Analysis meeting 23/1/2007 8
Wang-240-42
m.apollonio MICE Analysis meeting 23/1/2007 9
NF-200-42
m.apollonio MICE Analysis meeting 23/1/2007 10
NF-200-42
m.apollonio MICE Analysis meeting 23/1/2007 11
SFOFO-170-15
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SFOFO-170-15
m.apollonio MICE Analysis meeting 23/1/2007 13
SFOFO-140-7
m.apollonio MICE Analysis meeting 23/1/2007 14
SFOFO-140-7
m.apollonio MICE Analysis meeting 23/1/2007 15
Summary of min R – DIFFUSER (cm)
optics min RD (TK) min RD (ABS) min RD (abs)wang 207-200-193-42 16.2 14.8 12.8wang 200-42 16.2 14.6 12.8wang 240-42 15.8 15.5 13.6NF (TRD) 200-42 16.2 14.4 11.9SFOFO 170-15 16.4 23.6 11.6SFOFO 140-7 16.3 34.9 12.8
m.apollonio MICE Analysis meeting 23/1/2007 16
6399.5 6499.5 6574.5 6649.5 6729.5 7429.5 6524.5 6599.5 6689.5
250
250
100 100 50
50
40
40700
Definition of MIN Radius for PIDs and SHIELD holes!!! NOT IN SCALE (but figures should be correct)
TOF
KL SW
max radius
800
m.apollonio MICE Analysis meeting 23/1/2007 17
optics R input hole R output hole R-TOF R-KL R-SWwang 207-200-193-42 246.5 295.5 272.1 324 587wang 200-42 246.5 296.6 272.1 323 587wang 240-42 223.2 262.5 243.3 284.5 507.3NF (TRD) 200-42 240.2 288 271 314.7 576.5SFOFO 170-15 243.3 291.2 268.9 317.9 576.5SFOFO 140-7 247.6 294.5 271 320 567
According to the defs given in previous slides these are the min radii(a) for the shield (to let every pass) and (b) for the PIDs (to accept every )
Within tolerances
1000x1000 mm2
600x600 700x700 mm2
Slightly out ? tolerances
Is it a problem?
m.apollonio MICE Analysis meeting 23/1/2007 18
Wang-200-42
Z-downstream: shield-in shield-out SW
TOF KL
like having a 20 cmshorter SW calorimeter
But only for the outermuons
m.apollonio MICE Analysis meeting 23/1/2007 19
conclusions
the maximum radii for particles traversing MICE are propagated (from the max R in3 different places) through the apparatus (TKs, ABS, RF)
Considering several optics: min Radius (at fixed position z=-6150 mm) for the diffuser is defined: in order to have particles in the TKs it turn out Rd should be as large as possible
(compatible with mechanical contraints) In any case RD=10 cm is too small !
min radii for downstream shield holes are computed uponthe requirement of accepting every from trackersmin radii for PIDs are computed upon the requirement of having the maximal
acceptance within the detector: this condition can be probably relaxed
Real B field in the “shield area” should take into account real map. This is just an approximation whose purpose is giving some initial figures