University of Sannio · MULTI-COIL SOLENOIDS (2/2) When dealing with multi-coil solenoids, each...

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Luca De Vito University of Sannio MONITORING THE MAGNETIC AXIS MISALIGNMENT IN PARTICLE ACCELERATOR SOLENOIDS

Transcript of University of Sannio · MULTI-COIL SOLENOIDS (2/2) When dealing with multi-coil solenoids, each...

Page 1: University of Sannio · MULTI-COIL SOLENOIDS (2/2) When dealing with multi-coil solenoids, each coil may be affected by its peculiar misalignment. Hence, these misalignments have

Luca De Vito

University of Sannio

MONITORING THE MAGNETIC AXIS

MISALIGNMENT IN PARTICLE

ACCELERATOR SOLENOIDS

Page 2: University of Sannio · MULTI-COIL SOLENOIDS (2/2) When dealing with multi-coil solenoids, each coil may be affected by its peculiar misalignment. Hence, these misalignments have

PROLOGUE

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EXTREME LIGHT INFRASTRUCTURE

Extreme Light Infrastructure (ELI) is a new Research Infrastructure of pan-European

interest and part of the European ESFRI Roadmap.

LUCA DE VITO - MONITORING THE MAGNETIC AXIS MISALIGNMENT IN PARTICLE ACCELERATOR SOLENOIDS

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ELI – NUCLEAR PHYSICS

The ELI Nuclear Physics (ELI-NP) facility

focuses on laser-based nuclear physics.

It will host two machines:

a very high intensity laser, where beams

from two 10 PW lasers are coherently

added to get intensities of the order of

1023 - 1024 W/cm2

a very intense, brilliant gamma beam, which

is obtained by incoherent Compton back

scattering of a laser light off a brilliant

electron beam from a conventional linear

accelerator.

LUCA DE VITO - MONITORING THE MAGNETIC AXIS MISALIGNMENT IN PARTICLE ACCELERATOR SOLENOIDS

Applications include nuclear physics experiments to characterize laser – target

interaction, photonuclear reactions, and exotic nuclear physics and astrophysics.

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ELI-NP SOLENOIDS

M1: photogun and electron beam extraction components (solenoid A)

M2: the first S–band accelerating structure and the solenoid B surrounding the S–band structure;

M3: the second S–band accelerating structure

LUCA DE VITO - MONITORING THE MAGNETIC AXIS MISALIGNMENT IN PARTICLE ACCELERATOR SOLENOIDS

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SOLENOIDS FOR BEAM FOCUSING

Solenoids are used for beam focusing.

They behave similarly to converging

glass lenses in optical microscopes.

In order to guarantee an accurate

focusing, the magnetic axis of the

magnet should be obtained with high

precision.

LUCA DE VITO - MONITORING THE MAGNETIC AXIS MISALIGNMENT IN PARTICLE ACCELERATOR SOLENOIDS

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MAGNETIC AXIS MONITORING

When a magnet is in operation, its coils are constantly subject to an

electrodynamic strain. The main reason resides in deformations caused by

thermal effects, despite a cooling system is usually installed. This could result in a

significant misalignment of the magnetic axis from the geometric axis.

The thermal effects are especially present at the magnet start-up, but the

misalignment can drift also during machine runnings, because of the heat

generated by particle beams.

LUCA DE VITO - MONITORING THE MAGNETIC AXIS MISALIGNMENT IN PARTICLE ACCELERATOR SOLENOIDS

An in-operation monitoring of the misalignment is needed

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MULTI-COIL SOLENOIDS

LUCA DE VITO - MONITORING THE MAGNETIC AXIS MISALIGNMENT IN PARTICLE ACCELERATOR SOLENOIDS

ELI-NP Solenoid B

Multi-coil solenoids with coaxial coils were studied for producing a uniform

magnetic field, or particular field configurations, e.g., a near-linear gradient axial

magnetic field.

The use of multi-coil solenoids as focusing structures is of great interest.

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MULTI-COIL SOLENOIDS (2/2)

When dealing with multi-coil solenoids, each coil may be affected by its peculiar

misalignment.

Hence, these misalignments have to be monitored when a strict constraint on

the coils alignment is required, thus allowing to adjust the coils position to

achieve/recover the solenoid design parameters.

In ELI-NP solenoids this can be done with adjustable screws to translate and/or

rotate a single coil, even during its operation, with a precision of tens of

micrometers.

LUCA DE VITO - MONITORING THE MAGNETIC AXIS MISALIGNMENT IN PARTICLE ACCELERATOR SOLENOIDS

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THE CHALLENGE

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ELI-NP MAGNETIC AXIS

MONITORING SPECIFICATIONS

Multi coil solenoid are made by a magnetic yoke that can be imagined as a

cylinder 3 m long with a diameter of 60-80 cm and 12 or more coils grouped in

three or more sets, individually powered and installed inside the yoke.

The challenge is to put the resulting magnetic axis inside an ideal cylinder with

radius ±5 microns, have the capability to check the magnetic axis precision and if

necessary adjust each coil position to achieve/recover the design parameters.

Very hard specs:

we need to measure field difference with very high accuracy

field difference in solenoids is very small

LUCA DE VITO - MONITORING THE MAGNETIC AXIS MISALIGNMENT IN PARTICLE ACCELERATOR SOLENOIDS

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WHAT SHOULD WE

DO AT THIS STAGE?

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… STUDYING

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…BUT ALSO MEETING EXPERIENCED

PEOPLE

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METHODS FOR THE MAGNETIC AXIS

MEASUREMENT

Current method for magnetic axis determination:

LUCA DE VITO - MONITORING THE MAGNETIC AXIS MISALIGNMENT IN PARTICLE ACCELERATOR SOLENOIDS

Stretched wire Vibrating wireHall probe mapper

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HALL PROBE MAPPER

LUCA DE VITO - MONITORING THE MAGNETIC AXIS MISALIGNMENT IN PARTICLE ACCELERATOR SOLENOIDS

K. H. Park, Y. K. Jung, D.E. Kim, H.G. Lee, S.J. Park, C.W. Chung, B.K. Kang, “Field Mapping System for Solenoid

Magnet”, AIP Conference Proceedings, vol. 879, no. 1, pp. 260–263, 2007.

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STRETCHED WIRE

LUCA DE VITO - MONITORING THE MAGNETIC AXIS MISALIGNMENT IN PARTICLE ACCELERATOR SOLENOIDS

J. Di Marco, H. Glass, M. J. Lamm, P. Schlabach, C. Sylvester, J.C. Tornpkins, “Field alignment of quadrupole

magnets for the LHC interaction regions”, IEEE Transactions on Applied Superconductivity, 2000

z1

z2

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VIBRATING WIRE (1/2)

LUCA DE VITO - MONITORING THE MAGNETIC AXIS MISALIGNMENT IN PARTICLE ACCELERATOR SOLENOIDS

Feeding a conducting wire by a sinusoidal current

Magnetic field longitudinal components

Wire oscillation amplitude

Lorentz force

P. Arpaia, C. Petrone, S. Russenschuck, L. Walckiers, “Measuring field multipoles in accelerator magnets with

small-apertures by an oscillating wire moved on a circular trajectory”, Journal of Instrumentation, 2012

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VIBRATING WIRE (2/2)

LUCA DE VITO - MONITORING THE MAGNETIC AXIS MISALIGNMENT IN PARTICLE ACCELERATOR SOLENOIDS

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APERTURE NOT ACCESSIBLE!

Methods actually used for magnet

alignment cannot ne used for in-

operation monitoring.

When in operation, most part of the

solenoid aperture (in particular near

the magnetic axis) is obstructed by

the beam pipe and other equipment.

LUCA DE VITO - MONITORING THE MAGNETIC AXIS MISALIGNMENT IN PARTICLE ACCELERATOR SOLENOIDS

Page 21: University of Sannio · MULTI-COIL SOLENOIDS (2/2) When dealing with multi-coil solenoids, each coil may be affected by its peculiar misalignment. Hence, these misalignments have

BRAIN STORMING (1/3)

Idea 1: To use multiple (3 or 4) vibrating wires.

LUCA DE VITO - MONITORING THE MAGNETIC AXIS MISALIGNMENT IN PARTICLE ACCELERATOR SOLENOIDS

PRO: Sensitivity (Significant vibrations also with low field)

CONS: Hard to obtain several wires with identical mechanical behavior.

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BRAIN STORMING (2/3)

PRO: Easy to build, high accuracy.

CONS: Require field gradient. Static coils can be only in the case of pulsed magnets (NOT the case of ELI-NP!). Not enough space for rotating/translating coils.

LUCA DE VITO - MONITORING THE MAGNETIC AXIS MISALIGNMENT IN PARTICLE ACCELERATOR SOLENOIDS

Idea 2: To use coils.

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BRAIN STORMING (3/3)

Idea 3: To use several Hall transducers

(thanks to Carlo Petrone for the discussion!)

LUCA DE VITO - MONITORING THE MAGNETIC AXIS MISALIGNMENT IN PARTICLE ACCELERATOR SOLENOIDS

PROS: Measuring directly the magnetic field, small, no motion.

CONS: Lower accuracy, possibly damaged by radiation (monitoring during

working).

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RADIATION RESISTANCE FOR ELI-NP

LUCA DE VITO - MONITORING THE MAGNETIC AXIS MISALIGNMENT IN PARTICLE ACCELERATOR SOLENOIDS

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WE KNOW NOW ENOUGH

TO START WORKING

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LET’S GO WITH HALL TRANSDUCERS! (1/2)

LUCA DE VITO - MONITORING THE MAGNETIC AXIS MISALIGNMENT IN PARTICLE ACCELERATOR SOLENOIDS

4 Hall transducers on two planes

perpendicular to the mechanical

axis;

Due to the axisymmetry of the

field, in the aligned case, the Hall

transducers would measure the

same field magnitude.

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LET’S GO WITH HALL TRANSDUCERS! (2/2)

LUCA DE VITO - MONITORING THE MAGNETIC AXIS MISALIGNMENT IN PARTICLE ACCELERATOR SOLENOIDS

If misaligned, the Hall

transducers will not measure the

same magnitude.

The method aims to derive the

equation of the misaligned axis

from the Hall transducer

measurements.

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METHOD DEFINITION (1/4)

Description of the magnetic axis:

LUCA DE VITO - MONITORING THE MAGNETIC AXIS MISALIGNMENT IN PARTICLE ACCELERATOR SOLENOIDS

2 1' ' 'P t O t O O

'

'

O x

O y

x x v t

y y v t

z t d

2 1

2 1

' '

' '

x O O

y O O

v x x

v y y

Assumption of no longitudinal shift:

0'O

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METHOD DEFINITION (2/4)

Under the assumption of a small misalignment:

0 0

0 0

, ,

' , ' , ' '

h h

hk hk h hk hk h

R z R z

B BB r z B R z r R z z

r z

' ' 0, , ,O O x yx y v v R

Magnetic axis

Transducer

positionMisaligned

transducer

position

11H 11'HField

magnitude

Radial position

of the tranducer

LUCA DE VITO - MONITORING THE MAGNETIC AXIS MISALIGNMENT IN PARTICLE ACCELERATOR SOLENOIDS

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METHOD DEFINITION (3/4)

LUCA DE VITO - MONITORING THE MAGNETIC AXIS MISALIGNMENT IN PARTICLE ACCELERATOR SOLENOIDS

2 22

11 1 0 1 1 1 0 1' I I I Ir x R y z z R y

1111 1

1'

2Iz z t d

11 11

11 11

11 11

'

'

I O I x

I O I y

I I

x x t v

y y t v

z t d

11 11 11 11' '2

1I x H O y H O Ht v x x v y y d z

d

I11 belongs to the

magnetic axis

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METHOD DEFINITION (4/4)

Repeating for all probes…

LUCA DE VITO - MONITORING THE MAGNETIC AXIS MISALIGNMENT IN PARTICLE ACCELERATOR SOLENOIDS

0 0

0 0

0 0

0

013 11 '

, /2 , /2

014 12 '

, /2 , /2

023 21 '

, /2 , /2

024 22 '

, /2

12 2

2

12 2

2

12 2

2

12 2

2

O y y

R d R d

O x x

R d R d

O y y

R d R d

O x

R d

RB BB H B H y v v

r d z

RB BB H B H x v v

r d z

RB BB H B H y v v

r d z

RBB H B H x v

r d

0 , /2

x

R d

Bv

z

We need:

Measured field magnitude

values (from triaxial Hall

transducers)

Derivatives of the field

magnitude in the aligned

case (from solenoid mapping

or FEM)

P. Arpaia, B. Celano, L. De Vito, A. Esposito, N. Moccaldi, and A. Parrella, “Monitoring the magnetic

axis misalignment in axially-symmetric magnets,” in Proc. of 2018 Int. Instrum. and Meas. Tech. Conf.,

2018, pp. 1726–1731.

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SOLENOID ANALYTICAL MODEL

LUCA DE VITO - MONITORING THE MAGNETIC AXIS MISALIGNMENT IN PARTICLE ACCELERATOR SOLENOIDS

N. Derby, S. Olbert, “Cylindrical magnets and ideal solenoids”, American Journal of Physics, vol.

78, 2010

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UNIAXIAL TRANSDUCERS VS.

TRIAXIAL TRANSDUCERS

In order to evaluate the magnetic field magnitude we need 3D Hall transducers.

However, 1D Hall transducers show a better accuracy than the 3D ones

Can we modify the method to work with 1D sensors?

LUCA DE VITO - MONITORING THE MAGNETIC AXIS MISALIGNMENT IN PARTICLE ACCELERATOR SOLENOIDS

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USING UNIAXIAL PROBES (1/7)

LUCA DE VITO - MONITORING THE MAGNETIC AXIS MISALIGNMENT IN PARTICLE ACCELERATOR SOLENOIDS

0 0

0 0

, ,

' , ' , ' '

h h

hk hk h hk hk h

R z R z

r z R z r R z zr z

B BB B

Expansion of

the B vector

sinm mr mz r zB B B B B

2 211 13

1 112 14

sin sin

sin sin

v v

d d

v v

d d

0 0

0 0

0 0

, ,

0 0

, ,

' , ' , ' '

' , ' , ' '

h h

h h

r rr hk hk r h hk hk h

R z R z

z zz hk hk z h hk hk h

R z R z

B BB r z B R z r R z z

r z

B BB r z B R z r R z z

r z

Uniaxial probe

measurement

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USING UNIAXIAL PROBES (2/7)

LUCA DE VITO - MONITORING THE MAGNETIC AXIS MISALIGNMENT IN PARTICLE ACCELERATOR SOLENOIDS

Page 36: University of Sannio · MULTI-COIL SOLENOIDS (2/2) When dealing with multi-coil solenoids, each coil may be affected by its peculiar misalignment. Hence, these misalignments have

EXPLOITING FIELD SYMMETRIES

IN THE ALIGNED CASE

LUCA DE VITO - MONITORING THE MAGNETIC AXIS MISALIGNMENT IN PARTICLE ACCELERATOR SOLENOIDS

Page 37: University of Sannio · MULTI-COIL SOLENOIDS (2/2) When dealing with multi-coil solenoids, each coil may be affected by its peculiar misalignment. Hence, these misalignments have

USING UNIAXIAL PROBES (3/7)

LUCA DE VITO - MONITORING THE MAGNETIC AXIS MISALIGNMENT IN PARTICLE ACCELERATOR SOLENOIDS

Page 38: University of Sannio · MULTI-COIL SOLENOIDS (2/2) When dealing with multi-coil solenoids, each coil may be affected by its peculiar misalignment. Hence, these misalignments have

USING UNIAXIAL PROBES (4/7)

LUCA DE VITO - MONITORING THE MAGNETIC AXIS MISALIGNMENT IN PARTICLE ACCELERATOR SOLENOIDS

Transducers placed along the radial direction:

P. Arpaia, B. Celano, L. De Vito, A. Esposito, A. Parrella, and A. Vannozzi, “Measuring the

magnetic axis alignment during solenoids working,” Nature Scientific Reports, no. 8,

2018.

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USING UNIAXIAL PROBES (5/7)

LUCA DE VITO - MONITORING THE MAGNETIC AXIS MISALIGNMENT IN PARTICLE ACCELERATOR SOLENOIDS

Transducers placed along the radial direction:

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USING UNIAXIAL PROBES (6/7)

LUCA DE VITO - MONITORING THE MAGNETIC AXIS MISALIGNMENT IN PARTICLE ACCELERATOR SOLENOIDS

Transducers placed along the axial direction:

P. Arpaia, B. Celano, L. De Vito, A. Esposito, A. Parrella, and A. Vannozzi, “Measuring the

magnetic axis alignment during solenoids working,” Nature Scientific Reports, no. 8,

2018.

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USING UNIAXIAL PROBES (7/7)

LUCA DE VITO - MONITORING THE MAGNETIC AXIS MISALIGNMENT IN PARTICLE ACCELERATOR SOLENOIDS

Transducers placed along the axial direction:

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FEM EVALUATION

LUCA DE VITO - MONITORING THE MAGNETIC AXIS MISALIGNMENT IN PARTICLE ACCELERATOR SOLENOIDS

We would like to evaluate the derivates and the field in the aligned case by FEM

and not only by the analytical model.

The FeM of the ELI-NP SolenoidB was evaluated (multicoil)

The result of the FEM wscompared with the experimentaldata from the magnetcharacterization (by the manufacturer)

The actual FEM used wasobtained then by simulating a single active coil.

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METHOD CONFIGURATION

LUCA DE VITO - MONITORING THE MAGNETIC AXIS MISALIGNMENT IN PARTICLE ACCELERATOR SOLENOIDS

Where to place the Hall probes? Positions minimizing uncertainty

Considered uncertainty sources:

Measurement uncertainty of the Hall transducers (uB)

Uncertainty related to the transducers placing (ug)

Uncertainty of the derivatives of Br (u∂)

Uncertainty of the Bz0 value (uf)

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UNCERTAINTY EVALUATION (1/3)

LUCA DE VITO - MONITORING THE MAGNETIC AXIS MISALIGNMENT IN PARTICLE ACCELERATOR SOLENOIDS

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UNCERTAINTY EVALUATION (2/3)

Considering the order of magnitude of the uncertainties:

uB ≈ 10-4 T typical uncertainty of uniaxial Hall transducers

ug ≈ 10-5 m placement by laser tracker

u∂ ≈ 10-2 T/m, uf ≈ 10-3 T, field model accuracy 1%

In the case of the ELI-NP solenoid, only uB and u∂ give significant contribution:

LUCA DE VITO - MONITORING THE MAGNETIC AXIS MISALIGNMENT IN PARTICLE ACCELERATOR SOLENOIDS

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UNCERTAINTY EVALUATION (3/3)

LUCA DE VITO - MONITORING THE MAGNETIC AXIS MISALIGNMENT IN PARTICLE ACCELERATOR SOLENOIDS

Minima are located for R0/R close to 1 and d ≈ 0.9L

Analytical model FEM (one coil)

Uncertainty is slightly more than 50 μm

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3 TRANSDUCERS PER SIDE (1/3)

In some cases, only 3 positions per side are accessible for probe positioning.

LUCA DE VITO - MONITORING THE MAGNETIC AXIS MISALIGNMENT IN PARTICLE ACCELERATOR SOLENOIDS

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3 TRANSDUCERS PER SIDE (2/3)

LUCA DE VITO - MONITORING THE MAGNETIC AXIS MISALIGNMENT IN PARTICLE ACCELERATOR SOLENOIDS

Transducers placed along the radial direction:

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3 TRANSDUCERS PER SIDE (3/3)

LUCA DE VITO - MONITORING THE MAGNETIC AXIS MISALIGNMENT IN PARTICLE ACCELERATOR SOLENOIDS

Page 50: University of Sannio · MULTI-COIL SOLENOIDS (2/2) When dealing with multi-coil solenoids, each coil may be affected by its peculiar misalignment. Hence, these misalignments have

UNCERTAINTY FOR 3 TRANSDUCERS

LUCA DE VITO - MONITORING THE MAGNETIC AXIS MISALIGNMENT IN PARTICLE ACCELERATOR SOLENOIDS

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UNCERTAINTY FOR 3 TRANSDUCERS

LUCA DE VITO - MONITORING THE MAGNETIC AXIS MISALIGNMENT IN PARTICLE ACCELERATOR SOLENOIDS

Analytical model FEM

Minima are again located for R0/R close to 1 and d ≈ 0.9L

Uncertainty of the vertical coordinate is doubled to about 100 μm

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WHAT ABOUT MULTI-COIL

SOLENOIDS?

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MULTI-COIL SOLENOIDS

For a single cylindrical coil, assuming that the magnetic field is axially symmetric, the

magnetic axis is a straight line and coincides with the symmetry axis of the magnetic

field.

Even assuming the magnetic field of each coil as axially symmetric, the actual

misalignments of such fields make the overall magnetic field not axially symmetric.

We approximate approximated it with a polygonal chain, composed by as many

segments as the number of the coils, where each segment is part of the magnetic axis

of the corresponding coil.

LUCA DE VITO - MONITORING THE MAGNETIC AXIS MISALIGNMENT IN PARTICLE ACCELERATOR SOLENOIDS

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EXTENSION TO MULTI-COIL SOLENOIDS (1/4)

LUCA DE VITO - MONITORING THE MAGNETIC AXIS MISALIGNMENT IN PARTICLE ACCELERATOR SOLENOIDS

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LUCA DE VITO - MONITORING THE MAGNETIC AXIS MISALIGNMENT IN PARTICLE ACCELERATOR SOLENOIDS

EXTENSION TO MULTI-COIL SOLENOIDS (2/4)

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EXTENSION TO MULTI-COIL SOLENOIDS (3/4)

LUCA DE VITO - MONITORING THE MAGNETIC AXIS MISALIGNMENT IN PARTICLE ACCELERATOR SOLENOIDS

P. Arpaia, L. De Vito, A. Esposito, A. Parrella, and A. Vannozzi, “On-field monitoring of the

magnetic axis misalignment in multi-coils solenoids,” Journal of Instrumentation, vol. 13,

2018.

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EXTENSION TO MULTI-COIL SOLENOIDS (4/4)

LUCA DE VITO - MONITORING THE MAGNETIC AXIS MISALIGNMENT IN PARTICLE ACCELERATOR SOLENOIDS

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MAGNETIC FIELD SIMULATION (1/2)

Differences are due to the magnetic shield that in solenoids is often employed to limit

fringe flux, and to reduce the number of ampere-turns for a given focal length.

LUCA DE VITO - MONITORING THE MAGNETIC AXIS MISALIGNMENT IN PARTICLE ACCELERATOR SOLENOIDS

Analytical model

(overposition of the single coil fields) FEM

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MAGNETIC FIELD SIMULATION (2/2)

LUCA DE VITO - MONITORING THE MAGNETIC AXIS MISALIGNMENT IN PARTICLE ACCELERATOR SOLENOIDS

Analytical model

Radial

Longitudinal

FEM without shield

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UNCERTAINTY EVALUATION (1/2)

LUCA DE VITO - MONITORING THE MAGNETIC AXIS MISALIGNMENT IN PARTICLE ACCELERATOR SOLENOIDS

A closed form of the uncertainty is difficult to obtain in this case.

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UNCERTAINTY EVALUATION (2/2)

LUCA DE VITO - MONITORING THE MAGNETIC AXIS MISALIGNMENT IN PARTICLE ACCELERATOR SOLENOIDS

The optimal placing of the N planes couples is approximatively the same for all the N coils.

It corresponds to R0 equal about to the 90% of the aperture, and d equal to about 75% of

the coil length L

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STILL TO DO…

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PLANNED EXPERIMENTAL EVALUATION

To carry experimental tests:

LUCA DE VITO - MONITORING THE MAGNETIC AXIS MISALIGNMENT IN PARTICLE ACCELERATOR SOLENOIDS

@ CERN

on LINAC4 Low Energy Beam Transport

(LEBT) (single coil) Solenoid

@ INFN / LNF

on SPARC focusing solenoid (multi-

coil, similar to the ELI-NP one)

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CONCLUSION

I presented a problem of designing a monitoring method for the magnetic axis

misalignment in solenoids.

Measurement specifications were very challenging and current method for

magnetic axis determination were not suitable due to the inaccessibility of the

magnet aperture.

We designed a new method based on several Hall transducers placed on two

planes orthogonal to the nominal axis of the solenoid (of each coil in the multi-

coil case).

We carried out an uncertainly analysis of the method.

We are now going to realize the experimental evaluation of the method.

LUCA DE VITO - MONITORING THE MAGNETIC AXIS MISALIGNMENT IN PARTICLE ACCELERATOR SOLENOIDS

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PROJECT TEAM

Pasquale Arpaia

University of Naples

Federico II

Luca De Vito

University of Sannio

Alessandro Parrella

University of Lisbon

and CERN

Antonio Esposito,

University of Naples

Federico II

Alessandro Vannozzi

INFN / LNFNicola Moccaldi

University of Naples

Federico II

Biase Celano

University of Naples

Federico II

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BUT ALSO THANKS TO…

Carlo Petrone, CERN

Stephan Russenschuck, CERN

Sandro Tomassini, INFN

Oscar Frascione, INFN

LUCA DE VITO - MONITORING THE MAGNETIC AXIS MISALIGNMENT IN PARTICLE ACCELERATOR SOLENOIDS

Page 67: University of Sannio · MULTI-COIL SOLENOIDS (2/2) When dealing with multi-coil solenoids, each coil may be affected by its peculiar misalignment. Hence, these misalignments have

Luca De VitoLaboratorio di Elaborazione dei Segnali e

delle Informazioni di Misura

Dipartimento di Ingegneria

Università degli Studi del Sannio

[email protected]