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The implementation in the RIKEN-RAL negative muons facility of a new muon beamline monitoring and novel digital data acquisition system for gamma and X-ray spectroscopy are presented. This work also shows the high potential of the muonic atoms X-ray spectroscopy technique in non-destructive elemental characterization of archaeological samples.

Debasement of silver Roman coins is a well-known phenomenon and understanding the quality of ancient silver coinages can provide an idea about the underlying fiscal condition of the issuing states. These coins are made from a silver-copper alloy, the surfaces of which were deliberately enhanced at the mints by a process of surface-enrichment to give them the appearance of being made of pure silver. Therefore, any surface analysis would provide a composition of the silver-copper alloy that would not be representative of the original alloy from which the coin blank was made, the result would be too high in silver. However, the bulk of the sample, the interior, should provide a composition that is true to the original alloy. Elemental analysis using negative muons has been used to provide a depth dependent compositional, completely non-destructive analysis of a silver-copper alloy denarius of the empress Julia Domna datable to 211&ndash, 217 CE. The composition of the coin, beyond the surface enrichment layer, is 51 &plusmn, 1.8 % copper and 49 &plusmn, 1.9% silver, taken at a muon depth of 402 &plusmn, 61 &micro, m. The surface enrichment layer is approximately 190 &micro, m thick.

The development of elemental analysis at the ISIS pulsed neutron and muon facility, STFC Rutherford Appleton Laboratory, UK, is described. Presented are recent results from the calibration of the new setup and this shows the technique can be a powerful tool in determining the composition of materials in bulk, not just at the surface. Moreover, this technique is non-destructive and should be sensitive to all elements (perhaps with the exception of H and He).

The idea of the CHNET-TANDEM experiment is to develop and optimize a non-destructive technique, which allows analysis deep inside the sample with a good spatial resolution, using a negative muon beam. By selecting the primary muon energies appropriately, bulk analysis can be performed without destructing the sample. The experimental setup used for this experiment, made by 2 hodoscopes and 5 HpGe, allowed us to collect very interesting preliminary data concerning scan momentum, positioning and centering of the samples by means of two hodoscopes, analysis of standard material targets and elemental characterization of Nuragic “Bronze Age” votive ship fragments.

The main features of the Data AcQuisition systems for the FAMU (on muonic atom physics) and CHNET _ TANDEM (on the development of nondestructive techniques to archaeometry) INFN projects will be described. Both the experiments exploit the RIKEN-RAL Muon Facility beam of ( 20 , 120 ) MeV ∕ c muons and the same experimental setup, which includes a wide range of detectors: HPGe detectors for high resolution spectroscopy ; LaBr 3 scintillators , with both PMT and SiPM readout, for fast and high time resolution spectroscopy; several layers of 32 SiPM readout scintillating fibers for beam monitoring with good spatial and time resolution. The performance of the DAQ in terms of conditioning and processing of such a large number of different detector signals, data storage and analysis and a few examples of the results will be presented.