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Author (down) Plompen, A.J.M. et al; Algora, A.
Title The joint evaluated fission and fusion nuclear data library, JEFF-3.3 Type Journal Article
Year 2020 Publication European Physical Journal A Abbreviated Journal Eur. Phys. J. A
Volume 56 Issue 7 Pages 181 - 108pp
Keywords
Abstract The joint evaluated fission and fusion nuclear data library 3.3 is described. New evaluations for neutron-induced interactions with the major actinides 235U, 238U and 239Pu, on 241Am and 23Na, 59Ni, Cr, Cu, Zr, Cd, Hf, W, Au, Pb and Bi are presented. It includes new fission yields, prompt fission neutron spectra and average number of neutrons per fission. In addition, new data for radioactive decay, thermal neutron scattering, gamma-ray emission, neutron activation, delayed neutrons and displacement damage are presented. JEFF-3.3 was complemented by files from the TENDL project. The libraries for photon, proton, deuteron, triton, helion and alpha-particle induced reactions are from TENDL-2017. The demands for uncertainty quantification in modeling led to many new covariance data for the evaluations. A comparison between results from model calculations using the JEFF-3.3 library and those from benchmark experiments for criticality, delayed neutron yields, shielding and decay heat, reveals that JEFF-3.3 performes very well for a wide range of nuclear technology applications, in particular nuclear energy.
Address [Plompen, A. J. M.; Hambsch, F-J; Kopecky, S.; Schillebeeckx, P.; Zerovnik, G.] Joint Res Ctr, European Commiss, B-2440 Geel, Belgium, Email: arjan.plompen@ec.europa.eu
Corporate Author Thesis
Publisher Springer Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1434-6001 ISBN Medium
Area Expedition Conference
Notes WOS:000553469600001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 4483
Permanent link to this record
 
 
Author (down) Plenter, J.; Rodrigo, G.
Title Asymptotic expansions through the loop-tree duality Type Journal Article
Year 2021 Publication European Physical Journal C Abbreviated Journal Eur. Phys. J. C
Volume 81 Issue 4 Pages 320 - 13pp
Keywords
Abstract Asymptotic expansions of Feynman amplitudes in the loop-tree duality formalism are implemented at integrand-level in the Euclidean space of the loop three-momentum, where the hierarchies among internal and external scales are well-defined. The ultraviolet behaviour of the individual contributions to the asymptotic expansion emerges only in the first terms of the expansion and is renormalized locally in four space-time dimensions. These two properties represent an advantage over the method of Expansion by Regions. We explore different approaches in different kinematical limits, and derive explicit asymptotic expressions for several benchmark configurations.
Address [Plenter, Judith; Rodrigo, German] Univ Valencia, Inst Fis Corpuscular, CSIC, Parc Cient, Valencia 46980, Spain, Email: plenter@ific.uv.es;
Corporate Author Thesis
Publisher Springer Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1434-6044 ISBN Medium
Area Expedition Conference
Notes WOS:000641475900003 Approved no
Is ISI yes International Collaboration no
Call Number IFIC @ pastor @ Serial 4810
Permanent link to this record
 
 
Author (down) Plaza, J.; Martinez, T.; Becares, V.; Cano-Ott, D.; Villamarin, D.; de Rada, A.P.; Mendoza, E.; Pesudo, V.; Santorelli, R.; Pena, C.; Balibrea-Correa, J.; Boeltzig, A.
Title Thermal neutron background at Laboratorio Subterraneo de Canfranc (LSC) Type Journal Article
Year 2023 Publication Astroparticle Physics Abbreviated Journal Astropart Phys.
Volume 146 Issue Pages 102793 - 9pp
Keywords Underground neutron background; Thermal neutron flux; He-3 proportional counter; Pulse shape discrimination
Abstract The thermal neutron background at Laboratorio Subterraneo de Canfranc (LSC) has been determined using several He-3 proportional counter detectors. Bare and Cd shielded counters were used in a series of long measurements. Pulse shape discrimination techniques were applied to discriminate between neutron and gamma signals as well as other intrinsic contributions. Montecarlo simulations allowed us to estimate the sensitivity of the detectors and calculate values for the background flux of thermal neutrons inside Hall-A of LSC. The obtained value is (3.5 +/- 0.8)x10(-6) n/cm(2)s, and is within an order of magnitude compared to similar facilities.
Address [Plaza, J.; Martinez, T.; Becares, V; Cano-Ott, D.; Villamarin, D.; Perez de Rada, A.; Mendoza, E.; Pesudo, V; Santorelli, R.] Ctr Invest Energet Medioambientales & Tecnol CIEM, Ave Complutense 40, Madrid 28040, Spain, Email: julio.plaza@ciemat.es
Corporate Author Thesis
Publisher Elsevier Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0927-6505 ISBN Medium
Area Expedition Conference
Notes WOS:000928281600001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 5482
Permanent link to this record
 
 
Author (down) Plaza, J.; Bécares, V.; Cano-Ott, D.; Gómez, C.; Martínez, T.; Mendoza, E.; Perez de Rada, A.; Pesudo, V.; Sáez-Vergara, J.C.; Santorelli, R.; Villamarín, D.; Ianni, A.; Peña, C.; Balibrea-Correa, J.; Boeltzig, A.; Imbriani, G.
Title CLYC as a neutron detector in low background conditions Type Journal Article
Year 2023 Publication European Physical Journal C Abbreviated Journal Eur. Phys. J. C
Volume 83 Issue 11 Pages 1049 - 10pp
Keywords
Abstract We report on the thermal neutron flux measurements carried out at the Laboratorio Subterraneo de Canfranc (LSC) with two commercial 2 '' x 2 '' CLYC detectors. The measurements were performed as part of an experimental campaign at LSC with He-3 detectors, for establishing the sensitivity limits and use of CLYCs in low background conditions. Acareful characterization of the intrinsic alpha and gamma-ray background in the detectors was required and done with dedicated measurements. It was found that the alpha activities in the two CLYC crystals differ by a factor of three, and the use of Monte Carlo simulations and a Bayesian unfolding method allowed us to determine the specific alpha activities from the U-238 and Th-232 decay chains. The simulations and unfolding also revealed that the gamma-ray background registered in the detectors is dominated by the intrinsic activity of the components of the detector such as the aluminum housing and photo-multiplier and that the activity within the crystal is low in comparison. The data from the neutron flux measurements with the two detectors were analyzed with different methodologies: one based on an innovative alpha/neutron pulse shape discrimination method and one based on the subtraction of the intrinsic alpha background that masks the neutron signals in the region of interest. The neutron sensitivity of the CLYCs was calculated by Monte Carlo simulations with MCNP6 and GEANT4. The resulting thermal neutron fluxes are in good agreement with complementary flux measurement performed with He-3 detectors, but close to the detection limit imposed by the intrinsic a activity.
Address [Plaza, J.; Becares, V.; Cano-Ott, D.; Gomez, C.; Martinez, T.; Mendoza, E.; de Rada, A. Perez; Pesudo, V.; Saez-Vergara, J. C.; Santorelli, R.; Villamarin, D.] Ctr Invest Energet Medioambientales & Tecnol, Avda Complutense 40, Madrid 28040, Spain, Email: julio.plaza@ciemat.es
Corporate Author Thesis
Publisher Springer Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1434-6044 ISBN Medium
Area Expedition Conference
Notes WOS:001105460800003 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 5835
Permanent link to this record
 
 
Author (down) Pla, S.; Winstanley, E.
Title Equivalence of the adiabatic expansion and Hadamard renormalization for a charged scalar field Type Journal Article
Year 2023 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 107 Issue 2 Pages 025004 - 22pp
Keywords
Abstract We examine the relationship between three approaches (Hadamard, DeWitt-Schwinger, and adiabatic) to the renormalization of expectation values of field operators acting on a charged quantum scalar field. First, we demonstrate that the DeWitt-Schwinger representation of the Feynman Green's function is a particular case of the Hadamard representation. Next, we restrict attention to a spatially flat Friedmann-Lemaitre-Robertson-Walker universe with time-dependent, purely electric, background electromagnetic field, considering two-, three-, and four-dimensional space-times. Working to the order required for the renormalization of the stress-energy tensor, we find the adiabatic and DeWitt-Schwinger expansions of the Green's function when the space-time points are spatially separated. In two and four dimensions, the resulting DeWitt-Schwinger and adiabatic expansions are identical. In three dimensions, the DeWittSchwinger expansion contains terms of adiabatic order 4 that are not necessary for the renormalization of the stress-energy tensor and hence absent in the adiabatic expansion. The equivalence of the DeWittSchwinger and adiabatic approaches to renormalization in the scenario considered is thereby demonstrated in even dimensions. In odd dimensions the situation is less clear and further investigation is required in order to determine whether adiabatic renormalization is a locally covariant renormalization prescription.
Address [Pla, Silvia] Kings Coll London, Dept Phys, Strand Bldg,Strand Campus, London WC2R 2LS, England, Email: silvia.pla_garcia@kcl.ac.uk;
Corporate Author Thesis
Publisher Amer Physical Soc Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2470-0010 ISBN Medium
Area Expedition Conference
Notes WOS:001085808200001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 5756
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Author (down) Pla, S.; Newsome, I.M.; Link, R.S.; Anderson, P.R.; Navarro-Salas, J.
Title Pair production due to an electric field in 1+1 dimensions and the validity of the semiclassical approximation Type Journal Article
Year 2021 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 103 Issue 10 Pages 105003 - 23pp
Keywords
Abstract Solutions to the backreaction equation in 1 + 1-dimensional semiclassical electrodynamics are obtained and analyzed when considering a time-varying homogeneous electric field initially generated by a classical electric current, coupled to either a quantized scalar field or a quantized spin-1/2 field. Particle production by way of the Schwinger effect leads to backreaction effects that modulate the electric field strength. Details of the particle production process are investigated along with the transfer of energy between the electric field and the particles. The validity of the semiclassical approximation is also investigated using a criterion previously implemented for chaotic inflation and, in an earlier form, semiclassical gravity. The criterion states that the semiclassical approximation will break down if any linearized gauge-invariant quantity constructed from solutions to the linear response equation, with finite nonsingular data, grows rapidly for some period of time. Approximations to homogeneous solutions of the linear response equation are computed and it is found that the criterion is violated when the maximum value, E-max, obtained by the electric field is of the order of the critical scale for the Schwinger effect, E-max similar to E-crit m(2)/q, where m is the mass of the quantized field and q is its electric charge. For these approximate solutions the criterion appears to be satisfied in the extreme limits qE(max)/m(2) << 1 and qE(max)/m(2) >> 1.
Address [Pla, Silvia; Navarro-Salas, Jose] Univ Valencia, Ctr Mixto Univ Valencia, Fac Fis, CSIC,Dept Fis Teor, E-46100 Valencia, Spain, Email: silvia.pla@uv.es;
Corporate Author Thesis
Publisher Amer Physical Soc Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2470-0010 ISBN Medium
Area Expedition Conference
Notes WOS:000655874700008 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 4844
Permanent link to this record
 
 
Author (down) Piriz, G.H.; Gonzalez-Sprinberg, G.A.; Ballester, F.; Vijande, J.
Title Dosimetry of Large Field Valencia applicators for Cobalt-60-based brachytherapy Type Journal Article
Year 2024 Publication Medical Physics Abbreviated Journal Med. Phys.
Volume Issue Pages 5pp
Keywords dosimetry; Monte Carlo; skin brachytherapy; Valencia applicators
Abstract BackgroundNon-melanoma skin cancer is one of the most common types of cancer and one of the main approaches is brachytherapy. For small lesions, the treatment of this cancer with brachytherapy can be done with two commercial applicators, one of these is the Large Field Valencia Applicators (LFVA).PurposeThe aim of this study is to test the capabilities of the LFVA to use clinically 60Co sources instead of the 192Ir ones. This study was designed for the same dwell positions and weights for both sources.MethodsThe Penelope Monte Carlo code was used to evaluate dose distribution in a water phantom when a 60Co source is considered. The LFVA design and the optimized dwell weights reported for the case of 192Ir are maintained with the only exception of the dwell weight of the central position, that was increased. 2D dose distributions, field flatness, symmetry and the leakage dose distribution around the applicator were calculated.ResultsWhen comparing the dose distributions of both sources, field flatness and symmetry remain unchanged. The only evident difference is an increase of the penumbra regions for all depths when using the 60Co source. Regarding leakage, the maximum dose within the air volume surrounding the applicator is in the order of 20% of the prescription dose for the 60Co source, but it decreases to less than 5% at about 1 cm distance.ConclusionsFlatness and symmetry remains unaltered as compared with 192Ir sources, while an increase in leakage has been observed. This proves the feasibility of using the LFVA in a larger range of clinical applications.
Address [Piriz, Gustavo H.; Gonzalez-Sprinberg, Gabriel A.] Univ Republica, Fac Sci, Med Phys Unit, Montevideo, Uruguay, Email: ghpiriz@gmail.com
Corporate Author Thesis
Publisher Wiley Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0094-2405 ISBN Medium
Area Expedition Conference
Notes WOS:001187737100001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 6011
Permanent link to this record
 
 
Author (down) Pinto-Gomez, F.; De Soto, F.; Ferreira, M.N.; Papavassiliou, J.; Rodriguez-Quintero, J.
Title Lattice three-gluon vertex in extended kinematics: Planar degeneracy Type Journal Article
Year 2023 Publication Physics Letters B Abbreviated Journal Phys. Lett. B
Volume 838 Issue Pages 137737 - 8pp
Keywords QCD; Three-gluon vertex; Lattice QCD; Schwinger-Dyson equations
Abstract We present novel results for the three-gluon vertex, obtained from an extensive quenched lattice simulation in the Landau gauge. The simulation evaluates the transversely projected vertex, spanned on a special tensorial basis, whose form factors are naturally parametrized in terms of individually Bosesymmetric variables. Quite interestingly, when evaluated in these kinematics, the corresponding form factors depend almost exclusively on a single kinematic variable, formed by the sum of the squares of the three incoming four-momenta, q, r, and p. Thus, all configurations lying on a given plane in the coordinate system (q2, r2, p2) share, to a high degree of accuracy, the same form factors, a property that we denominate planar degeneracy. We have confirmed the validity of this property through an exhaustive study of the set of configurations satisfying the condition q2 = r2, within the range [0, 5 GeV]. This drastic simplification allows for a remarkably compact description of the main bulk of the data, which is particularly suitable for future numerical applications. A semi-perturbative analysis reproduces the lattice findings rather accurately, once the inclusion of a gluon mass has cured all spurious divergences.
Address [Pinto-Gomez, F.; De Soto, F.] Univ Pablo de Olavide, Dpto Sistemas Fis Quim & Nat, Seville 41013, Spain, Email: jose.rodriguez@dfaie.uhu.es
Corporate Author Thesis
Publisher Elsevier Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0370-2693 ISBN Medium
Area Expedition Conference
Notes WOS:000953425400001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 5503
Permanent link to this record
 
 
Author (down) Pino, F.; Roe, N.; Orero, A.; Falcon, C.; Rojas, S.; Benlloch, J.M.; Ros, D.; Pavia, J.
Title Development of a variable-radius pinhole SPECT system with a portable gamma camera Type Journal Article
Year 2011 Publication Revista Española de Medicina Nuclear Abbreviated Journal Rev. Esp. Med. Nucl.
Volume 30 Issue 5 Pages 286-291
Keywords SPECT; Small animal; Pinhole; Portable gamma camera; Continuous scintillator
Abstract Objective: To develop a small-animal SPECT system using a low cost commercial portable gamma camera equipped with a pinhole collimator, a continuous scintillation crystal and a position-sensitive photomultiplier tube. Material and methods: The gamma camera was attached to a variable radius system, which enabled us to optimize sensitivity and resolution by adjusting the radius of rotation to the size of the object. To investigate the capability of the SPECT system for small animal imaging, the dependence of resolution and calibration parameters on radius was assessed and acquisitions of small phantoms and mice were carried out. Results: Resolution values, ranging from 1.0 mm for a radius of 21.4 mm and 1.4 mm for a radius of 37.2 mm were obtained, thereby justifying the interest of a variable radius SPECT system. Conclusions: The image quality of phantoms and animals were satisfactory, thus confirming the usefulness of the system for small animal SPECT imaging.
Address [Pino, F; Roe, N; Ros, D] Univ Barcelona, Fac Med, Unitat Biofis, Barcelona 7, Spain, Email: fpino@iconcologia.net
Corporate Author Thesis
Publisher Elsevier Science Inc Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0212-6982 ISBN Medium
Area Expedition Conference
Notes WOS:000294659400004 Approved no
Is ISI yes International Collaboration no
Call Number IFIC @ elepoucu @ Serial 753
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Author (down) Pich, A.; Solomonidi, E.; Vale Silva, L.
Title Final-state interactions in the CP asymmetries of charm-meson two-body decays Type Journal Article
Year 2023 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 108 Issue Pages 036026 - 25pp
Keywords
Abstract Urgent theoretical progress is needed in order to provide an estimate in the Standard Model of the recent measurement by LHCb of direct CP violation in charm-meson two-body decays. Rescattering effects must be taken into account for a meaningful theoretical description of the amplitudes involved in such category of observables, as signaled by the presence of large strong phases. We discuss the computation of the latter effects based on a two-channel coupled dispersion relation, which exploits isospin-zero phase shifts and inelasticity parametrizations of data coming from the rescattering processes ππ→ππ, πK→πK, and ππ→K¯K. The determination of the subtraction constants of the dispersive integrals relies on the leading contributions to the transition amplitudes from the 1/NC counting, where NC is the number of QCD colors. Furthermore, we use the measured values of the branching ratios to help in selecting the nonperturbative inputs in the isospin limit, from which we predict values for the CP asymmetries. We find that the predicted level of CP violation is much below the experimental value.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN ISBN Medium
Area Expedition Conference
Notes Approved no
Is ISI yes International Collaboration no
Call Number IFIC @ pastor @ Serial 6091
Permanent link to this record