1. Pulsed Magnetic Measurements. Technical description.
Optical sensor based on Faraday effect:
Polarization of light, passing through a magneto-optical crystal, is rotated by magnetic field;
To enhance resolution/accuracy, polarization plane must be rotated multiple times by 360° (i.e. high Verdet constant) within the intended current range;
Count number of full rotations and angle of partial rotation.
Connected via fibre optics to measurement system  very high isolation voltage.
Initially developed at ETHZ as by-product of a PhD.
Sketch of Faraday effect in a cylindrical magneto-optical crystal
Possible arrangement of the magneto-optical crystal between two conductors of a busbar

2. Pulsed Magnetic Measurements. Overview summary.
Goal
Primary goal: High bandwidth, high accuracy pulsed current and field measurement
Secondary goal: Vacuum compatible and radiation resistant
Timescale to possible deployment
Medium term for prototype CLIC DR IA (~3+ years?)
Medium-long term for meas. current in existing kicker systems (5+ years)
Long term for meas. field in existing kicker systems (vacuum compatible, rad. resist.)
Long term for FCC
Gains w.r.t. present technology
High accuracy current, direct measurement of pulsed field (e.g. Tc of ferrite exceeded?)
Possible deployment scope
Kicker systems in general: initially MKI & MKP-L (current & field)?
Ongoing activity domains - projects and present resource levels
FCC [<0.1 STAFF]
Present status and outlook
Collaboration with ETH Zurich under discussion (PhD student to be at ETHZ) – possible financing from TE & CHART (Swiss Collaboration on Accelerator Research and Technology)
Section Involvement
BTP X EC
EDS
KSC
PPE Xx SE

3. Pulsed Electric Measurements. Technical description.
Resistive dividers (can be capacitively compensated)
e.g. for PFN voltage: generally limited bandwidth
Capacitive dividers for pulse measurement
e.g. kicker magnet input and output
Fibre optic electric field sensor:
Based on electric-optical effect – refractive index varies according to Kerr effect.
Commercial units available (e.g. Agiltron Inc.) – based on probing dual-fibre with a laser (1550nm, 20mW at 100MHz).

4. Pulsed Electric Measurements. Overview summary.
Goal
High bandwidth, high accuracy pulsed voltage and field measurement
Timescale to possible deployment
Medium-long term for meas. current in existing kicker systems (5+ years)
Long term for meas. field in existing kicker systems
Gains w.r.t. present technology
Fibre optic system  low noise
Possible deployment scope
Kicker systems in general
Ongoing activity domains - projects and present resource levels
None
Present status and outlook
Research ongoing, e.g. on optical fibers at Royal Institute of Technology KTH, Sweden.
Section Involvement
BTP X EC XX
EDS
KSC
PPE SE ??