Cern Accelerator School, “Magnets”

CERN Accelerator School, “MAGNETS”

Hall Devices:
Physic & Application to Field Measurements

Stéphane Sanfilippo
Paul Scherrer Institut • 5232 Villigen PSI
Large Research FacilitiesStephane.sanfilippo@psi.ch

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Stéphane Sanfilippo, “Hall Devices”, CAS Magnets, 16-25 June 2009
Hotel Novotel Brugge Centrum, Belgium, 16-25 June 2009

Scope (and limitations) of the course
Answers tothe questions:
Hall effect : what is it ?   V
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Hall devices: basic parameters, practical aspects,  type of Hall probes
Multi axis Hall sensors : status and future challengesMagnetic field measurements with Hall probes: advantages and limitations.
Applications for field measurements in accelerator magnets:  
(examples of measurements at CERN and at the Paul Scherrer Institute) 

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QP+QC> Qi*
* T. Friedman, “the World is flat” (2006)

Not in that course :
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The technology of fabrication like CMOS and (sub) micrometer Hall devices
Magneticmeasurements in inhomogeneous magnetic field
Hall measurements in a fast AC magnetic field
High frequency effects
The Hall device as meansfor characterizing the semiconductors (see Popovic-2004)
Hall effectin sensing applications (see Ramdsen-2006)
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Stéphane Sanfilippo, “Hall Devices”, CAS Magnets, 16-25 June 2009

Outline
1. Hall sensors : Overview of the basic properties
– Hall effect :physical effect
– Some basic properties:
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sensitivity &Offset
Noise, Temperature sensitivity , linearity
Calibration
Zoology of Hall probes

2. Three axis Hall magnetic devices.
– Threeaxis sensors
– The new generation : Magnetometers with IC Hall sensors
– Future challenges

Summary :  Advantages and limitations in magnetic field measurements
3. Application in magnetic fieldmeasurements in beam line magnets
– Ex 1 :Measurements of conventional magnets at the Paul Scherrer Institute
– Ex 2: Sextupole measurements in CERN LHC dipoles
– Ex 3 : Field measurements in...