The NPCT works on the principle of the zero-flux DC current transformer (DCCT). The DC component of the current flowing through the toroid sensor is detected by a magnetic modulator also called fluxgate or second harmonic detector.

The AC component is detected by a AC Hereward transformer. The two circuits are cascaded in a common feedback loop to generate a magnetic flux which always cancel the primary current flux. The NPCT output is the voltage developed by the feedback current passing through a precision resistor.

Used world-wide on all high-energy particle accelerator to observe very short beam pulses. Exceptional bandwidth and sensitivity are achieved by using amorphous cobalt-based alloy cores specially annealed in a magnetic field to obtain very high permeability and low loss at frequencies to 2 GHz.

FCT can be embedded inside a conflat flange fo direct mounting on the beam pipe.

The ACCT is an evolution of the active transformer first proposed by Hereward in 1960. Compared to the Hereward transformer, the ACCT presents much lower noise, a DC offset of the output reduced to a very small value and excellent long-term stability.

The sensor is built with a single winding, which requires only one wire pair between sensor and electronics; this allows much better EMI rejection when long cables are used. The electronics circuit is multistage, implementing the best low-noise operational amplifier available for this application.

The ICT integrates the signal with a time constant of 1 to 20 nanoseconds, depending on the model. Eddy current losses are negligible and the instrument is a very linear integrator for the very high frequency spectrum typical of a bunched beam signal.

ICT can be embedded inside a conflat flange for direct mounting on the beam pipe.

ICTs are designed for use with Bergoz BCM-IHR-E for signal processing.

The Bergoz Multiplexed Beam Position Monitor (MX-BPM) is an electronics module with superior performance in a small volume. It is a non-intercepting system that has been optimized for use in electron and positron Storage Rings.

LR-BPM Overview

The Bergoz Log-Ratio Beam Position Monitor (LR-BPM) is an electronics module designed for fast processing of beam position signals. To achieve this, the signals are parallel processed in a single pass position measurement. It is a non-intercepting system that is suitable for use in most Linacs, transfer lines, first turns, boosters and fast-cycling synchrotrons.

X and Y outputs are strong analog ±2V signals. S-band / L-band BPM is compatible with Bergoz’ multiplexed BPM and Log-ratio BPMs. They can be plugged into the same chassis.

Precise phase matching of input signals is not required.

One Front-end Filter / Amplifier is required for every BPM pickup electrode. It is tuned to the beam RF or harmonic. It is powered from the S–BPM module via the coaxial cable linking them together. It must be installed close to the BPM pickup block, e.g. 1 meter.

Based on a prototype developed by S. Srinivasan and P.A. Duperrex at PSI, the CR-BCM is a re-entrant cavity resonator used as a beam current monitor. The CR-BCM operates at the fundamental mode of resonance, i.e. transverse magnetic mode tuned to a given harmonic of the beam repetition rate.

The fundamental mode of resonance is proportional to the beam current or to the bunch charge of single beam pulses. The re-entrant cavity resonator provides a position- and beam-size-independent response. Calibration check is possible without dismounting the cavity from the beam line.

CRCDS, A TURN-KEY SOLUTION:

CRCDS stands for Cavity Resonator Current Detection System.

To form a turn-key solution for low current measurement, the CR-BCM can be associated with: