Multi-Scale Monitoring of Rupestrian Heritage: Methodological Approach and Application to a Case Study

Most of the artistic heritage in the Mediterranean basin is hosted in rupestrian hypogeum whose peculiarity is given by the presence of at least one open side, which makes them particularly sensitive to meteorological conditions. This makes mandatory the monitoring of both indoor and outdoor environmental parameters to analyze the cause–effect relationship between microclimatic inside and outside the hypogeum. The paper proposes a spatial and temporal multi-scale methodological approach applied to a rupestrian church in Matera, which hosts precious wall paintings, particularly vulnerable to the effects of environmental parameters. The approach is based on the analysis of data acquired by three platforms: indoor, close-range outdoor, and outdoor data from a meteorological station and weather forecast from the COSMO 5 model. The method allowed to characterize the relationships between the indoor and outdoor parameters at different spatial and temporal scales. The results showed a significant correlation between the parameters, thus opening new opportunities for the monitoring of the rupestrian heritage based on the use of data systematically available, such as those from meteorological stations and meteorological forecast

Georadar investigations to detect cavities in a historical town damaged by an earthquake of the past

This paper aims to highlight the use of the georadar as a useful prospecting technique to identify the areal density and the geometrical features of the grottoes placed in a historical town characterised by high seismic hazard. <br><br> The town considered here is Rionero in Vulture (Southern Italy) that was hit by several historical earthquakes, among which the 1930 Irpinia earthquake (Me=6.7, Is=VIII MCS). <br><br> For this event a damage map was already available from a previous study (Gizzi and Masini, 2006). This map shows that some sectors of the town suffered higher damage. One factor causing the uneven distribution of the effects is considered to be the presence of grottoes. <br><br> To strengthen this work hypothesis it was necessary to in-depth investigate the subsoil of Rionero in Vulture. Therefore, geophysical data were correlated and integrated with data obtained from field surveys and historical documentary sources. All these investigations allowed to obtain more insights about the influences of the man-made caves on seismic damage

Acceleration with Self-Injection for an All-Optical Radiation Source at LNF

We discuss a new compact gamma-ray source aiming at high spectral density, up to two orders of magnitude higher than currently available bremsstrahlung sources, and conceptually similar to Compton Sources based on conventional linear accelerators. This new source exploits electron bunches from laser-driven electron acceleration in the so-called self-injection scheme and uses a counter-propagating laser pulse to obtain X and gamma-ray emission via Thomson/Compton scattering. The proposed experimental configuration inherently provides a unique test-bed for studies of fundamental open issues of electrodynamics. In view of this, a preliminary discussion of recent results on self-injection with the FLAME laser is also given.Comment: 8 pages, 10 figures, 44 references - Channeling 2012 conferenc

Dynamics of charge-displacement channeling in intense laser-plasma interactions

The dynamics of transient electric fields generated by the interaction of high intensity laser pulses with underdense plasmas has been studied experimentally with the proton projection imaging technique. The formation of a charged channel, the propagation of its front edge and the late electric field evolution have been characterised with high temporal and spatial resolution. Particle-in-cell simulations and an electrostatic, ponderomotive model reproduce the experimental features and trace them back to the ponderomotive expulsion of electrons and the subsequent ion acceleration.Comment: 5 figures, accepted for publication in New Journal of Physic

Data-driven modeling reveals the Western dominance of global public interest in earthquakes

Catastrophic earthquakes stimulate information-seeking behaviors beyond the affected geographical boundaries; however, our understanding of the dynamics of global public interest in earthquakes remains limited. Herein, we harness Big Data to examine the dynamic patterns of global public interest, concerning 17 significant worldwide earthquakes over 2004–2019. We find that the global community shows a higher level of interest when an earthquake occurs in developed countries than in developing countries; however, they lose their interest in the former more rapidly than the latter. Regardless of the affected nation, there is a one- to two-week “golden” time window when attention can be leveraged for fundraising and humanitarian aid. Our findings suggest that European citizens who are highly interested in earthquakes emerge as a potential key community to achieve great inclusiveness in policy interventions to solicit international aid. The findings of this study hint at how Big Data can be utilized to identify “time windows of opportunities” for international humanitarian organizations to efficiently raise donations, charities, and aid resources around the world

Decreasing pH impairs sexual reproduction in a Mediterranean coral transplanted at a CO2 vent

Ocean acidification, due to the increase of carbon dioxide (CO2) concentration in the atmosphere and its absorption by the oceans, affects many aspects of marine calcifying organisms' biology, including reproduction. Most of the available studies on low pH effects on coral reproduction have been conducted on tropical species under controlled conditions, while little information is reported for either tropical or temperate species in the field. This study describes the influence of decreasing pH on sexual reproduction of the temperate non-zooxanthellate colonial scleractinian Astroides calycularis, transplanted in four sites along a natural pH gradient at the underwater volcanic crater of Panarea Island (Tyrrhenian Sea, Italy). The average pH values of each site (range: pHTS 8.07–7.40) match different scenarios of the Intergovernmental Panel on Climate Change (IPCC) for the end of the century. After 3 months under experimental conditions, the reproductive parameters of both oocytes and spermaries (abundance, gonadal index, and diameters) seem to be unaffected by low pH. However, a delay in spermary development in the pre-fertilization period and a persistence of mature oocytes in the fertilization period were observed in the most acidic site. Furthermore, no embryos were found in colonies from the two most acidic sites, suggesting a delay or an interruption of the fertilization process due to acidified conditions. These findings suggest a negative effect of low pH on A. calycularis sexual reproduction. However, long-term experiments, including the synergistic impact of pH and temperature, are needed to predict if this species will be able to adapt to climate change over the next century

Multi-GeV Electron Spectrometer

The advance in laser plasma acceleration techniques pushes the regime of the resulting accelerated particles to higher energies and intensities. In particular the upcoming experiments with the FLAME laser at LNF will enter the GeV regime with almost 1pC of electrons. From the current status of understanding of the acceleration mechanism, relatively large angular and energy spreads are expected. There is therefore the need to develop a device capable to measure the energy of electrons over three orders of magnitude (few MeV to few GeV) under still unknown angular divergences. Within the PlasmonX experiment at LNF a spectrometer is being constructed to perform these measurements. It is made of an electro-magnet and a screen made of scintillating fibers for the measurement of the trajectories of the particles. The large range of operation, the huge number of particles and the need to focus the divergence present unprecedented challenges in the design and construction of such a device. We will present the design considerations for this spectrometer and the first results from a prototype.Comment: 7 pages, 6 figures, submitted to NIM

Evidence of resonant surface wave excitation in the relativistic regime through measurements of proton acceleration from grating targets

The interaction of laser pulses with thin grating targets, having a periodic groove at the irradiated surface, has been experimentally investigated. Ultrahigh contrast ($\sim 10^{12}$) pulses allowed to demonstrate an enhanced laser-target coupling for the first time in the relativistic regime of ultra-high intensity >10^{19} \mbox{W/cm}^{2}. A maximum increase by a factor of 2.5 of the cut-off energy of protons produced by Target Normal Sheath Acceleration has been observed with respect to plane targets, around the incidence angle expected for resonant excitation of surface waves. A significant enhancement is also observed for small angles of incidence, out of resonance.Comment: 5 pages, 5 figures, 2nd version implements final correction

Time evolution of stimulated Raman scattering and two-plasmon decay at laser intensities relevant for shock ignition in a hot plasma

Laser–plasma interaction (LPI) at intensities 1015–1016 W cm2 is dominated by parametric instabilities which can be responsible for a significant amount of non-collisional absorption and generate large fluxes of high-energy nonthermal electrons. Such a regime is of paramount importance for inertial confinement fusion (ICF) and in particular for the shock ignition scheme. In this paper we report on an experiment carried out at the Prague Asterix Laser System (PALS) facility to investigate the extent and time history of stimulated Raman scattering (SRS) and two-plasmon decay (TPD) instabilities, driven by the interaction of an infrared laser pulse at an intensity 1:2 1016 W cm2 with a 100 mm scalelength plasma produced from irradiation of a flat plastic target. The laser pulse duration (300 ps) and the high value of plasma temperature (4 keV) expected from hydrodynamic simulations make these results interesting for a deeper understanding of LPI in shock ignition conditions. Experimental results show that absolute TPD/SRS, driven at a quarter of the critical density, and convective SRS, driven at lower plasma densities, are well separated in time, with absolute instabilities driven at early times of interaction and convective backward SRS emerging at the laser peak and persisting all over the tail of the pulse. Side-scattering SRS, driven at low plasma densities, is also clearly observed. Experimental results are compared to fully kinetic large-scale, two-dimensional simulations. Particle-in-cell results, beyond reproducing the framework delineated by the experimental measurements, reveal the importance of filamentation instability in ruling the onset of SRS and stimulated Brillouin scattering instabilities and confirm the crucial role of collisionless absorption in the LPI energy balance