Error characterization and calibration of real-time magnetic field measurement systems

Development of a Real-Time Magnetic Field Measurement System for Synchrotron Control

“…Then, we quantified the contribution of all system components to the measurement latency, finding that overall, it remains always well below the specified 30 µs tolerance. Therefore, we conclude that the new CERN B-train electronic acquisition system meets all its requirements, as it was also independently verified by running an extensive series of operational tests, as reported in detail in[7].…”

“…We characterized experimentally the DC response of the system first, showing that after calibration, the voltage acquisition error across the ±10 V input range has an arithmetic and an RMS mean of, respectively, Nevertheless, certain improvements still seem necessary to guarantee compliance with upcoming, more challenging use cases. First of all, we are currently working on the algorithm to set optimally the fine offset correction ∆V 2 in (7), including the possibility of increasing the bit depth of the final flux integration stage so as to make the injection of an analogue voltage unnecessary (this would probably require newer, more capable FPGAs). An upgrade to the timing system is being considered to improve the internal LVDS transmission between SPEC modules in the FEC, which is currently a major limitation.…”

“…The Field Marker Trigger Generator module has the goal of detecting the resonance peak in the output V m of an NMR or FMR resonator and to generate a TTL trigger pulse accordingly. The module has a dual-channel design that allows, for example, having a high-field and low-field marker acting at different times on the same integration channel (as in ELENA [7]) or two markers acting in parallel on two separate integration channels (as in the PS). We recall that the B-train crate has a number of connectors sufficient to handle up to four field marker signals, corresponding to up to two SPEC/FMC cards operating in parallel in the same FEC.…”

“…FIRESTORM has been designed to cope with the High-Luminosity Large Hadron Collider upgrade, which will require higher beam intensity and improved beam control throughout the injector chain [6]. After an extensive, successful test phase [7], deployment is currently ongoing across the CERN complex with the new systems expected to be fully operational for the upcoming LHC physics run. In Sections 2 and 3 of this work, we discuss the broad measurement principle and overall architecture of the system.…”

“…The existing resonators cover a measurement range from 36 mT to 110 mT. Overall, the effective reproducibility of the marked field can be as low as 1 µT under optimal conditions [7].…”