Speaker
Description
The Danfysik precision Hall probe measurement bench has previously been used for field mapping of the demanding MAXLab IV combined function dipoles [1]. This measurement bench has recently been upgraded for position accuracies of better than 10 µm for strait on-the-fly measurements over lengths of up to 5m and has been prepared for efficient measurements along curved trajectories. Work is now in progress to upgrade if for precision mapping of long closed H-type of magnets such as the Diamond booster dipoles [2] with a length of up to 1.3 meter. Our design is partially inspired by the field mapper made at ALBA [3] with a probe suspended on a high tension wire supported by a C-type of carriage structure placed on a long support bench. Our concept is based on a dual master/slave carriage system used to suspend a 3m long carbon rod with a Hall probe placed in the middle.
Efficient on-the-fly precision field mapping of electromagnets requires temperature compensated high stability and high accuracy analog Hall probes such as previously demonstrated [1]. For measurements of multipole magnets like quadrupoles a gradient Hall probe with two probes placed in a known distance on a line perpendicular to the probe scan direction is efficient in minimizing the effect of probe position errors on the gradient measurement. We are currently making an upgraded probe with four Hall elements to allow accurate mapping of local field gradients in higher order multipoles like sextupole and octupole magnets.
An efficient and robust software has been developed for the control of the Hall bench which allow easy selection of measurement probes, power supplies and other equipment. This allows fully automate field measurements including power supply control with a high degree of standardization. A similar concept is use for our stretched wire measurement bench.
Test result will be shown to illustrate the performance of both our Hall probe field mapper and stretched wire measurement systems.
[1] F. Bødker et al., IPAC 2013, p. 36.
[2] J. Campmany et al., Phys. Proc. 75, 2015, p. 1222.
[3] I.P.S. Martin et al., IPAC 2021, p. 286.
