560 research outputs found

    The effects of a revised 7^7Be e−^--capture rate on solar neutrino fluxes

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    The electron-capture rate on 7^7Be is the main production channel for 7^7Li in several astrophysical environments. Theoretical evaluations have to account for not only the nuclear interaction, but also the processes in the plasma where 7^7Be ions and electrons interact. In the past decades several estimates were presented, pointing out that the theoretical uncertainty in the rate is in general of few percents. In the framework of fundamental solar physics, we consider here a recent evaluation for the 7^7Be+e−^- rate, not used up to now in the estimate of neutrino fluxes. We analysed the effects of the new assumptions on Standard Solar Models (SSMs) and compared the results obtained by adopting the revised 7^7Be+e−^- rate to those obtained by the one reported in a widely used compilation of reaction rates (ADE11). We found that new SSMs yield a maximum difference in the efficiency of the 7^7Be channel of about -4\% with respect to what is obtained with the previously adopted rate. This fact affects the production of neutrinos from 8^8B, increasing the relative flux up to a maximum of 2.7\%. Negligible variations are found for the physical and chemical properties of the computed solar models. The agreement with the SNO measurements of the neutral current component of the 8^8B neutrino flux is improved.Comment: 7 pages, 3 figures, 4 tables. Accepted for the publication on A&

    Harmonisation Initiatives of Copernicus Data Quality Control

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    The Copernicus Space Component Data Access system (CSCDA) incorporates data contributions from a wide range of satellite missions. Through EO data handling and distribution, CSCDA serves a set of Copernicus Services related to Land, Marine and Atmosphere Monitoring, Emergency Management and Security and Climate Change. The quality of the delivered EO products is the responsibility of each contributing mission, and the Copernicus data Quality Control (CQC) service supports and complements such data quality control activities. The mission of the CQC is to provide a service of quality assessment on the provided imagery, to support the investigation related to product quality anomalies, and to guarantee harmonisation and traceability of the quality information. In terms of product quality control, the CQC carries out analysis of representative sample products for each contributing mission as well as coordinating data quality investigation related to issues found or raised by Copernicus users. Results from the product analysis are systematically collected and the derived quality reports stored in a searchable database. The CQC service can be seen as a privileged focal point with unique comparison capacities over the data providers. The comparison among products from different missions suggests the need for a strong, common effort of harmonisation. Technical terms, definitions, metadata, file formats, processing levels, algorithms, cal/val procedures etc. are far from being homogeneous, and this may generate inconsistencies and confusion among users of EO data. The CSCDA CQC team plays a significant role in promoting harmonisation initiatives across the numerous contributing missions, so that a common effort can achieve optimal complementarity and compatibility among the EO data from multiple data providers. This effort is done in coordination with important initiatives already working towards these goals (e.g. INSPIRE directive, CEOS initiatives, OGC standards, QA4EO etc.). This paper describes the main actions being undertaken by CQC to encourage harmonisation among space-based EO systems currently in service

    NIKEL_AMC: Readout electronics for the NIKA2 experiment

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    The New Iram Kid Arrays-2 (NIKA2) instrument has recently been installed at the IRAM 30 m telescope. NIKA2 is a state-of-art instrument dedicated to mm-wave astronomy using microwave kinetic inductance detectors (KID) as sensors. The three arrays installed in the camera, two at 1.25 mm and one at 2.05 mm, feature a total of 3300 KIDs. To instrument these large array of detectors, a specifically designed electronics, composed of 20 readout boards and hosted in three microTCA crates, has been developed. The implemented solution and the achieved performances are presented in this paper. We find that multiplexing factors of up to 400 detectors per board can be achieved with homogeneous performance across boards in real observing conditions, and a factor of more than 3 decrease in volume with respect to previous generations.Comment: 21 pages; 16 figure

    Trigger and readout electronics for the STEREO experiment

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    The STEREO experiment will search for a sterile neutrino by measuring the anti-neutrino energy spectrum as a function of the distance from the source, the ILL nuclear reactor. A dedicated electronic system, hosted in a single microTCA crate, was designed for this experiment. It performs triggering in two stages with various selectable conditions, processing and readout via UDP/IPBUS of 68 photomultiplier signals continuously digitized at 250 MSPS. Additionally, for detector performance monitoring, the electronics allow on-line calibration by driving LED synchronously with the data acquisition. This paper describes the electronics requirements, architecture and the performances achieved.Comment: Topical Workshop on Electronics for Particle Physics (TWEPP) 2015, Lisboa. 9 pages, 9 figure

    Electronics and data acquisition demonstrator for a kinetic inductance camera

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    A prototype of digital frequency multiplexing electronics allowing the real time monitoring of kinetic inductance detector (KIDs) arrays for mm-wave astronomy has been developed. It requires only 2 coaxial cables for instrumenting a large array. For that, an excitation comb of frequencies is generated and fed through the detector. The direct frequency synthesis and the data acquisition relies heavily on a large FPGA using parallelized and pipelined processing. The prototype can instrument 128 resonators (pixels) over a bandwidth of 125 MHz. This paper describes the technical solution chosen, the algorithm used and the results obtained

    Tecnologie per la didattica musicale: un'esperienza con la realtà virtuale

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    La mobile virtual reality (VR) sta diventando sempre pi\uf9 popolare e accessibile a tutti coloro che possiedono un nuovo smartphone. In particolare, la didattica digitale pu\uf2 trarre vantaggio dall'interazione naturale e dall'immersione in ambienti virtuali, a partire dalla scuola primaria. Questo articolo presenta un quadro tecnico e metodologico a supporto dell'uso della mobile virtual reality nell'istruzione primaria, volto a migliorare l'apprendimento musicale in termini di ascolto attivo, attenzione e tempo. Viene innanzitutto presentata un'applicazione multipiattaforma chiamata VR4EDU, di cui si descrivono le scelte di progetto e lo sviluppo delle applicazioni di virtual reality, con particolare attenzione a una innovativa soluzione di "locomozione virtuale" che risulta essere intuitiva e usabile. Le applicazioni di VR4EDU possono funzionare su hardware a basso costo, diventando quindi appetibili per un uso didattico. L'approccio proposto \ue8 stato validato tramite uno studio con due classi dell'ultimo anno di scuola primaria, incentrato sull'identificazione e l'apprendimento dei generi musicali. Una valutazione preliminare dei risultati mostra un miglioramento nell'apprendimento della caratterizzazione del genere rispetto alle lezioni tradizionali basate su materiale stampato e ascolto passivo

    Generation of an induced pluripotent stem cell line, CSSi011-A (6534), from an Amyotrophic lateral sclerosis patient with heterozygous L145F mutation in SOD1 gene

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    Among the known causative genes of familial ALS, SOD1 mutation is one of the most common. It encodes for the ubiquitous detoxifying copper/zinc binding SOD1 enzyme, whose mutations selectively cause motor neuron death, although the mechanisms are not as yet clear. What is known is that mutant-mediated toxicity is not caused by loss of its detoxifying activity but by a gain-of-function. In order to better understand the pathogenic mechanisms of SOD1 mutation, a human induced pluripotent stem cell (hiPSC) line was generated from the somatic cells of a female patient carrying a missense variation in SOD1 (L145F)

    Effects of Concurrent Resistance and Aerobic Training on Load-Bearing Performance and the Army Physical Fitness Test

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    The purpose of this research was to determine the effects of high intensity endurance training (ET) and resistance training (RT) alone and in combination on various military tasks. Thirty-five male soldiers were randomly assigned to one of four training groups: total body resistance training plus endurance training (RT + ET), upper body resistance training plus endurance training [UB + ET), RT only, and ET only. Training was performed 4 days per week for 12 weeks. Testing occurred before and after the 12-week training regimen. All groups significantly improved push-up performance, whereas only the RT + ET group did not improve sit-up performance. The groups that included ET significantly decreased 2-mile run time, however, only RT + ET and UB + ET showed improved loaded 2-mile run time. Leg power increased for groups that included lower body strengthening exercises (RT and RT + ET). Army Physical Fitness Test performance, loaded running, and leg power responded positively to training, however, it appears there is a high degree of specificity when concurrent training regimens are implemented
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