AGS warm snake status and field mapping

AGS warm snake status and field mapping Junpei Takano

The warm snake is under measurement in bldg.902.

29.Jan.2004 updated

Temperature rise

Thermo graphic data @ 2700Amp.

37 ℃

20 ℃

It is no problem within this temperature.

Temperature rise

Average temperature rise = 10.5 ℃@ total water flow rate = 185 gal/min

3:31:29 PM 4:21:29 PM 5:11:28 PM

14

16

18

20

22

24

26

28

30

32

34

36

38

Tem

pera

ture

(C

)

Time

Wtr. Out Wtr. In

Calculated data:temperature rise = 14.8 ℃@ total water flow rate = 162 gal/min

This calculated value includesome safety margin.

Magnetic field on the z-axis

-150 -100 -50 0 50 100 150-20000

-15000

-10000

-5000

0

5000

10000

15000

20000

B [

gau

ss]

Z [cm]

Bx By |B|

This graph is the simulated data by using OPERA_3D.

L1 = 39 [cm], L2 = 132 [cm]P1 = 90 [cm/rev] , P2 = 184 [cm/rev]

- 1.5 - 1.0 - 0.5 0.0 0.5 1.0 1.5

- 1.5

- 1.0

- 0.5

0.0

0.5

1.0

1.5

Y [

cm]

X [cm]

- 150 - 100 - 50 0 50 100 150

- 1.5

- 1.0

- 0.5

0.0

0.5

1.0

1.5

X, Y

[cm

]

Z [cm]

X Y

L2, P2 L1, P1L1, P1

Simulated beam trajectory

deflection angle = 0

offset = 0

offset = 0

these parameters were optimized

This beam trajectory is perfect !

Beam trajectory

-1.5 -1.0 -0.5 0.0 0.5 1.0 1.5

-1.5

-1.0

-0.5

0.0

0.5

1.0

1.5

y [c

m]

x [cm]

2GeV 5GeV 10GeV 15GeV 20GeV 25GeV

-150 -100 -50 0 50 100 150

-1.5

-1.0

-0.5

0.0

0.5

1.0

1.5

y [c

m]

z [cm]

2GeV 5GeV 10GeV 15GeV 20GeV 25GeV

-150 -100 -50 0 50 100 150

-1.5

-1.0

-0.5

0.0

0.5

1.0

1.5

x [c

m]

z [cm]

2GeV 5GeV 10GeV 15GeV 20GeV 25GeV

~ depending on the energy ~

-80 -60 -40 -20 0 20 40 60 800.0

0.5

1.0

1.5

2.0

2.5

3.0

3.5

4.0Fi

eld

Ang

le [

rad/

pi]

z [inch]

Measured Actual model (OPERA) Perfect model (OPERA)

Measured magnetic field

This graph shows the Field Angle.It is almost fine.

Error study

However these beam trajectories are the result of the ideal simulated model. The actual magnet has some errors.The main errors which should be considered are:

B-H curve of the steelPacking factor of the laminationsDimensional errors because of the lamination pressingDeformation of the yokeCoil position error

→ The model which is completely like the actual magnet must be simulated.

The operation current is one of the method for correcting the beam trajectory.

- 2.0 - 1.5 - 1.0 - 0.5 0.0 0.5 1.0 1.5 2.0

- 2.0

- 1.5

- 1.0

- 0.5

0.0

0.5

1.0

1.5

2.0

y [c

m]

x [cm]

80% 85% 90% 95% 100% 105% 110%

- 150 - 100 - 50 0 50 100 150

- 2.0

- 1.5

- 1.0

- 0.5

0.0

0.5

1.0

1.5

2.0

x, y

[cm

]

z[cm]

80%_x 80%_y 85%_x 85%_y 90%_x 90%_y 95%_x 95%_y 100%_x 100%_y 105%_x 105%_y 110%_x 110%_y

Current = 80% to 110%

Beam trajectory~ depending on the current ~

-2.0 -1.5 -1.0 -0.5 0.0 0.5 1.0 1.5

-1.5

-1.0

-0.5

0.0

0.5

1.0

1.5

2.0y

[cm

]

x [cm]

shim x1 shim x2 shim x3 shim x4 shim x5

The Beam output position will change on this way,if the shims are put on the pole piece.

Beam trajectory

Measured magnetic field

-60 -40 -20 0 20 40 60

0.0

0.2

0.4

0.6

0.8

1.0

1.2

1.4

1.6B

[T

esla

]

z [inch]

2668A (100%) 2537A (95%) 2404A (90%)

These plots are the measured data without shims.

Measured magnetic field

-60 -40 -20 0 20 40 60

0.0

0.2

0.4

0.6

0.8

1.0

1.2

1.4

1.6B

[T

esla

]

z [inch]

2668A (100%) 2537A (95%) 2404A (90%) perfect_model

The plot of the perfect model is calculated data by using OPERA_3DThe simulated data was analyzed by using virtual harmonic coil on OPERA.

The harmonic coil data shows 97% of the actual magnetic flux because of probe length.In actually the magnetic flux is 1.52T.

Measured magnetic field

-60 -40 -20 0 20 40 60

0.0

0.2

0.4

0.6

0.8

1.0

1.2

1.4

1.6B

[T

esla

]

z [inch]

2668A (100%) 2537A (95%) 2404A (90%) actual_model

The actual model plot is the simulated data which model include some errors.

This is the beam trajectory of the actual model.The output beam has offset and deflection angle.This beam trajectory was optimized by using matrix.

-2.0 -1.5 -1.0 -0.5 0.0 0.5 1.0 1.5

-1.5

-1.0

-0.5

0.0

0.5

1.0

1.5

2.0

y [c

m]

x [cm]

Beam trajectory

-1.5 -1.0 -0.5 0.0 0.5 1.0 1.5

-1.5

-1.0

-0.5

0.0

0.5

1.0

1.5

y [c

m]

x [cm]

Beam trajectoryThe result of the matrix about the current and shims are: current = 94.5% shims = 0.7This trajectory is the output with 95% current and a shim.

Magnetic flux at the center of the magnet is 1.46 Tesla.

Measured magnetic field

-60 -40 -20 0 20 40 60

0.0

0.2

0.4

0.6

0.8

1.0

1.2

1.4

1.6B

[T

esla

]

z [inch]

am_cr95%_shim*1 perfect_model

The optimized simulation data is similar to the plot of the perfect model.Next slide shows zoom up of this plots.

Measured magnetic field

-40 -20 0 20 401.0

1.2

1.4

1.6

1.8

B [

Tes

la]

z [inch]

2537A (95%) perfect_model am_cr95%_shim*1

Measured magnetic field

40

1.2

1.5

B [

Tes

la]

z [inch]

2668A (100%) 100%_3shims 2537A (95%) 95%_3shims 2404A (90%) 90%_3shims

Measurement data with 3 shims

Measured magnetic field

0 20 40

1.0

1.2

1.4

B [

Tes

la]

z [inch]

2537A (95%) 95%_3shims perfect_model

Comparing to the perfect model.The warm snake is under correctable.

Summary

The magnetic flux is more powerful than simulation model at full current.But the beam trajectory is under control with current and shims.Currently the magnet is measured by using integral coil probe.I heard the integral data is good.The data will be coming up soon.And I am analyzing the measured magnetic field.These slides are the latest up date data.I’ll send the newest analyzed data to you.

Thank you so much for taking care for me.

29.Jan.2004 Jun