Magnetic field reconstruction using the pulsed wire method: An accuracy analysis

Abstract

Learning how to reconstruct the magnetic field profile from the pulsed wire method (PWM) is of fundamental importance to characterize undulators with limited magnetic gap accessibility. This paper presents a new data processing approach to reconstruct undulator magnetic field profiles from the PWM. We study via numerical simulations the accuracy and precision of the novel approach to recover the local undulator parameter and the root-mean-square (RMS) phase error. Due to the wire parameters uncertainties, the PWM can, in the best case, reach an accuracy of approximately 10−3 to reconstruct the local undulator parameter, and a precision (needed to determine the magnetic field quality) of about 10−5. Furthermore, our results show that the RMS phase error can be determined with a precision better than 0.2°. This contribution opens the possibility to apply the PWM to perform magnetic field reconstruction in small-gap short-period long undulators for advanced light sources.