Download - Field studies for 2 Tesla data
Field studies for 2 Tesla data
Magnetic field meeting, CERN Oct 19, 2006
V. KarimäkiHelsinki Institute of Physics
Outline
• study of Mapper alignment • simple alignment correction• comparison with Tosca• summary
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Mapper arms and probes tilt effects
Tilt of arms from the plane normal to B:
• causes Br and Bphi coupling to Bz• since Bz is large ans Br and Bphi are small, even small tilt causes large relative effect to Br/Bphi• the effect is sinusoidial as a function arms rotation
Tilt of probes with respect to the arm:
• causes a constant coupling to Bz (independent of phi)
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Correction formulas
Br -> Br + [(i +
j sin(-
j)]Bz
Bphi -> Bphi + [(m +
n sin(-
n)]Bz
- is arm turning angle- 's are probe dependent- 's and 's are arm dependent
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Br vs phi at z=0No alignment correction Mapper alignment correction
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Bphi vs phi at z=0No alignment correction Mapper alignment correction
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Bz and Br vs z, r=0.092 m
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Bz and Br vs z, r=0.500 m
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Bz and Br vs z, r=0.908 m
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Bz and Br vs z, r=1.316 m
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Bz and Br vs z, r=1.724 m
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Summary
• 2 Tesla field studied• comparison with Tosca• study of Mapper alignment correction in the plane z=0• of the order 1 mrad corrections• fairly good agreement with Tosca• Bz scale difference about 1.0075
• maps with higher current next
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