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While silicon has been a steadfast semiconductor material for the past 50 years, it is now facing competition from other materials, especially for detector design. In that respect, due to its high resistance to radiation damage, silicon carbide is one of the most promising materials. In this work, we discuss the radiation damage studies of a new, large area, p-n junction silicon carbide device developed by the SiCILIA collaboration. We have studied the general performances of several devices, as a function of fluence, irradiated in different experimental conditions with different beams. A standard p-n junction silicon detector was also irradiated for comparison. The new detectors manifest excellent performance in terms of stability of the main parameters, linearity, defect distribution, charge collection efficiency, energy resolution, leakage current, etc. Experimental results evidence a radiation resistance of SiC devices more than two order of magnitude higher than Si devices. The new construction technology applied to silicon carbide material has made it possible to create very robust devices with excellent performance. These devices will soon be available for all those scientific projects where a high resistance to radiation damage is required.

Purpose: The main purpose of this work is the inter-comparison between different devices devoted to the transversal dose profile recostruction for daily QA tests in proton therapy., Methods: The results obtained with the EBT3 radiochromic films, used as a reference, and other common quality control devices, have been compared with those obtained with a beam profiling system developed at the "Laboratori Nazionali del Sud" of Italian Institute for Nuclear Physics (INFN-LNS, Catania, Italy). It consists of a plastic scintillator screen (thickness 1 mm), mounted perpendicularly to the beam axis and coupled with a highly sensitive CCD detector in a light-tight box., Results and Conclusion: The tests, carried out both at the INFN-LNS and Trento Proton Therapy Center facilities, show, in general, a good agreement between the different detectors. The beam profiling system, in particular, appears to be a promising quality control device for 2-D relative dosimetry, because of its linear response in a dose rate range useful for proton therapy treatments, its high spatial resolution and its short acquisition and processing time., (Copyright © 2020 Associazione Italiana di Fisica Medica. Published by Elsevier Ltd. All rights reserved.)

In equation (1) of this Letter, the closing bracket was missing; in Extended Data Fig. 1 and the accompanying legend, 'Φ(p d )' should have been 'Φ 2 (p d )', and in the Methods the text "Odd J assignments are uncertain by ±1." has been added. These errors have all been corrected online.

Silicon carbide (SiC) is a compound semiconductor, which is considered as a possible alternative to silicon for particles and photons detection. Its characteristics make it very promising for the next generation of nuclear and particle physics experiments at high beam luminosity. Silicon Carbide detectors for Intense Luminosity Investigations and Applications (SiCILIA) is a project starting as a collaboration between the Italian National Institute of Nuclear Physics (INFN) and IMM-CNR, aiming at the realization of innovative detection systems based on SiC. In this paper, we discuss the main features of silicon carbide as a material and its potential application in the field of particles and photons detectors, the project structure and the strategies used for the prototype realization, and the first results concerning prototype production and their performance.

Carbon burning powers scenarios that influence the fate of stars, such as the late evolutionary stages of massive stars 1 (exceeding eight solar masses) and superbursts from accreting neutron stars 2,3 . It proceeds through the 12 C +  12 C fusion reactions that produce an alpha particle and neon-20 or a proton and sodium-23-that is, 12 C( 12 C, α) 20 Ne and 12 C( 12 C, p) 23 Na-at temperatures greater than 0.4 × 10 9 kelvin, corresponding to astrophysical energies exceeding a megaelectronvolt, at which such nuclear reactions are more likely to occur in stars. The cross-sections 4 for those carbon fusion reactions (probabilities that are required to calculate the rate of the reactions) have hitherto not been measured at the Gamow peaks 4 below 2 megaelectronvolts because of exponential suppression arising from the Coulomb barrier. The reference rate 5 at temperatures below 1.2 × 10 9 kelvin relies on extrapolations that ignore the effects of possible low-lying resonances. Here we report the measurement of the 12 C( 12 C, α 0,1 ) 20 Ne and 12 C( 12 C, p 0,1 ) 23 Na reaction rates (where the subscripts 0 and 1 stand for the ground and first excited states of 20 Ne and 23 Na, respectively) at centre-of-mass energies from 2.7 to 0.8 megaelectronvolts using the Trojan Horse method 6,7 and the deuteron in 14 N. The cross-sections deduced exhibit several resonances that are responsible for very large increases of the reaction rate at relevant temperatures. In particular, around 5 × 10 8 kelvin, the reaction rate is boosted to more than 25 times larger than the reference value 5 . This finding may have implications such as lowering the temperatures and densities 8 required for the ignition of carbon burning in massive stars and decreasing the superburst ignition depth in accreting neutron stars to reconcile observations with theoretical models 3 .

The decay path of the Hoyle state in ^{12}C (E_{x}=7.654  MeV) has been studied with the ^{14}N(d,α_{2})^{12}C(7.654) reaction induced at 10.5 MeV. High resolution invariant mass spectroscopy techniques have allowed us to unambiguously disentangle direct and sequential decays of the state passing through the ground state of ^{8}Be. Thanks to the almost total absence of background and the attained resolution, a fully sequential decay contribution to the width of the state has been observed. The direct decay width is negligible, with an upper limit of 0.043% (95% C.L.). The precision of this result is about a factor 5 higher than previous studies. This has significant implications on nuclear structure, as it provides constraints to 3α cluster model calculations, where higher precision limits are needed.

The (13)C(α,n)(16)O reaction is the neutron source for the main component of the s-process, responsible for the production of most nuclei in the mass range 90

Achalasia is an esophageal motility disorder for which the pathophysiology is only partially known for the idiopathic subtype. Many factors are known to be involved with the development of secondary achalasia. Neurofibromatosis is one of the most common autosomal dominant conditions affecting the nervous system, and 25% of those with the disease have been reported to have involvement of the gastrointestinal tract. Three cases of association between neurofibromatosis and achalasia have been reported in the literature so far. Laparoscopic Heller myotomy is the gold standard surgical treatment for patients with achalasia, whereas esophagectomy is reserved for the more advanced stages of disease. There have been reports of successful long-term results in patients with stage IV achalasia treated with Heller myotomy. We report the fourth case in the literature of association between achalasia and neurofibromatosis; it is the first time that such an association is successfully treated with laparoscopic Heller myotomy.

The 18O(p,alpha)15N reaction is of primary importance in several astrophysical scenarios, including fluorine nucleosynthesis inside asymptotic giant branch stars as well as oxygen and nitrogen isotopic ratios in meteorite grains. Thus the indirect measurement of the low energy region of the 18O(p,alpha)15N reaction has been performed to reduce the nuclear uncertainty on theoretical predictions. In particular the strength of the 20 and 90 keV resonances has been deduced and the change in the reaction rate evaluated.