solid magnet options (and unstudied calorimeter thoughts) paul e. reimer 28 january 2011 physics...
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SoLID Magnet Options (and unstudied calorimeter thoughts)
Paul E. Reimer28 January 2011Physics DivisionArgonne National Laboratory
Paul E. Reimer, SoLID Collaboration Mtg, Magnets Options
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Magnets under consideration or “The usual suspects”
Babar
CLEO
ZEUS
CDF
28 January 2011
Paul E. Reimer, SoLID Collaboration Mtg, Magnets Options
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BaBar
28 January 2011
Superconducting coil
Flux Return
Paul E. Reimer, SoLID Collaboration Mtg, Magnets Options
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BaBar
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Original SoLID MC used BaBar Magnet Baffles are designed assuming BaBar field Probably not available
– Will likely go to Italy
Paul E. Reimer, SoLID Collaboration Mtg, Magnets Options
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CLEO
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ZEUS Magnet
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F. Corriveau, NIM A326 (1993) 470-76
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ZEUS Magnet
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Superconducting coil
Flux Return
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ZEUS Magnet
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CDF magnet
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F. Abe, NIM A271 (1998) 387-403.
Flux Return
Superconducting coil
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CDF
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CDF Magnet has a slightly longer bore than BaBar (move target downstream in magnet)
Flux return not applicable to SoLID Presently available after Tevatron run ends in October
– There are some proposals at Fermilab which are considering using this magnet of the CLEO Magnet
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Magnet Comparison
BaBar CLEO ZEUS CDF
Cryostat Inner Radius 150 cm 150 cm 86 cm 150 cm
Length 345 cm 350cm 245cm 500 cm
Central Field 1.49T 1.5T 1.8T 1.47TFlux Return Iron Yes Yes No No
Cool Icon Yes Yes Yes No
Variation in Current density with z?
Yes ??Varying current
density 25% more current
at endsNo
Available Probably Not?? ?? Probably Probably
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Calorimeter Thoughts
Paul E. Reimer28 January 2011Physics DivisionArgonne National Laboratory
Paul E. Reimer, SoLID Collaboration Mtg, Magnets Options
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Calorimeter in Solenoid Flux Return How to get the light from
the calorimeter to a photosensitive detector?– APD’s– Light Guides out of field
region– Use flux return for
calorimeter
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PMT
in >
10 G
Calo
rimet
er
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Calorimeter in Solenoid Flux ReturnOpen Questions: What does magnetic field do the shower?
– My guess is that charged particles in the EM shower will curl up causing the shower to become shorter and wider
How does magnetic field affect resolution in Energy and in space? Is this a strong function of field strength or direction?
What resolution do we need? [Pb:SciFi at ~1:1 gives 4.5%/sqrt(E)]
Is Iron dense enough? How does the fiber affect the Magnetic flux return?
– My guess is that we use and “effective” μ which is about half that of Fe.
Require detailed MC; Have contacted D. Hertzog about simulations.
How do we cost this?– D Hertzog—driving cost is amount of fiber—Fe less dense than
Pb thus need more fiber.
28 January 2011
PMT
in >
10 G
Calo
rimet
er