Novel optical interferometry of synchrotron radiation for absolute electron beam energy measurements

P. Klag, P. Achenbach, M. Biroth, T. Gogami, P. Herrmann, M. Kaneta, Y. Konishi, W. Lauth, S. Nagao, S. N. Nakamura, J. Pochodzalla, J. Roser, Y. Toyama

Research output: Contribution to journalArticlepeer-review

2 Citations (Scopus)


A novel interferometric method is presented for the measurement of the absolute energy of electron beams. In the year 2016, a pioneering experiment was performed using a 195 MeV beam of the Mainz Microtron (MAMI). The experimental setup consisted of two collinear magnetic undulators as sources of coherent optical synchrotron light and a high-resolving grating monochromator. Beam energy measurements required the variation of the relative undulator distance in the decimeter range and the analysis of the intensity oscillation length in the interference spectrum. A statistical precision of 1 keV was achieved in 1 h of data taking, while systematic uncertainties of 700 keV were present in the experiment. These developments aim for a relative precision of 10−5 in the absolute momentum calibrations of spectrometers and high-precision hypernuclear experiments. Other electron accelerators with beam energies in this regime such as the Mainz Energy Recovering Superconducting Accelerator (MESA) might benefit from this new method.

Original languageEnglish
Pages (from-to)147-156
Number of pages10
JournalNuclear Instruments and Methods in Physics Research, Section A: Accelerators, Spectrometers, Detectors and Associated Equipment
Publication statusPublished - 2018 Dec 1


  • Beam energy measurement
  • Electron accelerator
  • Optical interferometry
  • Synchrotron radiation
  • Undulator


Dive into the research topics of 'Novel optical interferometry of synchrotron radiation for absolute electron beam energy measurements'. Together they form a unique fingerprint.

Cite this