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Muography (or muon radiography) is a technique that exploits the penetration capability of muons, elementary particles similar to electrons but with a mass about 200 times larger. High energy muons are naturally produced in the interactions of cosmic rays with the Earth atmosphere. The measurement of their absorption in matter allows the imaging of the inner structure of large bodies. The technological developments in the detection of elementary particles have opened the way to its application in various fields, such as archaeology, studies of geological structures, civil engineering and security issues. We have developed a new approach to the three-dimensional muography of underground structures, capable of directly localising hidden cavities and of reconstructing their shape in space. Our measurements at Mt. Echia, the site of the earliest settlement of the city of Naples in the 8th century BC, have led us to the discovery of a hidden underground cavity, whose existence was not evident with the usual two-dimensional muography graphs. We demonstrate here that our original approach definitely enhances muography discovery potential, especially in case of complex underground systems.

Muon radiography is a technique based on the measurement of absorption profiles of muons as they pass through matter. This measurement allows to obtain an image of the inner structure of large volume objects and is suitable to be applied in several fields, such as volcanology, archaeology and civil engeneering. One of the main applications concerns the study of volcanic structures; indeed it is possible to use this technique to measure the mass distribution inside the edifice of a volcano providing useful information to better understand the possible eruption mechanisms. The MURAVES (MUon RAdiography of VESuvius) project aims to the study of the summital cone of Mt. Vesuvius near Naples in Italy, one of the most dangerous active volcanoes in the world. The MURAVES apparatus is a modular, robust muon hodoscope system with a low power consumption, optimized to be used in inhospitable environments like the surroundings of volcanoes. The complete detection system is an array of identical tracking modules, each with an area of 1 m2, based on the use of plasic scintillators. The technologies, the status and the data analysis strategy of the experiment will be presented in this paper.

Cosmic-ray muon radiography (muography), an imaging technique that can provide measurements of rock densities within the top few 100 m of a volcanic cone, has now achieved a spatial resolution of the order of 10 m in optimal detection conditions. Muography provides images of the top region of a volcano edifice with a resolution that is considerably better than that typically achieved with other conventional methods (i.e. gravimetric). We expect such precise measurements, to provide us with information on anomalies in the rock density distribution, which can be affected by dense lava conduits, low-density magma supply paths or the compression with the depth of the overlying soil. The MUon RAdiography of VESuvius (MURAVES) project is now in its final phase of construction and deployment. Up to four muon hodoscopes, each with a surface of roughly 1 m 2 , will be installed on the slope of Vesuvius and take data for at least 12 months. We will use the muographic profiles, combined with data from gravimetric and seismic measurement campaigns, to determine the stratigraphy of the lava plug at the bottom of the Vesuvius crater, in order to infer potential eruption pathways. While the MURAVES project unfolds, others are using emulsion detectors on Stromboli to study the lava conduits at the top of the volcano. These measurements are ongoing: they have completed two measurement campaigns and are now performing the first data analysis. This article is part of the Theo Murphy meeting issue ‘Cosmic-ray muography’.

The low-lying structures of the midshell νg9/2 Ni isotopes 72Ni and 74Ni have been investigated at the RIBF facility in RIKEN within the EURICA collaboration. Previously unobserved low-lying states were accessed for the first time following β decay of the mother nuclei 72Co and 74Co. As a result, we provide a complete picture in terms of the seniority scheme up to the first (8+) levels for both nuclei. The experimental results are compared to shell-model calculations in order to define to what extent the seniority quantum number is preserved in the first neutron g9/2 shell. We find that the disappearance of the seniority isomerism in the (81+) states can be explained by a lowering of the seniority-four (6+) levels as predicted years ago. For 74Ni, the internal de-excitation pattern of the newly observed (62+) state supports a restoration of the normal seniority ordering up to spin J=4. This property, unexplained by the shell-model calculations, is in agreement with a dominance of the single-particle spherical regime near 78Ni. The low-lying structures of the midshell νg9/2 Ni isotopes 72Ni and 74Ni have been investigated at the RIBF facility in RIKEN within the EURICA collaboration. Previously unobserved low-lying states were accessed for the first time following β decay of the mother nuclei 72Co and 74Co. As a result, we provide a complete picture in terms of the seniority scheme up to the first (8+) levels for both nuclei. The experimental results are compared to shell-model calculations in order to define to what extent the seniority quantum number is preserved in the first neutron g9/2 shell. We find that the disappearance of the seniority isomerism in the (81+) states can be explained by a lowering of the seniority-four (6+) levels as predicted years ago. For 74Ni, the internal de-excitation pattern of the newly observed (62+) state supports a restoration of the normal seniority ordering up to spin J=4. This property, unexplained by the shell-model calculations, is in agreement with a dominance of the single-particle spherical regime near 78Ni. ispartof: Physics Letters B vol:781 pages:706-712 status: published

The MURAVES (MUon RAdiography of VESuvius) project is a joint activity participated by INGV, INFN and the Universities of Naples “Federico II” and Florence. The collaboration, following the experience gained within the previous INFN R&D project Mu-Ray, is currently completing the production of a robust four square meter low power consumption detector to be installed on the flank of Mount Vesuvius, an active volcano located on the western coast of Italy. The detector is supposed to collect data for at least one year, thus allowing performing a scan of the structure of the Vesuvius volcanic cone. In this work the status of the project and some parallel activities on muon radiography are presented.

Zakopane Conference on Nuclear Physics - Extremes of the Nuclear Landscape -- AUG 28-SEP 04, 2016 -- Zakopane, POLAND, WOS: 000398717500011, Mirror energy differences (MED) are a direct consequence of isospin symmetry breaking. Moreover, the study of MED has proved to give valuable information of several nuclear structure properties. We present the results of an experiment performed in GANIL to study the MED in mirror nuclei Mg-23-Na-23 up to high spin. The experimental values are compared with state-of-the-art shell model calculations. This permits to enlighten several nuclear structure properties, such as the way in which the nucleons alignment proceeds, the radius variation with J, the role of the spin-orbit interaction and the importance of isospin symmetry breaking terms of nuclear origin.

The Muon Imaging for Mining and Archaeology (MIMA) project aims at the development of a non-invasive technique for imaging dense structures or cavities, hidden in the underground or anyway surrounded by huge volumes of matter, based on Muon Absorption Radiography. Given its natural multidisciplinary, the final purpose is the validation of this methodology for applications in different fields, like Archaeology, Geology, mining, Civil Engineering and Civil Protection, in close cooperation with team in these fields. In this paper we report on the design, construction and performance of a compact and lightweight muon telescope designed mainly for archaeological investigation and geophysical prospections in general. The MIMA detector is also used currently as a test instrument to study different hardware solutions to optimize the global performance in these types of applications., 24 pages, 17 figures

High-spin states in $^{139}\mathrm{Ce}$ have been populated using the $^{130}\mathrm{Te}(^{14}\mathrm{C},5n)$ reaction. The level scheme has been extended to higher spins, including a new band of dipole transitions. The parity of several states has been changed from negative to positive, mainly based on the comparison with the level structure of the core nucleus $^{140}\mathrm{Ce}$ and the results of a realistic shell-model calculation. The dipole band is interpreted as a magnetic rotation band with $\ensuremath{\pi}{h}_{11/2}^{2}\ensuremath{\bigotimes}\ensuremath{\nu}{h}_{11/2}^{\ensuremath{-}1}$ configuration built on small deformation axial shape with $({\ensuremath{\varepsilon}}_{2}=0.12,\ensuremath{\gamma}={0}^{\ensuremath{\circ}})$.

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