139 research outputs found
Results for the response function determination of the Compact Neutron Spectrometer
The Compact Neutron Spectrometer (CNS) is a Joint European Torus (JET)
Enhancement Project, designed for fusion diagnostics in different plasma
scenarios. The CNS is based on a liquid scintillator (BC501A) which allows good
discrimination between neutron and gamma radiation. Neutron spectrometry with a
BC501A spectrometer requires the use of a reliable, fully characterized
detector. The determination of the response matrix was carried out at the Ion
Accelerator Facility (PIAF) of the Physikalisch-Technische Bundesanstalt (PTB).
This facility provides several monoenergetic beams (2.5, 8, 10, 12 and 14 MeV)
and a 'white field'(Emax ~17 MeV), which allows for a full characterization of
the spectrometer in the region of interest (from ~1.5 MeV to ~17 MeV. The
energy of the incoming neutrons was determined by the time of flight method
(TOF), with time resolution in the order of 1 ns. To check the response matrix,
the measured pulse height spectra were unfolded with the code MAXED and the
resulting energy distributions were compared with those obtained from TOF. The
CNS project required modification of the PTB BC501A spectrometer design, to
replace an analog data acquisition system (NIM modules) with a digital system
developed by the 'Ente per le Nuove tecnologie, l'Energia e l'Ambiente' (ENEA).
Results for the new digital system were evaluated using new software developed
specifically for this project.Comment: Proceedings of FNDA 201
Energy sustainability in teaching and outreach initiatives and the contribution to the 2030 Agenda
© 2020, Emerald Publishing Limited. Purpose: Considering the different roles universities can perform to contribute to sustainable development, it is through teaching and outreach that they might be able to connect to the academic and local communities the most. The purpose of this study is to investigate the extent to which energy sustainability is being considered in campus teaching and outreach activities of different higher education institutions worldwide. In this context, this exploratory study was developed. Design/methodology/approach: Through an online survey, a group of 36 universities from all continents was inquired about the level of sustainability in energy aspects of teaching and outreach activities, including curriculum change, training courses for staff and the regularity of outreach projects. Findings: The results allowed global analysis concerning challenges and opportunities of these educational activities. This study also touches upon the interconnection between these practices and the contribution of universities towards the 2030 Agenda, and how universities can expand their activities and contribute practically to society. In terms of practical contributions, this study provides recommendations for higher education institutions to develop further in the area of energy sustainability through teaching and outreach. Originality/value: Energy is a sustainability aspect relatively well covered by actions on campus operations, but there is a paucity of studies connecting this topic to teaching and outreach activities. This study is an approach to not only fill this gap but also reinforce the university role and contribution to the Sustainable Development Goals
Neutron-induced background in the CONUS experiment
CONUS is a novel experiment aiming at detecting elastic neutrino nucleus
scattering in the fully coherent regime using high-purity Germanium (Ge)
detectors and a reactor as antineutrino () source. The detector setup
is installed at the commercial nuclear power plant in Brokdorf, Germany, at a
very small distance to the reactor core in order to guarantee a high flux of
more than 10/(scm). For the experiment, a good
understanding of neutron-induced background events is required, as the neutron
recoil signals can mimic the predicted neutrino interactions. Especially
neutron-induced events correlated with the thermal power generation are
troublesome for CONUS. On-site measurements revealed the presence of a thermal
power correlated, highly thermalized neutron field with a fluence rate of
(74530)cmd. These neutrons that are produced by nuclear
fission inside the reactor core, are reduced by a factor of 10 on
their way to the CONUS shield. With a high-purity Ge detector without shield
the -ray background was examined including highly thermal power
correlated N decay products as well as -lines from neutron
capture. Using the measured neutron spectrum as input, it was shown, with the
help of Monte Carlo simulations, that the thermal power correlated field is
successfully mitigated by the installed CONUS shield. The reactor-induced
background contribution in the region of interest is exceeded by the expected
signal by at least one order of magnitude assuming a realistic ionization
quenching factor of 0.2.Comment: 28 pages, 28 figure
Statistical Origin of Quantum Mechanics
The one particle quantum mechanics is considered in the frame of a N-body
classical kinetics in the phase space. Within this framework, the scenario of a
subquantum structure for the quantum particle, emerges naturally, providing an
ontological support to the orthodox quantum mechanics. This approach to quantum
mechanics, constitutes a deductive and direct method which, in a
self-consistent scheme of a classical kinetics, allows us: i) to obtain the
probabilistic nature of the quantum description and to interpret the wave
function according to the Copenhagen school; ii) to derive the quantum
potential and then the Schr\"odinger equation; iii) to calculate the values of
the physical observables as mean values of the associated quantum operators;
iv) to obtain the Heisenberg uncertainty principle.Comment: Accepted for publication in Physica
Classical-Quantum Coexistence: a `Free Will' Test
Von Neumann's statistical theory of quantum measurement interprets the
instantaneous quantum state and derives instantaneous classical variables. In
realty, quantum states and classical variables coexist and can influence each
other in a time-continuous way. This has been motivating investigations since
longtime in quite different fields from quantum cosmology to optics as well as
in foundations. Different theories (mean-field, Bohm, decoherence, dynamical
collapse, continuous measurement, hybrid dynamics, e.t.c.) emerged for what I
call `coexistence of classical continuum with quantum'. I apply to these
theories a sort of `free will' test to distinguish `tangible' classical
variables useful for causal control from useless ones.Comment: 7pp, based on talk at Conf. on Emergent Quantum Mechanics, Heinz von
Foerster Congress (Vienna University, Nov 11-13, 2011
Sustainable development goals: a framework for deploying indicators for higher education institutions
Purpose: This paper aims to analyse the extent to which the sustainable development goals (SDGs) are being considered at higher education institutions (HEIs) and propose and test the possible acceptance of a list of indicators to evaluate the contribution of HEIs to the SDGs. Design/methodology/approach: The methodology consisted of the collection of indicators of sustainable development based on the existing bibliography. Afterwards, a set of indicators related to the SDGs were selected, based on the most frequent SDGs’ expressions found in the selected indicators. A sample of researchers was also asked to indicate to which extent this set of indicators is perceived as relevant. Findings: The results indicated an initial list with 432 indicators, of which 268 were selected for having at least one of the keywords searched for, related to the SDG descriptions and targets. Thus, redundant indicators were excluded and, when necessary, indicators were aggregated, resulting in a final list of 61 indicators. Originality/value: The set of indicators resulted from this analysis was considered appropriate to evaluate the contribution of HEIs towards the SDGs, demonstrating that it might not be necessary to create new indicators for that purpose
General linear dynamics - quantum, classical or hybrid
We describe our recent proposal of a path integral formulation of classical
Hamiltonian dynamics. Which leads us here to a new attempt at hybrid dynamics,
which concerns the direct coupling of classical and quantum mechanical degrees
of freedom. This is of practical as well as of foundational interest and no
fully satisfactory solution of this problem has been established to date.
Related aspects will be observed in a general linear ensemble theory, which
comprises classical and quantum dynamics in the form of Liouville and von
Neumann equations, respectively, as special cases. Considering the simplest
object characterized by a two-dimensional state-space, we illustrate how
quantum mechanics is special in several respects among possible linear
generalizations.Comment: 17 pages; based on invited talks at the conferences DICE2010
(Castiglioncello, Italia, Sept 13-17, 2010) and Quantum Field Theory and
Gravity (Regensburg, Germany, Sept 28 - Oct 1, 2010
Direction distributions of neutrons and reference values of the personal dose equivalent in workplace fields
Within the EC project EVIDOS, double-differential (energy and direction) fluence spectra were determined by means of novel direction spectrometers. By folding the spectra with fluence-to-dose equivalent conversion coefficients, contributions to H*(10) for 14 directions, and values of the personal dose equivalent Hp(10) and the effective dose E for 6 directions of a person's orientation in the field were determined. The results of the measurements and calculations obtained within the EVIDOS project in workplace fields in nuclear installations in Europe, i.e., at Krümmel (boiling water reactor and transport cask), at Mol (Venus research reactor and fuel facility Belgonucléaire) and at Ringhals (pressurised reactor and transport cask) are presente
Characterisation of mixed neutron-photon workplace fields at nuclear facilities by spectrometry (energy and direction) within the EVIDOS project
Within the EC project EVIDOS, 17 different mixed neutron-photon workplace fields at nuclear facilities (boiling water reactor, pressurised water reactor, research reactor, fuel processing, storage of spent fuel) were characterised using conventional Bonner sphere spectrometry and newly developed direction spectrometers. The results of the analysis, using Bayesian parameter estimation methods and different unfolding codes, some of them especially adapted to simultaneously unfold energy and direction distributions of the neutron fluence, showed that neutron spectra differed strongly at the different places, both in energy and direction distribution. The implication of the results for the determination of reference values for radiation protection quantities (ambient dose equivalent, personal dose equivalent and effective dose) and the related uncertainties are discusse
Contribution to understanding the mathematical structure of quantum mechanics
Probabilistic description of results of measurements and its consequences for
understanding quantum mechanics are discussed. It is shown that the basic
mathematical structure of quantum mechanics like the probability amplitudes,
Born rule, commutation and uncertainty relations, probability density current,
momentum operator, rules for including the scalar and vector potentials and
antiparticles can be obtained from the probabilistic description of results of
measurement of the space coordinates and time. Equations of motion of quantum
mechanics, the Klein-Gordon equation, Schrodinger equation and Dirac equation
are obtained from the requirement of the relativistic invariance of the
space-time Fisher information. The limit case of the delta-like probability
densities leads to the Hamilton-Jacobi equation of classical mechanics. Many
particle systems and the postulates of quantum mechanics are also discussed.Comment: 21 page
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