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Author Amarilo, K.M.; Ferreira Filho, M.B.; Araujo Filho, A.A.; Reis, J.A.A.S.
Title Gravitational waves effects in a Lorentz-violating scenario Type Journal Article
Year 2024 Publication (down) Physics Letters B Abbreviated Journal Phys. Lett. B
Volume 855 Issue Pages 138785 - 7pp
Keywords Gravitational waves; Lorentz symmetry breaking; Polarization states; Quadrupole term
Abstract This paper focuses on how the production and polarization of gravitational waves are affected by spontaneous Lorentz symmetry breaking, which is driven by a self-interacting vector field. Specifically, we examine the impact of a smooth quadratic potential and a non-minimal coupling, discussing the constraints and causality features of the linearized Einstein equation. To analyze the polarization states of a plane wave, we consider a fixed vacuum expectation value (VEV) of the vector field. Remarkably, we verify that a space-like background vector field modifies the polarization plane and introduces a longitudinal degree of freedom. In order to investigate the Lorentz violation effect on the quadrupole formula, we use the modified Green function. Finally, we show that the space-like component of the background field leads to a third-order time derivative of the quadrupole moment, and the bounds for the Lorentz-breaking coefficients are estimated as well.
Address [Amarilo, K. M.; Ferreira Filho, M. B.] Univ Estado Rio de Janeiro, Dep Fis Nucl & Altas Energias, Inst Fis, Rua Sao Francisco Xavier 524, BR-20559900 Rio De Janeiro, RJ, Brazil, Email: kevin.amarilo@cern.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 0370-2693 ISBN Medium
Area Expedition Conference
Notes WOS:001257664300001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 6168
Permanent link to this record
 

 
Author Belchior, F.M.; Maluf, R.
Title Duality between the Maxwell-Chern-Simons and self-dual models in very special relativity Type Journal Article
Year 2024 Publication (down) Physics Letters B Abbreviated Journal Phys. Lett. B
Volume 855 Issue Pages 138794 - 7pp
Keywords Duality; Very special relativity; Maxwell-Chern-Simons theory
Abstract This work investigates the classical and quantum duality between the SIM (1)-Maxwell-Chern-Simons (MCS) model and its self -dual counterpart. Initially, we focus on free -field cases to establish equivalence through two distinct approaches: comparing the equations of motion and utilizing the master Lagrangian method. In both instances, the classical correspondence between the self -dual and MCS dual fields undergoes modifications due to very special relativity (VSR). Specifically, the duality is established when the associated VSR-mass parameters are identical, and the dual field is introduced through a non -local VSR correction. Furthermore, we analyze the duality when the self -dual model is minimally coupled to fermions. As a result, we demonstrate that Thirring-like interactions, corrected for non -local VSR contributions, are included in the MCS model. Additionally, we establish the quantum equivalence of the models by performing a functional integration of the fields and comparing the resulting effective Lagrangians.
Address [Belchior, Fernando M.; Maluf, Roberto, V] Univ Fed Ceara UFC, Dept Fis, Campus Pici,CP 6030, BR-60455760 Fortaleza, CE, Brazil, Email: belchior@fisica.ufc.br
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:001259074700001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 6174
Permanent link to this record
 

 
Author Aad, G.
Title Measurement of vector boson production cross sections and their ratios using pp collisions at √s=13.6 TeV with the ATLAS detector Type Journal Article
Year 2024 Publication (down) Physics Letters B Abbreviated Journal Phys. Lett. B
Volume 854 Issue Pages 138725 - 27pp
Keywords
Abstract Fiducial and total W+ and Z boson cross sections, their ratios and the ratio of top-antitop-quark pair and.. -boson fiducial cross sections are measured in proton-proton collisions at a centre-of-mass energy of root s = 13.6 TeV, corresponding to an integrated luminosity of 29 fb(-1) of data collected in 2022 by the ATLAS experiment at the Large Hadron Collider. The measured fiducial cross-section values for W+ -> l(+) v, W- -> l(-) v- <overline>, and Z -> l(+)l(-) (l =e or mu) boson productions are 4250 +/- 150 pb, 3310 +/- 120 pb, and 744 +/- 20 pb, respectively, where the uncertainty is the total uncertainty, including that arising from the luminosity of about 2.2%. The measurements are in agreement with Standard-Model predictions calculated at next-to-next-to-leading-order in alpha(s) ,next-to-nextto-leading logarithmic accuracy and next-to-leading-order electroweak accuracy.
Address [Filmer, E. K.; Grant, C. M.; Jackson, P.; Kong, A. X. Y.; Pandya, H. D.; Ruggeri, T. A.; Saha, S.; Ting, E. X. L.; White, M. J.] Univ Adelaide, Dept Phys, Adelaide, SA, Australia
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:001261443900001 Approved no
Is ISI International Collaboration
Call Number IFIC @ pastor @ Serial 6190
Permanent link to this record
 

 
Author Aad, G.
Title Measurement of the Higgs boson mass in the H → Z Z* → 4l decay channel using 139 fb-1 of √s=13 TeV pp collisions recorded by the ATLAS detector at the LHC br Type Journal Article
Year 2023 Publication (down) Physics Letters B Abbreviated Journal Phys. Lett. B
Volume 843 Issue Pages 137880 - 23pp
Keywords
Abstract The mass of the Higgs boson is measured in the H -> Z Z* -> 4l decay channel. The analysis uses proton-proton collision data from the Large Hadron Collider at a centre-of-mass energy of 13 TeV recorded by the ATLAS detector between 2015 and 2018, corresponding to an integrated luminosity of 139 fb(-1). The measured value of the Higgs boson mass is 124.99 0.18(stat.) +/- 0.04(syst.) GeV. In final states with muons, this measurement benefits from an improved momentum-scale calibration relative to that adopted in previous publications. The measurement also employs an analytic model that takes into account the invariant-mass resolution of the four-lepton system on a per-event basis and the output of a deep neural network discriminating signal from background events. This measurement is combined with the corresponding measurement using 7 and 8 TeV pp collision data, resulting in a Higgs boson mass of 124.94 +/- 0.17(stat.) +/- 0.03(syst.) GeV. (c) 2023 The Author(s). Published by Elsevier B.V. This is an open access article under the CC BY license (http://creativecommons .org /licenses /by /4 .0/). Funded by SCOAP3.
Address [Amerl, M.; Filmer, E. K.; Jackson, P.; Kong, A. X. Y.; Potti, H.; Ruggeri, T. A.; Ting, E. X. L.; White, M. J.] Univ Adelaide, Dept Phys, Adelaide, Australia
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:001256747200001 Approved no
Is ISI International Collaboration
Call Number IFIC @ pastor @ Serial 6194
Permanent link to this record
 

 
Author Aad, G.
Title Measurement of the charge asymmetry in top-quark pair production in association with a photon with the ATLAS experiment Type Journal Article
Year 2023 Publication (down) Physics Letters B Abbreviated Journal Phys. Lett. B
Volume 843 Issue Pages 137848 - 21pp
Keywords
Abstract A measurement of the charge asymmetry in top-quark pair (t (t) over bar) production in association with a photon is presented. The measurement is performed in the single-lepton t (t) over bar decay channel using proton-proton collision data collected with the ATLAS detector at the Large Hadron Collider at CERN at a centre-of-mass-energy of 13 TeV during the years 2015-2018, corresponding to an integrated luminosity of 139 fb(-1). The charge asymmetry is obtained from the distribution of the difference of the absolute rapidities of the top quark and antiquark using a profile likelihood unfolding approach. It is measured to be A(C) = -0.003 +/- 0.029 in agreement with the Standard Model expectation. (c) 2023 The Author(s). Published by Elsevier B.V. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/).
Address [Ames, C. G.; Filmer, E. K.; Jackson, P.; Kong, A. X. Y.; Potti, H.; Ruggeri, T. A.; Ting, E. X. L.; White, M. J.] Univ Adelaide, Dept Phys, Adelaide, SA, Australia
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:001256753500001 Approved no
Is ISI International Collaboration
Call Number IFIC @ pastor @ Serial 6195
Permanent link to this record
 

 
Author Aad, G.
Title Measurement of the cross-sections of the electroweak and total production of a Zγ pair in association with two jets in pp collisions at √s=13 TeV with the ATLAS detector Type Journal Article
Year 2023 Publication (down) Physics Letters B Abbreviated Journal Phys. Lett. B
Volume 846 Issue Pages 138222 - 30pp
Keywords
Abstract This Letter presents the measurement of the fiducial and differential cross-sections of the electroweak production of a Z gamma pair in association with two jets. The analysis uses 140 fb(-1)of LHC proton-proton collision data taken at root s=13 TeV recorded by the ATLAS detector during the years 2015-2018. Events with a Zboson candidate decaying into either an e(+) e(-) or mu(+) mu(-) pair, a photon and two jets are selected. The electroweak component is extracted by requiring a large dijet invariant mass and by using the information about the centrality of the system and is measured with an observed and expected significance well above five standard deviations. The fiducial pp -> Z gamma jj cross-section for the electroweak production is measured to be 3.6 +/- 0.5fb. The total fiducial cross-section that also includes contributions where the jets arise from strong interactions is measured to be 16.8(-1.8)(+2.0) fb. The results are consistent with the Standard Model predictions. Differential cross-sections are also measured using the same events and are compared with parton-shower Monte Carlo simulations. Good agreement is observed between data and predictions. (c) 2023 The Author(s). Published by Elsevier B.V. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/).
Address [Filmer, E. K.; Grant, C. M.; Jackson, P.; Kong, A. X. Y.; Pandya, H. D.; Potti, H.; Ruggeri, T. A.; Ting, E. X. L.; White, M. J.] Univ Adelaide, Dept Phys, Adelaide, SA, Australia
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:001257131700001 Approved no
Is ISI International Collaboration
Call Number IFIC @ pastor @ Serial 6196
Permanent link to this record
 

 
Author Etxebeste, A.; Barrio, J.; Muñoz, E.; Oliver, J.F.; Solaz, C.; Llosa, G.
Title 3D position determination in monolithic crystals coupled to SiPMs for PET Type Journal Article
Year 2016 Publication (down) Physics in Medicine and Biology Abbreviated Journal Phys. Med. Biol.
Volume 61 Issue 10 Pages 3914-3934
Keywords monolithic crystal; silicon photomultiplier; depth of interaction
Abstract The interest in using continuous monolithic crystals in positron emission tomography (PET) has grown in the last years. Coupled to silicon photomultipliers (SiPMs), the detector can combine high sensitivity and high resolution, the two main factors to be maximized in a positron emission tomograph. In this work, the position determination capability of a detector comprised of a 12 x 12 x 10 mm(3) LYSO crystal coupled to an 8 x 8-pixel array of SiPMs is evaluated. The 3D interaction position of.-rays is estimated using an analytical model of the light distribution including reflections on the facets of the crystal. Monte Carlo simulations have been performed to evaluate different crystal reflectors and geometries. The method has been characterized and applied to different cases. Intrinsic resolution obtained with the position estimation method used in this work, applied to experimental data, achieves sub-millimetre resolution values. Average resolution over the detector surface for 5 mm thick crystal is similar to 0.9 mm FWHM and similar to 1.2 mm FWHM for 10 mm thick crystal. Depth of interaction resolution is close to 2 mm FWHM in both cases, while the FWTM is similar to 5.3 mm for 5 mm thick crystal and similar to 9.6 mm for 10 mm thick crystal.
Address [Etxebeste, Ane; Barrio, John; Munoz, Enrique; Oliver, Josep F.; Solaz, Carles; Llosa, Gabriela] Univ Valencia, CSIC, Inst Fis Corpuscular, Valencia, Spain, Email: ane.etxebeste@ific.uv.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 0031-9155 ISBN Medium
Area Expedition Conference
Notes WOS:000376792800014 Approved no
Is ISI yes International Collaboration no
Call Number IFIC @ pastor @ Serial 2708
Permanent link to this record
 

 
Author Solevi, P.; Muñoz, E.; Solaz, C.; Trovato, M.; Dendooven, P.; Gillam, J.E.; Lacasta, C.; Oliver, J.F.; Rafecas, M.; Torres-Espallardo, I.; Llosa, G.
Title Performance of MACACO Compton telescope for ion-beam therapy monitoring: first test with proton beams Type Journal Article
Year 2016 Publication (down) Physics in Medicine and Biology Abbreviated Journal Phys. Med. Biol.
Volume 61 Issue 14 Pages 5149-5165
Keywords ion-beam therapy; range verification; prompt gamma; Compton camera; GATE
Abstract In order to exploit the advantages of ion-beam therapy in a clinical setting, delivery verification techniques are necessary to detect deviations from the planned treatment. Efforts are currently oriented towards the development of devices for real-time range monitoring. Among the different detector concepts proposed, Compton cameras are employed to detect prompt gammas and represent a valid candidate for real-time range verification. We present the first on-beam test of MACACO, a Compton telescope (multi-layer Compton camera) based on lanthanum bromide crystals and silicon photo-multipliers. The Compton telescope was first characterized through measurements and Monte Carlo simulations. The detector linearity was measured employing Na-22 and Am-Be sources, obtaining about 10% deviation from linearity at 3.44 MeV. A spectral image reconstruction algorithm was tested on synthetic data. Point-like sources emitting gamma rays with energy between 2 and 7 MeV were reconstructed with 3-5 mm resolution. The two-layer Compton telescope was employed to measure radiation emitted from a beam of 150 MeV protons impinging on a cylindrical PMMA target. Bragg-peak shifts were achieved via adjustment of the PMMA target location and the resulting measurements used during image reconstruction. Reconstructed Bragg peak profiles proved sufficient to observe peak-location differences within 10 mm demonstrating the potential of the MACACO Compton Telescope as a monitoring device for ion-beam therapy.
Address [Solevi, Paola; Munoz, Enrique; Solaz, Carles; Trovato, Marco; Gillam, John E.; Lacasta, Carlos; Oliver, Josep F.; Rafecas, Magdalena; Torres-Espallardo, Irene; Llosa, Gabriela] IFIC CSIC UVEG, Inst Fis Corpuscular, Valencia, Spain, Email: paola.solevi@ovgu.de
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 0031-9155 ISBN Medium
Area Expedition Conference
Notes WOS:000379555300007 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 2754
Permanent link to this record
 

 
Author Muñoz, E.; Barrio, J.; Etxebeste, A.; Ortega, P.G.; Lacasta, C.; Oliver, J.F.; Solaz, C.; Llosa, G.
Title Performance evaluation of MACACO: a multilayer Compton camera Type Journal Article
Year 2017 Publication (down) Physics in Medicine and Biology Abbreviated Journal Phys. Med. Biol.
Volume 62 Issue 18 Pages 7321-7341
Keywords Compton imaging; Compton camera; continuous LaBr3 crystal; silicon photomultiplier; hadron therapy
Abstract Compton imaging devices have been proposed and studied for a wide range of applications. We have developed a Compton camera prototype which can be operated with two or three detector layers based on monolithic lanthanum bromide (LaBr3) crystals coupled to silicon photomultipliers (SiPMs), to be used for proton range verification in hadron therapy. In this work, we present the results obtained with our prototype in laboratory tests with radioactive sources and in simulation studies. Images of a Na-22 and an Y-88 radioactive sources have been successfully reconstructed. The full width half maximum of the reconstructed images is below 4 mm for a Na-22 source at a distance of 5 cm.
Address [Munoz, Enrique; Barrio, John; Etxebeste, Ane; Ortega, Pablo G.; Lacasta, Carlos; Oliver, Josep F.; Solaz, Carles; Llosa, Gabriela] Univ Valencia, CSIC, Inst Fis Corpuscular, Valencia, Spain, Email: Enrique.Munoz@ific.uv.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 0031-9155 ISBN Medium
Area Expedition Conference
Notes WOS:000408229900003 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 3253
Permanent link to this record
 

 
Author Gimenez-Alventosa, V.; Gimenez, V.; Ballester, F.; Vijande, J.; Andreo, P.
Title Correction factors for ionization chamber measurements with the 'Valencia' and 'large field Valencia' brachytherapy applicators Type Journal Article
Year 2018 Publication (down) Physics in Medicine and Biology Abbreviated Journal Phys. Med. Biol.
Volume 63 Issue 12 Pages 125004 - 10pp
Keywords skin applicator; Valencia applicator; large field Valencia applicator; HDR brachytherap; brachytherapy dosimetry; Monte Carlo
Abstract Treatment of small skin lesions using HDR brachytherapy applicators is a widely used technique. The shielded applicators currently available in clinical practice are based on a tungsten-alloy cup that collimates the source-emitted radiation into a small region, hence protecting nearby tissues. The goal of this manuscript is to evaluate the correction factors required for dose measurements with a plane-parallel ionization chamber typically used in clinical brachytherapy for the 'Valencia' and 'large field Valencia' shielded applicators. Monte Carlo simulations have been performed using the PENELOPE-2014 system to determine the absorbed dose deposited in a water phantom and in the chamber active volume with a Type A uncertainty of the order of 0.1%. The average energies of the photon spectra arriving at the surface of the water phantom differ by approximately 10%, being 384 keV for the 'Valencia' and 343 keV for the 'large field Valencia'. The ionization chamber correction factors have been obtained for both applicators using three methods, their values depending on the applicator being considered. Using a depth-independent global chamber perturbation correction factor and no shift of the effective point of measurement yields depth-dose differences of up to 1% for the 'Valencia' applicator. Calculations using a depth-dependent global perturbation factor, or a shift of the effective point of measurement combined with a constant partial perturbation factor, result in differences of about 0.1% for both applicators. The results emphasize the relevance of carrying out detailed Monte Carlo studies for each shielded brachytherapy applicator and ionization chamber.
Address [Gimenez-Alventosa, V.] Univ Politecn Valencia, CSIC, Ctr Mixto, Inst Instrumentac Imagen Mol I3M, E-46022 Valencia, Spain, Email: Javier.vijande@uv.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 0031-9155 ISBN Medium
Area Expedition Conference
Notes WOS:000434682500004 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 3609
Permanent link to this record