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The resonance structure in neutron induced reaction cross sections can be used to determine the elemental compositions of materials or objects. The occurrence of resonances is the basis of neutron resonance capture analysis (NRCA) and neutron resonance transmission analysis (NRTA). NRCA and NRTA are fully non-destructive methods to determine the bulk elemental composition without the need of any sample preparation and resulting in a negligible residual activity. They have been applied to determine the elemental composition of archaeological objects and to characterize reference materials used for cross section measurements. For imaging applications a position sensitive neutron detector has been developed within the ANCIENT CHARM project. The detector is based on a 10 × 10 array of 6 Li-glass scintillators mounted on a pitch of 2.5 mm, resulting in a 25 × 25 mm 2 active area. The detector has been tested at the time-of-flight facility GELINA and used at the ISIS spallation source to study cultural heritage objects.

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Neutron resonances are the signature signals of a non-destructive elemental and isotopic analysis technique in archaeological sciences. We report on Neutron Resonance Transmission Analysis and its capabilities as a bulk elemental imaging technique to test the homogeneity of samples and to localize elements of interest in archaeological samples and museum objects. A high neutron flux is required for imaging in order to achieve reasonable spatial resolution and to keep measurement times within realistic limits. A modular system for neutron resonance transmission analysis has been designed and installed at the INES beamline of the ISIS spallation neutron source as a part of the ANCIENT CHARM project. The main component is a neutron position sensitive transmission detector which is based on a 10 × 10 array of 6Li-glass crystals mounted on a pitch of 2.5 mm, resulting in a 25 × 25 mm2 active area. Transmission spectra are obtained by a measurement of the flight time of epithermal neutrons passing through an object. The transmission dips observed in a time-of-flight spectrum can be used to identify and quantify specific nuclides. In this paper the technique is described together with the data reduction and analysis procedures. In addition, preliminary results obtained from measurements on cultural heritage samples are discussed

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