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The Centre for Dating and Diagnostics was established in 2001 at the University of Salento with the aim of becoming a National Centre for radiocarbon dating by AMS. After more than fifteen years of operation this goal has been fully achieved with thousands of dated samples for researches spanning from Archaeological, Earth and Forensics sciences to industrial and environmental applications. Furthermore, in the frame of different large scale National projects, the experimental potential of the facility has been substantially improved through the installation of new beam lines and experimental set-ups.

The Capitoline she wolf is a Bronze statue located at the “Capitoline Museums” in Rome, Italy. The extraordinary cultural and symbolic importance of the statue is mainly related to the myth of the Capitoline she wolf and to the legendary origin of the city of Rome. Though traditionally considered an Etruscan bronze, recently a much more recent age was suggested on the base of consideration related to the used casting technique. In this paper we present the results of an AMS radiocarbon dating campaign carried out on the organic residues found in the casting cores recovered from the inner part of the statue. The obtained results firmly anchor the statue to the XI-XII centuries CE, in the Middle Ages.

The determination of the age of elephant ivory is a crucial aspect in the fight against illegal ivory trade which is still a relevant problem having triggered the decline of elephant populations due to poaching in different areas of the globe. Indeed, the absolute dating of the ivory allows, in forensics practice, to establish whether a determined sample or object was obtained and imported illegally, violating the international trade ban. In this frame the use radiocarbon dating has surely a great potential and is widely used. In this paper we review the potential of the method in this field, highlighting its advantages and drawbacks. In particular we show, through the discussion of real cases, how it is possible to improve the achievable chronological resolution by refining the obtained ages trough the proper use of available information and considerations.

A new sputtering ion source has been installed at CEDAD (Centre for Dating and Diagnostics) at the University of Salento in Lecce, Italy. The installation of the new ion source, capable of accepting both solid and gas samples, required significant modifications of the existing low energy injector of the accelerator mass spectrometry (AMS) system. The new ion source is connected, through an in-house designed gas handling interface, to an elemental analyzer which combusts the samples to carbon dioxide and splits the gas into an IRMS system and also to the gas feed line of the ion source. This arrangement allows the simultaneous measurement of C, N content (in the EA), carbon and nitrogen stable isotopic ratios by IRMS and radiocarbon (14C) by AMS on samples with masses in the microgram range. The results of different tests performed to find optimal operational conditions and to improve the system performances are presented. The performances of the system as a function of the diameter of the glass capillary used to feed the source and the pressure of the gas mixture in the syringe are also presented. The achievable precision and blank levels are discussed together with the results obtained in environmental studies.

In this paper, we present the results of the accelerator mass spectrometry radiocarbon (AMS14C) dating campaign performed on samples selected from different levels in Grotta Romanelli (Castro, Italy). Grotta Romanelli is one of the key sites for the chronology of Middle Pleistocene–Holocene in Mediterranean region. After the first excavation campaigns carried out in the first decades of the 1900s, the cave has been systematically re-excavated only since 2015. During the last excavation campaigns different faunal remains were selected and submitted for 14C dating in order to confirm the chronology of the cave with a higher resolution. Isotopic ratio mass spectrometry (IRMS) measurements were also carried out on faunal remains.

A new type of “speleothem” was recently found and described in submarine caves along the Southern coast of the Adriatic Sea in Italy. Previous studies demonstrated the fully biogenic and submarine origin of these structures which appeared to be formed by calcareous tubules of worms, embedded in a much finer texture matrix. AMS radiocarbon dating analyses allowed the determination of the age of these structures and to study the temporal evolution of their growth rate. In this paper, we report new dates obtained on the matrix around the already dated core tubules. Compositional analyses demonstrated that the matrix is mainly formed by calcium carbonate and AMS radiocarbon age measurements performed at CEDAD suggest its biogenic origin. Absolute ages on the matrix are statistically consistent internally and with the calcareous tubules. The obtained results are highly complementary to other studies being performed in order to identify the biological processes governing the formation and growth of these structures.

We present the general design features and preliminary performances of a new system for the simultaneous AMS-14C and IRMS δ13C and δ15N measurements on samples with masses in the μg range. The system consists of an elemental analyzer (EA), a gas splitting unit (GSU), a IRMS system, a gas handling interface (GHI) and a sputtering ion source capable of accepting gaseous samples. A detailed description of the system and of the control software supporting unattended operation are presented together with the first performance tests carried out by analyzing samples with masses ranging from 8 μgC to 2.4 mgC. The performances of the system were tested in term of stability of the ion beam extracted from the ion source, precision and accuracy of the results by comparing the measured isotopic ratios with those expected for reference materials.

A new experimental set-up dedicated to the simultaneous measurements of stable carbon and nitrogen isotopic ratios by IRMS (Isotope Ratio Mass Spectrometry) and 14C by AMS (Accelerator Mass Spectrometry) has been installed at CEDAD (Centre for Dating and Diagnostics)-University of Salento. The new set-up is formed by different functional blocks: an elemental analyzer, an IRMS spectrometer, a gas handling unit and a new hybrid sputtering ion source, connected to the AMS system. The general features of the new system are presented as well as the technical solutions adopted for its integration with the existing AMS system. Different tests were performed by analyzing samples of known isotopic composition and of different masses in order to define optimal operating conditions. In particular it is shown how radiocarbon measurements with precision of 0.6–0.7% and 1% are possible with the new system on samples of mass of the order of ∼20 μg and ∼10 μg, respectively. Background levels of the order of 10−14 (14C/12C) have been also demonstrated. The new system has then significantly extended the experimental potential of the Centre in several research fields where the possibility to date very low mass samples is either a crucial advantage or mandatory such as in environmental sciences and cultural heritage dating.

A dedicated sample processing line for the extraction of dissolved inorganic carbon (DIC) from seawater and groundwater for accelerator mass spectrometry (AMS) radiocarbon analysis has been developed at CEDAD, the Center for Dating and Diagnostic of the University of Salento, Lecce, Italy. The features of the new system are presented together with tests carried out to determine its functionality and background levels. The first results obtained at CEDAD for analyzing seawater samples taken from the Northern Adriatic compare well with results obtained for the same samples analyzed at ETH Zurich. DOI: 10.2458/azu_js_rc.55.16268

The ancient Egyptian mummy discovered in the wooden coffin of Ankhpakhered, priest of the god Min, has been studied at CEDAD (Centre for Dating and Diagnostics) at the University of Salento, Italy. The CT scan, performed by the multidisciplinary team of the Mummy Project of Milan, highlighted unusual features of the mummy, suggesting a reuse of the sarcophagus. Furthermore, specimens were taken via endoscopy for accelerator mass spectrometry (AMS) radiocarbon dating and Fourier transform infrared (FTIR) analyses, which have been carried out at CEDAD. DOI: 10.2458/azu_js_rc.55.16404

Archaeological surface surveys carried out near Salve in southern Italy led to the identification of about 90 stone mounds spread over an area of about 100 ha. Systematic archaeological investigations allowed to identify the mounds as funeral structures with some having megalithic features. In the necropolis, both the inhumation and cremation rituals are evident, in some cases within the same mound. This article presents the results of an accelerator mass spectrometry (AMS) radiocarbon dating campaign carried out on different kinds of samples recovered from several structures: unburned and cremated bones, charcoals, and organic residues extracted from pottery sherds. The results allowed to assess the chronology of the site and to shed new light on the different funeral practices in Copper Age southern Italy. DOI: 10.2458/56.17887

Accelerator mass spectrometry (AMS) radiocarbon analyses were performed on biobased unsaturated polyester resins in order to assess the potential of the method for the determination of the bio-fraction. Different resins were synthesized in the laboratory with different proportions of raw materials of biogenic origin, and analyzed both in the liquid and in the solid form. As a preliminary step of the study, both the biobased and the fossil-derived raw materials were analyzed in order to determine their 14C content. A comparison of the obtained results with the expected ones allowed us to investigate the potential of the 14C method in this field as well as to address some still open issues such as the levels of uncertainty and accuracy as related to the calculation procedures, the correction for isotopic fractionation, and the effect of the presence of volatile components in the analyzed materials.