Tracker Solenoid Overview

22 October 2005 MICE Meeting at RAL 1

Tracker Solenoid Overview

Michael A. Green

Lawrence Berkeley Laboratory

MICE Collaboration Meeting

22 October 2005


Tracker Module 1

Tracker Module 2

AFC Module 1AFC Module 3

AFC Module 2

RFCC Module 1

RFCC Module 1

MICE Channel with New Tracker

Drawing by S. Q. Yang


The New Tracker Magnet Design

22 October 2005 MICE Meeting at RAL 4Tracker Magnet Cryostat

Iron Shield

Iron Shield Brackets

Cold Mass Support

Coolers

Vent Stack

Lead Neck

Radiation Shield Space

Tracker Magnet Stand

Cooler Neck



Lead Neck

Cold Mass Support

Liquid He Tube

Fill & Vent Neck

Condenser

4 K Cooler

He Gas Tube

Tracker Magnet Cold Mass and Coolers

The 50 K shields are not shown.



• Cold mass and the Superconducting coils

• Cold mass support system that can carry a 50 ton longitudinal force.

• Cooling system based on three 1.5 W coolers.

• Superconductor specification.

• Temperature margin for all magnet coils.

• Magnet power supply system for both tracker magnet modules.

Magnet Components Studied


End Coil 2

Center Coil

Match Coil 1

End Coil 1

Match Coil 2

Coil Cover

Aluminum Mandrel

Liquid Helium Space

490 mm

690 mm

2535 mm

Tracker Magnet Cold Mass Cross-section



50 K intercept

Tracker Magnet Cold Mass Cold Link

Warm Link

300 K End

4 K End

Tracker Magnet Cold Mass Support System



Cooler #1

Cooler #2 Cooler #3

Cooler 1st Stage

Cooler 2nd Stage

Gas Return PipeFlexible 304 SS

Liquid He Supply Pipe Flexible 304 SS

He Condenser

Top Plate

Tracker Magnet Cooling System



Tracker Magnet Parameters

Parameter Match 1 Match 2 End 1 Center End 2Coil length (mm) 198 197 110 1294 110Coil inner radius (mm) 258 258 258 258 258Coil thickness (mm) 46.2 28.6 61.6 22.0 68.2Number of layers 42 26 56 22 62Number of turns per layer 120 119 66 784 66Coil overall current density (A mm –2) 147.6 161.3 136.8 146.9 145.4Coil current I (A) 267.8 271.2 249.5 265.9 265.2Coil self inductance (H) 12.8 5.0 9.6* 41.6* 11.4*Coil Stored Energy at I (MJ) 0.47 0.20 0.30 1.49 0.40

Uniform Field Magnet S

* The uniform field magnet coils in series have a self inductance of 78 H.

Separately Powered

Coil package length = 2530 mm


Tracker Magnet Temperature Margin

1098765432100

50

100

150

200

250

300

350

400

450

500

T = 3.4 KT = 4.2 KT = 5.0 KTracker M1Tracker M2Tracker E1Tracker CTracker E2

Magnetic Induction at the Conductor (T)

Conductor Current (A)

Tracker M1 Margin = 2.0 KTracker M2 Margin = 2.5 KTracker E1 Margin = 1.9 KTracker C Margin = 2.3 KTracker E2 Margin = 1.7 K

Conductor Ic Versus B


Spectrometer Magnet Power Supplyand Connection

Power Supply±10 V, 300 A

Power Supply±10 V, 50 A

PSPSPSPSPSPSPSPower Supply±10 V, 50 A


The Differences between theOld Design and the New Design


Things that are not Changed

• The length of the cryostat from end plate to end plate is unchanged (~2634 mm), but cold mass length is shorter (2535 mm).

• The 400 mm magnet warm bore is unchanged.

• The 250 mm distance from the far end plate to the iron shield is unchanged.

• The longitudinal position of the coil current centers is unchanged.

• The radiation shield position at the AFC end is unchanged.


Increasing the Cryostat Diameterand the New Stand Design

• The outer diameter of the cryostat was increased from 1080 mm to 1407 mm. In addition, there is a new stand, which is conceptually like the RFCC module stand.

• The new stand takes the 50 ton longitudinal force directly to the floor. Because the tracker magnet cryostat is the same diameter as the AFC and RFCC modules, one can carry the magnetic forces to an adjacent module.

• The iron support was changed to fit the new cryostat diameter.


Other Tracker Magnet Changes

• The radial position of the coil current centers has moved inward because all the coils are thinner (despite a 3 mm increase in the inner coil radius).

• Match coil 1 is 4-mm shorter. Match coil 2 is 5-mm shorter. The two end coils are 11-mm shorter.

• The center coil length has been increased from 1260 mm to 1294 mm. As a result, the field uniformity in the tracker has improved.


Other Tracker Changes continued

• The distance from the end AFC coil to the Match Coil 1 has increased by 2 mm. The distance between the current centers is unchanged.

• The distance between end coil 2 and the iron shield has increased 5.5 mm. The distance from the current center of End Coil 2 to the iron shield is unchanged.

• There may yet be small changes (< 5 %) in the turn number in Match Coil 2, End Coil 1 and End Coil 2.


Tracker Magnet Progress and Future Work


Magnet Progress to Date

• Basic module design is almost completed• Coils designed except for possible minor

changes in a couple of coils.• Superconductor specification and start the

bid process.• Cold mass supports are understood.• Design of the cooling system is understood.• Magnet assembly plan has been started.• Magnet quench analysis has been started.• Power supply specification started.


Magnet Tasks Remaining

• Place the order for the superconductor.• Finish the quench calculations.• Prepare a tracker solenoid specification.• Qualify potential magnet vendors.• Finish the magnet assembly plan and write

quality control documents.• Place the order for the tracker solenoids

(probably more than one contract).• Tracker magnet fabrication.


Concluding Comments

• The new tracker magnet will fit with the rest of the tracker module now being designed.

• The tracker magnet design is far enough along to write a performance specification for tracker magnet procurement.

• The superconductor specification has been written and the RFP will go out soon.

• We have identified a number of potential superconductor and magnet vendors.

Tracker Solenoid Overview

Documents

Transcript of Tracker Solenoid Overview