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LHCb Dipol Magnet


Magnetic Parameters


Bending power

B dl = 4 Tm   (10 m track length)

Non-uniformity of B dl

5% in acceptance

(hor.: 300 mrad, vert.: 250 mrad)

Excitation current

NI = 2 x 1.3 MA

Electric power dissipation

Pe =  4.2 MW

Stored magnetic energy

Wm  32 MJ


L 2 H

Coil and Current


Coil structure (two coils)

15 mono-layer pancakes per coil

Total number of turns

N = 2 x 225

Conductor material

Aluminium Al-99.7

Conductor cross-section

50 mm x 50 mm

Cooling water channel

= 24 mm

Conductor length

Lc  290 m per pancake

Current in conductor

I 5.8 kA

Current density

s 2.9 A/mm2

Total resistance

R = 125 mW @ 20 C

Total voltage drop (two coils)

U 730 V



Cooling requirements

all pancakes in parallel

Total water flow

f 125 m3/h

Pressure drop of cooling water

Dp 10 bar @ DT = 30 C



Steel quality of yoke

EN S235JR, (old norms: Fe360B, St37-2)

Outer yoke dimensions

hor x vert x beam:  11m x 8 m x 2.6 m

Useful wedged aperture

hor:   2.6 m ==> 4.2 m

(upstream ==> downstream)

vert:  2.2 m ==> 3.5 m

Total magnet extension in beam direct.

Lm  5 m

Weight of yoke

My  1450 ton

Weight of coils

Mc  2 x 25 ton




Installation of LHCb Dipole Yoke, lower part.


LHCb coil, turning lower one by 180













LHCb Dipol Magnet installation completed!



    o (ai + outline version)
    o (eps)

Front page:
    o eps
    o ps
    o gif
    o jpg

Some pictures



This page last edited by RL on June 06, 2012. It was accessed Hit Counter times since March 18, 1998.