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Author Ruiz-Femenia, P.; Zahiri-Abyaneh, M.
Title On the minimality of the order p(6) chiral Lagrangian Type Journal Article
Year 2015 Publication Physics Letters B Abbreviated Journal Phys. Lett. B
Volume 751 Issue Pages 256-261
Keywords
Abstract (up) A method to find relations between the operators in the mesonic Lagrangian of Chiral Perturbation Theory at order p(6) is presented. The procedure can be used to establish if the basis of operators in the Lagrangian is minimal. As an example, we apply the method to the two-flavor case in the absence of scalar and pseudo-scalar sources (s = p = 0), and conclude that the minimal Lagrangian contains 27 independent operators.
Address [Ruiz-Femenia, Pedro] Tech Univ Munich, Dept Phys, D-85748 Garching, Germany, Email: pedro.ruiz-femenia@tum.de
Corporate Author Thesis
Publisher Elsevier Science Bv 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:000365384600041 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 2465
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Author Ros, A.; Lerche, C.W.; Sebastia, A.; Sanchez, F.; Benlloch, J.M.
Title Retroreflector arrays for better light collection efficiency of gamma-ray imaging detectors with continuous scintillation crystals without DOI misestimation Type Journal Article
Year 2014 Publication Journal of Instrumentation Abbreviated Journal J. Instrum.
Volume 9 Issue Pages P04009 - 14pp
Keywords Gamma detectors (scintillators, CZT, HPG, HgI etc); Interaction of radiation with matter; Gamma camera, SPECT, PET PET/CT, coronary CT angiography (CTA); Detector design and construction technologies and materials
Abstract (up) A method to improve light collection efficiency of gamma-ray imaging detectors by using retroreflector arrays has been tested, simulations of the behaviour of the scintillation light illuminating the retroreflector surface have been made. Measurements including retroreflector arrays in the setup have also been taken. For the measurements, positron emission tomography (PET) detectors with continuous scintillation crystals have been used. Each detector module consists of a continuous LSO-scintillator of dimensions 49x49x10 mm(3) and a H8500 position-sensitive photo-multiplier (PSPMT) from Hamamatsu. By using a continuous scintillation crystal, the scintillation light distribution has not been destroyed and the energy, the centroids along the x- and y-direction and the depth of interaction (DOI) can be estimated. Simulations have also been run taking into account the use of continuous scintillation crystals. Due to the geometry of the continuous scintillation crystals in comparison with pixelated crystals, a good light collection efficiency is necessary to correctly reconstruct the impact point of the gamma-ray. The aim of this study is to investigate whether micro-machine retro-reflectors improve light yield without misestimation of the impact point. The results shows an improvement on the energy and centroid resolutions without worsening the depth of interaction resolution. Therefore it can be concluded that using retroreflector arrays at the entrance side of the scintillation crystal improves light collection efficiency without worsening the impact point estimation.
Address [Ros, A.] Inst Fis Corpuscular IFIC, Valencia 46980, Spain, Email: anrogar2@i3m.upv.es
Corporate Author Thesis
Publisher Iop Publishing Ltd Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1748-0221 ISBN Medium
Area Expedition Conference
Notes WOS:000336123800049 Approved no
Is ISI yes International Collaboration no
Call Number IFIC @ pastor @ Serial 1798
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Author Chiera, N.M.; Maugeri, E.A.; Danilov, I.; Balibrea-Correa, J.; Domingo-Pardo, C.; Koster, U.; Lerendegui-Marco, J.; Veicht, M.; Zivadinovic, I.; Schumann, D.
Title Preparation of PbSe targets for Se-79 neutron capture cross section studies Type Journal Article
Year 2022 Publication Nuclear Instruments & Methods in Physics Research A Abbreviated Journal Nucl. Instrum. Methods Phys. Res. A
Volume 1029 Issue Pages 166443 - 7pp
Keywords Lead selenide; Selenium-79; Neutron capture; PbSe target; Se separation
Abstract (up) A methodology for the production of PbSe targets for Se-79 neutron capture cross section studies is presented. PbSe material was synthesized by direct reaction of its constituents at high temperature, and characterized by X-ray diffraction. Thin PbSe targets, produced for cross section experiments with the surrogate reaction method, were obtained by applying a physical vapor deposition technique, and their morphology and composition were analyzed by X-ray fluorescence, Scanning Electron Microscopy, and Energy dispersive X-ray spectroscopy. (PbSe)-Se-79 targets produced for cross section measurements with the Time of Flight method were characterized by gamma-ray spectroscopy. Finally, a procedure for the recovery of Se from PbSe is suggested. The purity of the retrieved Se was determined with Inductively Coupled Plasma Optical Emission Spectroscopy.
Address [Chiera, Nadine M.; Maugeri, Emilio Andrea; Danilov, Ivan; Veicht, Mario; Zivadinovic, Ivan; Schumann, Dorothea] Paul Scherrer Inst, Villigen, Switzerland, Email: nadine-mariel.chiera@psi.ch
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 0168-9002 ISBN Medium
Area Expedition Conference
Notes WOS:000783012200016 Approved no
Is ISI yes International Collaboration no
Call Number IFIC @ pastor @ Serial 5204
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Author Bazeia, D.; Losano, L.; Olmo, G.J.; Rubiera-Garcia, D.; Sanchez-Puente, A.
Title Classical resolution of black hole singularities in arbitrary dimension Type Journal Article
Year 2015 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 92 Issue 4 Pages 044018 - 15pp
Keywords
Abstract (up) A metric-affine approach is employed to study higher-dimensional modified gravity theories involving different powers and contractions of the Ricci tensor. It is shown that the field equations are always second-order, as opposed to the standard metric approach, where this is only achieved for Lagrangians of the Lovelock type. We point out that this property might have relevant implications for the AdS/CFT correspondence in black hole scenarios. We illustrate these aspects by considering the case of Born-Infeld gravity in d dimensions, where we work out exact solutions for electrovacuum configurations. Our results put forward that black hole singularities in arbitrary dimensions can be cured in a purely classical geometric scenario governed by second-order field equations.
Address [Bazeia, D.; Losano, L.; Olmo, Gonzalo J.] Univ Fed Paraiba, Dept Fis, BR-58051900 Joao Pessoa, Paraiba, Brazil, Email: bazeia@fisica.ufpb.br;
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 1550-7998 ISBN Medium
Area Expedition Conference
Notes WOS:000359443800002 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 2362
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Author Albaladejo, M.; Moussallam, B.
Title Form factors of the isovector scalar current and the eta pi scattering phase shifts Type Journal Article
Year 2015 Publication European Physical Journal C Abbreviated Journal Eur. Phys. J. C
Volume 75 Issue 10 Pages 488 - 16pp
Keywords
Abstract (up) A model for S-wave eta pi scattering is proposed which could be realistic in an energy range from threshold up to above 1 GeV, where inelasticity is dominated by the K (K) over bar channel. The T-matrix, satisfying two-channel unitarity, is given in a form which matches the chiral expansion results at order p(4) exactly for the eta pi -> eta pi, eta pi -> K (K) over bar amplitudes and approximately for K (K) over bar -> K (K) over bar. It contains six phenomenological parameters. Asymptotic conditions are imposed which ensure a minimal solution of the Muskhelishvili-Omnes problem, thus allowing one to compute the eta pi and K (K) over bar form factor matrix elements of the I = 1 scalar current from the T-matrix. The phenomenological parameters are determined such as to reproduce the experimental properties of the a(0)(980), a(0)(1450) resonances, as well as the chiral results of the eta pi and K (K) over bar scalar radii, which are predicted to be remarkably small at O(p(4)). This T-matrix model could be used for a unified treatment of the eta pi final-state interaction problem in processes such as eta ' -> eta pi pi, phi -> eta pi gamma or the eta pi initial-state interaction in eta -> 3 pi.
Address [Albaladejo, M.; Moussallam, B.] Univ Paris 11, Grp Phys Theor, IPN UMR8608, Orsay, France, Email: Miguel.Albaladejo@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:000362951600001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 2415
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