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The advent of pulsed neutron sources makes available high epithermal neutron fluxes (in the energy range between 500 meV and 100 eV). New dedicated instrumentation, such as Resonance Detectors, was developed at ISIS spallation neutron source in the last years to apply the specific properties of this kind of neutron beam to the study of condensed matter. New detection strategies like Filter Difference method and Foil Cycling Technique were also developed in parallel to the detector improvement at the VESUVIO beamline. Recently, epithermal neutron beams were also used at the INES beamline to study elemental and isotopic composition of materials, with special application to cultural heritage studies. In this paper we review a series of epithermal neutron instrumentation developed at ISIS, their evolution over time and main results obtained.

The gamma-ray background spectra of VESUVIO and INES beamlines, at the ISIS spallation neutron source, were measured with an HPGe spectrometer. These measurements are intended to provide information on typical gamma-ray background spectra in spallation neutron source environments, with special regard to beamlines employing gamma-ray sensitive detectors. Sources and creation processes of more than 60 gamma-ray lines in the energy range 80 keV-12 MeV were identified by using specifically developed data analysis software.

A set of seven musical instruments and two instruments cares from the 'Fondo Antico della Biblioteca del Sacro Convento' in Assisi, Italy, were investigated through neutron and X-ray imaging techniques. Historical and scientific interests around ancient musical instruments motivate an intense research effort for their characterization using non-destructive and non-invasive techniques. X-ray and neutron tomography/radiography were applied to the study of composite material samples containing wood, hide and metals. The study was carried out at the NEUTRA beamline, PSI (Paul Scherrer Institute, Switzerland). Results of the measurements provided new information on the composite and multi-scale structure, such as: the internal structure of the samples, position of added materials like metals, wood fiber displays, deformations, presence of adhesives and their spatial distribution and novel insight about construction methods to guide the instruments' restoration process. © 2014 Elsevier B.V. All rights reserved.

Alcuni tratti di affinità legano tra loro i percorsi compositivi di Luzi e di Sereni, che consentono di individuare il prevalere e l'affermarsi delle istanze sereniane, nella elaborazione della dizione poetica del secondo novecento

We investigate the feasibility of using low energy gamma rays from neutron capture to localize slabs inside samples. A new system based on two gamma ray detectors with 2D collimators to be tested at the INES beamline at the pulsed neutron source ISIS (Oxford, UK) is described. The system provides a localization of slabs inside extended samples by using gamma ray self-absorption. Geant4 Monte Carlo simulations of the beamline were carried out to model gamma spectra from test samples.

An archaeological survey method based on neutron gamma-ray logging is described. The method relies on the measurement of capture gamma radiation induced by neutron irradiation from a pulsed generator. This technique provides elemental information on the irradiated zone by spectroscopic analysis of the gamma-ray data. This approach has been studied with Geant4 Monte Carlo simulations. In particular, irradiation volume for a deuterium-deuterium and deuterium-tritium (D-T) neutron generator and sampling volume for the D-T source were estimated. In addition, a neutron log response, which illustrates the capability of the neutron tool to localize artifacts lying beneath the surface, is shown. © 2013 IOP Publishing Ltd.

A partire dal XII sec. si afferma la volontà di legittimare attraverso una normativa la forma vitae di svariate domus religiose femminili, che ottenendo una validazione giuridica non acquisivano, però, un'identità religiosa uniforme. L'A. dimostra che per i secoli presi in considerazione (XII e XIII) fu prima di tutto la Curia papale che si interessò alle comunità femminili per cercare di annetterle a una regola o a instituta canonicali (in questo caso gli instituta più seguiti erano quelli di s. Agostino) o regolari. Così dopo il canone 13 del concilio lateranense IV Ne nimia religionum diversitas vengono presi in considerazione con analisi comparata il cosiddetto Ordine di San Damiano, che non fu una filiazione francescana, e l'istituzione di San Sisto, fondazione papale. La Curia romana pensò ulteriori institutiones dallo stesso nome, che vennero adottate da varie comunità soprattutto tedesche e francesi. Di queste institutiones non è noto quasi niente, mentre si hanno tre versioni della silloge delle costituzioni dei Predicatori adattate ai monasteri femminili: una del 1228-1231 che si rifà alle costituzioni primitive nella redazione precedente a quella di Raimondo de Peñafort, la seconda del 1241 in Mittelhochdeutsch, la terza del 1250, fatta per il monastero francese di Montargis e sotto il controllo di Umberto di Romans. Quest'ultimo poi uniformò i testi normativi dell'Ordine nel 1259. In appendice viene pubblicata una tabella in cui si confontano i dettati di tre testi, litterae papali con le quali si chiedeva ai frati di annettere i monasteri femminili.