The arduous sacred paths in the Upper Garda Bresciano, towards the sanctuary of Iuppiter Aeternus in Villanuova sul Clisi (Valle Sabbia)

Atlante Tematico Di Topografia Antica 35 (2025) 27-38

Authors:

S Solano, A Buonopane, GL Gregori

Abstract:

Recent archaeological research in the Valle Sabbia in the territory of Brescia (BS-Northern Italy) has led to the discovery of a new place of worship from the Roman era, possibly built on an ancient indigenous sanctuary. The Valle Sabbia is one of the alpine valleys of Lombardy, north of Brescia (the Colonia Augusta Civica Brixia). The territory, crossed by the river Chiese, stretches between Lake Idro and Lake Garda, in a favourable geographical position that puts it in direct contact with the plain on one side and the Alps on the other. Since 2000, campaigns of archaeological excavations have led to the discovery of different contexts that can be interpreted as sacred, with frequenting from prehistoric times to Roman times and which have as recurrent characteristic a close relationship with the surrounding landscape, with a clear preference for mountainous and wooded contexts. The most important novelties, concerning the Roman period, emerge in Villanuova sul Clisi, where on a panoramic hill overlooking the entire Valle Sabbia and Garda Lake, various wall structures have emerged that define a complex built on several levels, with a rectangular main room of about 11×4,20 m, made with large structures confining the summit plateau, and other lateral ones. The recovered materials indicate a visitation from the 1st to the 4th century A.D.: in addition to coins, fibulae and ceramics, some miniature metal ex-voto with dedications to Iuppiter Aeternus, various graffiti on plaster and a stone altar also inscribed have been uncovered.

Investigating the impact of intermediate-mode perturbations on diagnosing plasma conditions in DT cryogenic implosions via synthetic x-ray Thomson scattering

Plasma Physics and Controlled Fusion IOP Publishing 67:1 (2024) 015034

Authors:

H Poole, D Cao, R Epstein, I Golovkin, VN Goncharov, SX Hu, M Kasim, SM Vinko, T Walton, SP Regan, G Gregori

Abstract:

The pursuit of inertial confinement fusion ignition target designs requires precise experimental validation of the conditions within imploding capsules, in particular the density and temperature of the compressed shell. Previous work has identified x-ray Thomson scattering (XRTS) as a viable diagnostic tool for inferring the in-flight compressed deuterium-tritium shell conditions during capsule implosions (Poole et al 2022 Phys. Plasmas 29 072703). However, this study focused on one-dimensional simulations, which do not account for the growth of hydrodynamic instabilities. In this work, two-dimensional DRACO simulations incorporating intermediate-mode perturbations up to Legendre mode ℓ=50 were used to generate synthetic XRTS spectra with the SPECT3D code. The analysis employed Markov-Chain Monte Carlo techniques to infer plasma conditions from these spectra. The results demonstrate that the XRTS diagnostic platform can effectively discern the in-flight compressed shell conditions for targets with varying adiabats, even in the presence of intermediate-mode perturbations. This work underscores the potential of XRTS for realistic inertial confinement fusion experiments, providing a robust method for probing the complex dynamics of fusion implosions.

Nonthermal solid-solid phase transition in ferromagnetic iron

Physical Review B - Condensed Matter and Materials Physics American Physical Society 110 (2024) 214434

Authors:

Sam Azadi, Justin Wark, Sam Vinko

Abstract:

We posit the existence of a nonthermal phase transition in iron, driven by a loss of ferromagnetic ordering on ultrafast timescales with increasing electron temperature. The transition corresponds to a solid-solid BCC to FCC phase transformation and takes place at an electron temperature of 0.62 eV while the ion lattice remains near room temperature. The BCC structure initially undergoes phonon softening during the magnetic transformation, followed by a solid-solid phase transition to the FCC structure, and a subsequent hardening of phonon modes. We present a detailed physical picture of the process, supported by finite-temperature density functional theory simulations of the phonon dispersion curves, electronic density of states, and thermodynamic free energy.

Statistical theory of the broadband two-plasmon decay instability

Journal of Plasma Physics Cambridge University Press 90:6 (2024) 905900621

Authors:

Ruskov Rusko, Robert Bingham, Luis Silva, Max Harper, Ramy Aboushelbaya, Jason Myatt, Peter Norreys

Abstract:

There is renewed interest in direct-drive inertial confinement fusion, following the milestone December 2022 3.15 MJ ignition result on the National Ignition Facility. A key obstacle is the control of the two-plasmon decay instability. Here, recent advances in inhomogeneous turbulence theory are applied to the broadband parametric instability problem for the first time. A novel dispersion relation is derived for the two-plasmon decay in a uniform plasma valid under broad-bandwidth laser fields with arbitrary power spectra. The effects of temporal incoherence on the instability are then studied. In the limit of large bandwidth, the well-known scaling relations for the growth rate are recovered, but it is shown that the result is more sensitive to the spectral shape of the laser pulse rather than to its coherence time. The range of wavenumbers of the excited plasma waves is shown to be substantially broadened, suggesting that the absolute instability is favoured in regions further away from the quarter critical density. The intermediate bandwidth regime is explored numerically – the growth rate is reduced to half its monochromatic value for laser intensities of 1015 W/cm2 and relatively modest bandwidths of 5 THz. The instability-quenching properties of a spectrum of discrete lines spread over some bandwidth have also been studied. The reduction in the growth rate is found to be somewhat lower compared to the continuous case but is still significant, despite the fact that, formally, the coherence time of such a laser pulse is infinite.

Dynamical development of strength and stability of asteroid material under 440 GeV proton beam irradiation

(2024)

Authors:

Melanie Bochmann, Karl-Georg Schlesinger, Charles Arrowsmith, Paraskevi Alexaki, Marta Alfonso Poza, Mohamed Ambarki, Emily Andersen, Pablo Bilbao, Robert Bingham, Filipe Cruz, Aboubakr Ebn Rahmoun, Alice Goillot, Jonathan Halliday, Brian Huffman, Eva Kamenicka, Michael Lazzaroni, Eva Los, Jean-Marc Quetsch, Brian Reville, Panagiota Rousiadou, Subir Sarkar, Luis Silva, Pascal Simon, Enrica Soria, Vasiliki Stergiou, Sifei Zhang, Nikolaos Charitonidis, Gianluca Gregori