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In this work the new laboratory LAB CER of LNS/INFN, devoted to analysis of ceramics, is presented. The results of quantitative determination of elements on reference standards are presented and discussed.

The archaeological investigation of the finds within the votive deposit of Alaimo in Lentini (Sicily, Italy) showed the presence of three reference classes of pottery. Nevertheless, some artefacts were difficult to classify both for their stylistic typology and for the colour and consistence of the clay pastes Among these samples, a group of Rhodian-like aryballoi has been evidenced. In order to group the finds and to identify the doubtful artefacts, the content of some trace elements (Rb, Sr, Y, Zr and Nb) has been determined in 28 well preserved samples of different pottery shapes. Measurements have been performed by using a portable non destructive XRF spectrometer at the Archaeological Museum of Lentini. Compositional data of trace elements have been determined by using a new method based on a multilinear regression approach. A best relative fit and a multivariate cluster analysis have been performed; analytical results allowed for the verification of the presence of groups of membership among the analysed objects and the classification of some artefacts of doubtful archaeological categorization.

In the present work the portable PIXE- system realized within a collaboration between the IBAM/CNR, the INFN/LANDIS (Catania, Italy) and the CEA/LIST (Saclay, France) has been used, in combination with the upgraded XRD diffractometer, for non destructive analysis. It is shown that, by combining the two techniques, quantitative analysis is possible in selected cases. Application to Roman frescoes fragments coming from different archaeological sites of Catania (Italy) is presented.

In this work the results of recent measurements performed by the LANDIS laboratory of the LNS/INFN using the XPIXE-alpha system and the BSC-XRF spectrometer at the Archaeological Museum "A. Salinas" in Palermo are presented and discussed. In particular, the XPIXE system was used to analyse the pigments present in a Hellenistic sarcophagus and the BSC-XRF system to characterize the bronze alloys composing two ancient sculptures.

Vengono presentate le tecniche e discussi i risultati di misure effettuate presso il Museo Archeologico Regionale "A. Salinas" di Palermo. Gli interventi riguardano: misure quantitative della lega della scultura bronzea raffigurante un ariete, proveniente dal Castello Maniace di Siracusa, datata intorno alla prima età Imperiale Romana; misure quantitative della lega di una statuetta bronzea di Reshef, rinvenuta al largo di Sciacca, datata intorno al XIII-XI sec a.C.; caratterizzazione dei pigmenti in un sarcofago antropoide in marmo, rinvenuto nella necropoli fenicia in località Pizzo Cannita, datato intorno alla metà del V sec. a.C. La strumentazione, portatile, è consistita nel sistema BSC-XRF (Beam Stability Controlled-XRF) e nel sistema XPIXE ( Misura simultanea PIXE ed XRF) del laboratorio LANDIS del LNS/IBAM . I risultati hanno fornito informazioni sulla omogeneità delle leghe e sulla presenza di precedenti restauri, nonché sulla natura dei pigmenti.

A new version of the portable XRD (X-Ray Diffraction) system of the LANDIS laboratory of Catania is presented. The previous apparatus, a commercial portable diffractometer, was equipped with a new X-ray source realised by using a low-power microfocus tube coupled to a polycapillary semi-lens optics. The new experimental set-up allowed to improve the angular resolution and to increase the intensity of peaks in the diffractograms with respect to those measured with the previous version of the system. Finally, the application of the diffractometer for the non-destructive characterisation of pigments present in some fragments of ancient Roman frescoes is discussed.

It is well known that the content of trace elements present in archaeological obsidians can give information on the provenance. Their quantitative determination can be obtained by using portable XRF spectrometers; however, x-ray tubes largely used as exciting source can be subjected to energy and intensity fluctuations and frequent calibrations of the systems are required in order to obtain quantitative data. In the present work a portable BSC-XRF spectrometer (Beam Stability Controlled XRF) with a beam stability control, is used to determine the content of some trace elements (Rb, Sr, Y, Zr and Nb) characterizing obsidian samples. The control of the stability is not an electronic device operating on the applied high voltage and current but consists on a direct intervention on the beam emitted by the tube used as x-ray source. The concentration of Rb, Sr, Y, Zr and Nb was determined in 57 obsidian artefacts coming form Milena, an important prehistoric site in the internal region of Sicily; quantitative determination was obtained by a method based on a multi-linear regression approach previously developed by the authors and based on a calibration procedure which used 26 petrologic standards. It should be emphasized that in the case of obsidians, a surface XRF analysis gives meaningful quantitative results since they are composed of an homogeneous matrix. Milena artefacts were found on well defined archaeological layers dated back from the Neolithic to the final Copper age; this aspect is of relevant interest because only few data exists on stratigraphic obsidians in Sicily. Analysed artefacts were randomly sampled in order to well represent the populations in the different periods. Results on compositional data of Rb, Sr, Y, Zr and Nb allowed to identify Lipari and Pantelleria islands as the main sources of the Milena obsidians and to evidence how the samples coming from these sources are distributed from Neolithic to the final Copper age.

The main characteristics of the new portable XPIXE-alpha spectrometer are described. The system consists of a 244Cm radioactive source which emits both alpha particles and x-rays. Due to the different behaviour of the ionisation cross section of alpha particles and x-rays this source enables to well excite both light elements and medium ones. A possible application is presented.

E' mostrato come l'uso combinato dei sistemi portatili PIXE-???XRF?ed XRD può fornire informazioni quantitative nello studio di pitture murali ed in particolare di affreschi antichi. Infatti l'analisi elementare qualitativa PIXE consente di individuare gli elementi (Z>10) presenti in superficie e nello stesso tempo di limitare le possibili fasi mineralogiche da prendere in esame. L'analisi quantitativa PIXE, infine, condotta introducendo nel programma di analisi i composti precedentemente individuati mediante XRD, permette una completa caratterizzazione delle superfici in studio. Si discute il caso degli interventi nello studio delle superfici degli affreschi del palazzo di Nestore a Pylos.

Da qualche anno i pigmenti di rivestimento delle ceramiche Robbiane sono stati oggetto di caratterizzazione e di studio da parte dei gruppi di Firenze e di Genova adoperando la tecnica PIXE con acceleratori. In particolare si è cercato di determinare la presenza di arsenico in quanto tale elemento risulta utile alla datazione delle opere essendo presente solo a partire da una certa data in poi. Molte indagini sono state così effettuate, anche nel quadro della collaborazione europea COST G8, su frammenti trasportabili presso i laboratori di analisi. Recentemente presso i LNS a Catania sono state sviluppate tecniche di analisi elementare (PIXE ed XRF) con strumenti portatili. Si è potuto cosi intervenire direttamente sulle opere Robbiane conservate presso il Museo del Bargello e caratterizzare sul posto i pigmenti dei rivestimenti. In una prima campagna di misure effettuate accoppiando le tecniche PIXE ed XRF si è determinata tramite il PIXE la matrice (Na, Mg, Al, Si, K, Ca, Pb) e tramite XRF gli elementi in traccia caratterizzanti (Fe, As, Ni, Co, Cu). I dati ottenuti sono di tipo quantitativo (ovviamente nell'ipotesi che i rivestimenti analizzati siano di composizione omogenea). Si presentano gli strumenti e i risultati ottenuti.

A new portable XRF spectrometer which allows the control of the energy and the intensity stability of the emitted x-ray beam has been designed and realised. The control is obtained by measuring the x-ray fluorescence generated by a Ag/Ba double-thin-target when crossed by the x-ray beam during the measurements. The silver and barium fluorescence K lines are detected by an ancillary Si-PIN detector and analysed by a software developed at the LNS/INFN laboratories. The new portable spectrometer, the beam stability-control method, the test on the system stability as well as some quantitative applications are presented and discussed

The Bibbia Amiatina has been analyzed, using non-destructive techniques. The original goal of these research was to establish the original arrangement of the sheets, numbered I to VIII, present in the first booklet. To this end, the pigments that left impressions (offsets) on adjacent sheets and the offsets themselves, were analyzed with XRF, PIXE-a and Raman. They were then observed under UV light it has been possible to hypothesize an order for the sheets, even if it is impossible to establish whether or not this sequence truly represents the original one, or simply that which the sheets have assumed for most of the document's lifetime. For a complete characterization all pigments were analyzed , allowing to detect the color palette.

After the development of the capillary technique, X-Ray microbeams have been widely used to perform elemental concentration determination on small samples of some hundred microns or less[1]. In several cases they produce results as accurate as more expensive facilities. In this work we describe an X-Ray microbeam spectrometer (400 ?m spot size) installed at the "Laboratori Nazionali del Sud" (CATANIA). Quantitative and qualitative studies on a petrologic sample and on a Russian icon are presented as application of the device.

Vengono presentati i primi risultati delle determinaioni degli elmenti presenti in pigmenti ricoprenti manufatti ceramici antichi. il metodo usato è il PIXE. Le determinazioni vengono effettiate mediante uno spettrometro poratile che fa uso di una sirgente alfa di 210-Po. Vengono presentati: a) i risulati di una campagna di misura in situ volta alla determinazione del Mn in pigemnti neri su ceramica preistorica; b) la messa in evidenza di un faslo "Cratere Attico" atraverso lo studio della vernice nera.

Breakup temperatures in central collisions of 197Au + 197Au at bombarding energies E/A = 50 to 200 MeV were determined with two methods. Isotope temperatures, deduced from double ratios of hydrogen, helium, and lithium isotopic yields, increase monotonically with bombarding energy from 5 MeV to 12 MeV, in qualitative agreement with a scenario of chemical freeze-out after adiabatic expansion. Excited-state temperatures, derived from yield ratios of states in 4He, 5Li, 6Li, and 8Be, are about 5 MeV, independent of the projectile energy, and seem to reflect the internal temperature of fragments at their final separation from the system. PACS numbers: 25.70.Mn, 25.70.Pq, 25.75.-q, Comment: 10 pages, RevTeX with 4 included figures; Also available from http://www-kp3.gsi.de/www/kp3/aladin_publications.html