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We report on the performance of a fine-grained 13-ton compensating lead/scintillating-fiber calorimeter, and in particular on its capability of localizing the particles that produce showers in it. The RMS position resolution was found to be 1 .7 mm for electromagnetic showers and 5.1 mm for hadronic showers at 80 GeV, averaged over a tower with an effective radius of 39 mm. Pion-pion separation through analysis of the energy deposit pattern was achieved in more than 95% of the cases for distances down to 8 cm at 80 GeV. Because of the good lateral position resolution, detailed information on the longitudinal shower development could be obtained, with the help of tracking information, when single particles entered the (longitudinally unsegmented) detector at a small angle with respect to the fiber axis. This information made it possible to eliminate the effects of light attenuation in the fibers on the hadronic energy resolution and allowed e/m separation at the 10-°level.

Micro X-ray fluorescence (micro-XRF) analysis and neutron imaging techniques, namely 2D radiography and 3D tomography, have been applied for the study of four metal axes from the Early/Middle Bronze Age in Western Iberia, a period characterized by a metallurgical change in the use of copper to bronze. Micro-XRF analysis has shown that one of the axes was produced in copper with some arsenic while the other three were produced in a copper-tin alloy (bronze) with variable tin contents and some arsenic and lead. Neutron radiography and tomography were applied to study internal heterogeneities of the axes in a non-invasive way since the specificities of neutron interaction with matter allow a suitable penetration of these relatively thick copper-based objects when compared to the use of a conventional X-ray radiography. Neutron imaging allowed the visualization of internal fissures and pores and the evaluation of their distribution, size and shape. Relevant information for the reconstruction of ancient manufacturing techniques was gathered, revealing that one ax was produced with the mold in an angle of ≈25°, probably to facilitate gas escape during metal pouring. Also, information regarding physical weaknesses of the axes was collected, providing relevant data for their conservation. Novelty statement: The present paper combines the use of micro-XRF and neutron imaging techniques, namely (2D) radiography and (3D) tomography for the study of prehistoric metal axes. The XRF spectra allowed identifying major and minor elements present in the alloys, inferring on the absence of elements that could become radioactive for a long period of time after irradiation with neutrons. The specificities of neutron interaction with matter allowed a suitable penetration of these relatively thick copper-based objects when compared to the use of a conventional X-ray radiography. The combination of these non-destructive techniques allowed the evaluation of the metal composition and the internal structure of the axes. Micro-XRF allowed the distinction among copper and bronze axes, and provided data about the composition of early bronzes for which data is scarce. The neutron imaging study allowed for the first time the visualization of internal heterogeneities in early bronze axes, namely pores and large voids, providing relevant information for the reconstruction of ancient manufacturing techniques and raising pertinent information regarding physical weaknesses of these types of objects.

A digital system to characterize solid state nuclear track detectors(SSNTD) has been developed. It was used in the study of two detectors and its performance evaluated by comparing the obtained results with those determined by using an analog system, already in use for such purpose. The comparison of the results together with the feasibility and rapidness in data acquisition have demonstrated the viability of the digital system to characterize SSNTD.