Koch, Hans-Christian Bison, Georg Grujić, Zoran D. Heil, Werner Kasprzak, Malgorzata Knowles, Paul E. Kraft, Andreas Pazgalev, Anatoly Schnabel, Allard Voigt, Jens Weis, Antoine 2015-08-21 We report on the design and performance of a highly sensitive combined ³He/Cs magnetometer for the absolute measurement of magnetic fields. The magnetometer relies on the magnetometric detection of the free spin precession of nuclear spin polarized ³He gas by optically pumped cesium magnetometers. We plan to deploy this type of combined magnetometer in an experiment searching for a permanent electric dipole moment of ultracold neutrons at the Paul-Scherrer Institute (Switzerland). A prototype magnetometer was built at the University of Fribourg (Switzerland) and tested at Physikalisch-Technische Bundesanstalt (Berlin, Germany). We demonstrate that the combined magnetometer allows Cramér-Rao-limited field determinations with recording times in the range of, measurements above being limited by the stability of the applied magnetic field. With a recording time we were able to perform an absolute measurement of a magnetic field of ≈ with a standard uncertainty of, corresponding to Δ<em>B</em>/<em>B</em> < 6 ×10⁻⁸. application/pdf https://folia.unifr.ch/global/documents/304507 https://folia.unifr.ch/documents/304507/files/wei_dpa.pdf eng info:eu-repo/semantics/altIdentifier/doi/10.1140/epjd/e2015-60018-7 info:eu-repo/semantics/openAccess License undefined The European Physical Journal D. - 2015, vol. 69, no. 8, p. 1–12 info:eu-repo/classification/udc/53 Design and performance of an absolute 3He/Cs magnetometer http://purl.org/coar/resource_type/c_6501