On particle production for high energy neutrino beams

Analytical formulae for the calculation of secondary particle yields in p-A interactions are given. These formulae can be of great practical importance for fast calculations of neutrino fluxes and for designing new neutrino beam-lines. The formulae are based on a parameterization of the inclusive invariant cross sections for secondary particle production measured in p-Be interactions. Data collected in different energy ranges and kinematic regions are used. The accuracy of the fit to the data with the empirical formulae adopted is within the experimental uncertainties. Prescriptions to extrapolate this parameterization to finite targets and to targets of different materials are given. The results obtained are then used as an input for the simulation of neutrino beams. We show that our approach describes well the main characteristics of measured neutrino spectra at CERN. Thus it may be used in fast simulations aiming at the optimisation of the proposed long-baseline neutrino beams at CERN and FNAL. In particular we will show our predictions for the CNGS beam from CERN to Gran Sasso.Comment: 18 pages, 10 figures. Submitted to The European Physics Journal

The exploitation of bone grease as a nutritive resource: An experimental approach and its implications for the archaeofaunistical record

El presente trabajo tiene como objetivo principal presentar los resultados preliminares obtenidos a partir de un protocolo experimental que permitió evaluar la eficacia de obtener grasa ósea del tejido esponjoso presente en las distintas unidades anatómicas de los ungulados. Dicho recurso se encuentra almacenado principalmente tanto en las trabéculas de las epífisis de los huesos largos como en los elementos del esqueleto axial, siendo necesario para su extracción el hervido de estas partes. Para llevar adelante el experimento se utilizaron elementos tanto axiales (costillas y vertebras) como apendiculares (fémur) de un espécimen subadulto de Ovis aries, los cuales fueron hervidos tanto enteros como fragmentados hasta que no fue posible obtener de ellos más grasa ósea. Los resultados obtenidos permitieron contrastar algunas de las hipótesis planteadas con anterioridad para elementos apendiculares, avalando la idea de que el tejido esponjoso contiene mayor cantidad de grasa ósea y que los fragmentos de menor tamaño presentan mejores rendimientos. Asimismo, los nuevos datos indican que la selección de elementos o porciones de ellos, constituidas en su mayoría por tejido esponjoso, permite potenciar notablemente la obtención de este recurso. Sin embargo, cabe destacar que los valores totales de grasa ósea registrados, siempre fueron bajos, por lo que es esperable que este recurso haya cumplido un rol secundario dentro de la dieta de los cazadores recolectoresThe main aim of this paper is to present the preliminary results obtained from an experimental protocol, which evaluate the efficacy of processing bone grease from the spongy tissue of different anatomical units of ungulates. This resource can be find in long bone epiphysis and in axial element, being necessary for it extraction boiling this parts. To carry out the experiment we used both axial (ribs and vertebra) and appendicular (femur) elements from a young Ovis aries individual. These elements were boiled complete and fragmented until no more grease could be obtain from them. As a result, some previous assumptions of appendicular elements were tested, confirming the idea that spongy tissue have more bone grease and that the smaller fragments are more efficiency. Furthermore, new evidences showed that the selection of element, or part of them, which are mainly constituted of spongy tissue, enhance the extraction of this resource. Nevertheless, the value of bone grease were always low, from which is probably that bone grease played minor role in hunter gatherer diet

Cross-Task and Cross-Lightpath Failure Detection and Localization in Optical Networks Using Transfer Learning

Practical deployments of Machine-Learning(ML)-based solutions for failure management in optical networks often suffer from limited data availability, due to, especially, scarcity of labelled data describing different failure scenarios. Transfer Learning (TL) is regarded as a promising direction in cases of data scarcity, thanks to its ability to transfer knowledge from a Source Domain (SD) (e.g. SD could be a digital twin or a laboratory testbed) to a Target Domain (TD) (e.g., the infield network). In this paper, we focus on cross-lightpath and cross-task application of TL for failure localization and failure detection in optical networks. We found that, depending on the number of retrained parameters in the ML model, cross-lightpath TL for failure localization provides satisfactory accuracy (higher than 90%, in some cases) with limited amounts of TD data, and is also convenient in terms of TD retraining duration with respect to cases where TL is not used. Moreover, we found that cross-task failure detection/localization reaches up to 12% or 25% improvement in TD accuracy when considering failure localization and detection as TD task, respectively

Feasibility of high-voltage systems for a very long drift in liquid argon TPCs

Designs of high-voltage (HV) systems for creating a drift electric field in liquid argon TPCs are reviewed. In ongoing experiments systems capable of approx. 100 kV are realised for a drift field of 0.5-1 kV/cm over a length of up to 1.5 m. Two of them having different approaches are presented: (1) the ICARUS-T600 detector having a system consisting of an external power supply, HV feedthroughs and resistive voltage degraders and (2) the ArDM-1t detector having a cryogenic Greinacher HV multiplier inside the liquid argon volume. For a giant scale liquid argon TPC, a system providing 2 MV may be required to attain a drift length of approx. 20 m. Feasibility of such a system is evaluated by extrapolating the existing designs.Comment: 8 pages, 13 figures, to appear in Proc. of 1st International Workshop towards the Giant Liquid Argon Charge Imaging Experiment (GLA2010), Tsukuba (Japan), March 201

Experimental and Numerical Dynamic Investigation of an ORC System for Waste Heat Recovery Applications in Transportation Sector

ORC power units represent a promising technology for the recovery of waste heat in Internal Combustion Engines (ICEs), allowing to reduce emissions while keeping ICE performance close to expectations. However, the intrinsic transient nature of exhaust gases represents a challenge since it leads ORCs to often work in off-design conditions. It then becomes relevant to study their transient response to optimize performance and prevent main components from operating at inadequate conditions. To assess this aspect, an experimental dynamic analysis was carried out on an ORC-based power unit bottomed to a 3 L Diesel ICE. The adoption of a scroll expander and the control of the pump revolution speed allow a wide operability of the ORC. Indeed, the refrigerant mass flow rate can be adapted according to the exhaust gas thermal power availability in order to increase thermal power recovery from exhaust gases. The experimental data confirmed that when the expander speed is not regulated, it is possible to control the cycle maximum pressure by acting on the refrigerant flow rate. The experimental data have also been used to validate a model developed to extend the analysis beyond the experimental operating limits. It was seen that a 30% mass flow rate increase allowed to raise the plant power from 750 W to 830 W