A wide-line low frequency electron paramagnetic resonance spectrometer

A continuous wave, homodyne, low frequency electron paramagnetic resonance spectrometer is described which can accommodate 15 cm diameter objects. The spectrometer can utilize small volume and surface coil probes operating between 100 and 500 MHz. The magnetic field can be scanned between 0 and 35 mT and is thus suitable for g < 2 spins and wide absorption lines. The spectrometer can record conventional field swept, field cycled, and spatially resolved spectra. Details of the instrument design and representative spectra from six different samples are presented. This design has applications to study objects with cultural heritage significance.