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Author Aguilar, A.C.; Ferreira, M.N.; Papavassiliou, J.; Santos, L.R.
Title Four-gluon vertex in collinear kinematics Type Journal Article
Year 2024 Publication European Physical Journal C Abbreviated Journal Eur. Phys. J. C
Volume 84 Issue 7 Pages 676 - 27pp
Keywords
Abstract To date, the four-gluon vertex is the least explored component of the QCD Lagrangian, mainly due to the vast proliferation of Lorentz and color structures required for its description. In this work we present a nonperturbative study of this vertex, based on the one-loop dressed Schwinger-Dyson equation obtained from the 4PI effective action. A vast simplification is brought about by resorting to “collinear” kinematics, where all momenta are parallel to each other, and by appealing to the charge conjugation symmetry in order to eliminate certain color structures. Out of the fifteen form factors that comprise the transversely-projected version of this vertex, two are singled out and studied in detail; the one associated with the classical tensorial structure is moderately suppressed in the infrared regime, while the other diverges logarithmically at the origin. Quite interestingly, both form factors display the property known as “planar degeneracy” at a rather high level of accuracy. With these results we construct an effective charge that quantifies the strength of the four-gluon interaction, and compare it with other vertex-derived charges from the gauge sector of QCD.
Address [Aguilar, A. C.; Santos, L. R.] Univ Campinas UNICAMP, Inst Phys Gleb Wataghin, BR-13083859 Campinas, SP, Brazil, Email: aguilar@ifi.unicamp.br
Corporate Author Thesis
Publisher (down) 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:001264786100001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 6199
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Author Centelles Chulia, S.; Herrero-Brocal, A.; Vicente, A.
Title The Type-I Seesaw family Type Journal Article
Year 2024 Publication Journal of High Energy Physics Abbreviated Journal J. High Energy Phys.
Volume 07 Issue 7 Pages 060 - 35pp
Keywords Lepton Flavour Violation (charged); New Light Particles; Non-Standard Neutrino Properties; Specific BSM Phenomenology
Abstract We provide a comprehensive analysis of the Type-I Seesaw family of neutrino mass models, including the conventional type-I seesaw and its low-scale variants, namely the linear and inverse seesaws. We establish that all these models essentially correspond to a particular form of the type-I seesaw in the context of explicit lepton number violation. We then focus into the more interesting scenario of spontaneous lepton number violation, systematically categorizing all inequivalent minimal models. Furthermore, we identify and flesh out specific models that feature a rich majoron phenomenology and discuss some scenarios which, despite having heavy mediators and being invisible in processes such as μ-> e gamma, predict sizable rates for decays including the majoron in the final state.
Address [Centelles Chulia, Salvador] Max Planck Inst Kernphys, Saupfercheckweg 1, D-69117 Heidelberg, Germany, Email: chulia@mpi-hd.mpg.de;
Corporate Author Thesis
Publisher (down) Springer Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1029-8479 ISBN Medium
Area Expedition Conference
Notes WOS:001264784900001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 6201
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Author ATLAS Collaboration (Aad, G. et al); Amos, K.R.; Aparisi Pozo, J.A.; Bailey, A.J.; Bouchhar, N.; Cabrera Urban, S.; Cantero, J.; Cardillo, F.; Castillo Gimenez, V.; Chitishvili, M.; Costa, M.J.; Didenko, M.; Escobar, C.; Fiorini, L.; Fullana Torregrosa, E.; Fuster, J.; Garcia, C.; Garcia Navarro, J.E.; Gomez Delegido, A.J.; Gonzalez de la Hoz, S.; Gonzalvo Rodriguez, G.R.; Guerrero Rojas, J.G.R.; Lacasta, C.; Marti-Garcia, S.; Martinez Agullo, P.; Miralles Lopez, M.; Mitsou, V.A.; Monsonis Romero, L.; Moreno Llacer, M.; Munoz Perez, D.; Navarro-Gonzalez, J.; Poveda, J.; Prades Ibañez, A.; Rubio Jimenez, A.; Ruiz-Martinez, A.; Sabatini, P.; Salt, J.; Sanchez Sebastian, V.; Sayago Galvan, I.; Senthilkumar, V.; Soldevila, U.; Sanchez, J.; Torro Pastor, E.; Valero, A.; Valls Ferrer, J.A.; Varriale, L.; Villaplana Perez, M.; Vos, M.
Title Search for pair production of third-generation leptoquarks decaying into a bottom quark and a τ-lepton with the ATLAS detector Type Journal Article
Year 2023 Publication European Physical Journal C Abbreviated Journal Eur. Phys. J. C
Volume 83 Issue 11 Pages 1075 - 35pp
Keywords
Abstract A search for pair-produced scalar or vector leptoquarks decaying into a b-quark and a tau-lepton is presented using the full LHC Run 2 (2015-2018) data sample of 139 fb(-1) collected with the ATLAS detector in proton-proton collisions at a centre-of-mass energy of root s = 13TeV. Events in which at least one tau-lepton decays hadronically are considered, and multivariate discriminants are used to extract the signals. No significant deviations from the Standard Model expectation are observed and 95% confidence-level upper limits on the production cross-section are derived as a function of leptoquark mass and branching ratio B into a tau-lepton and b-quark. For scalar leptoquarks, masses below 1460GeV are excluded assuming B = 100%, while for vector leptoquarks the corresponding limit is 1650GeV (1910GeV) in the minimal-coupling (Yang-Mills) scenario.
Address [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 (down) 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:001257415700001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 6214
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Author Cepedello, R.; Esser, F.; Hirsch, M.; Sanz, V.
Title Fermionic UV models for neutral triple gauge boson vertices Type Journal Article
Year 2024 Publication Journal of High Energy Physics Abbreviated Journal J. High Energy Phys.
Volume 07 Issue 7 Pages 275 - 28pp
Keywords Effective Field Theories; SMEFT; Specific BSM Phenomenology; Vector-Like Fermions
Abstract Searches for anomalous neutral triple gauge boson couplings (NTGCs) provide important tests for the gauge structure of the standard model. In SMEFT (“standard model effective field theory”) NTGCs appear only at the level of dimension-8 operators. While the phenomenology of these operators has been discussed extensively in the literature, renormalizable UV models that can generate these operators are scarce. In this work, we study a variety of extensions of the SM with heavy fermions and calculate their matching to d = 8 NTGC operators. We point out that the complete matching of UV models requires four different CP-conserving d = 8 operators and that the single CPC d = 8 operator, most commonly used by the experimental collaborations, does not describe all possible NTGC form factors. Despite stringent experimental constraints on NTGCs, limits on the scale of UV models are relatively weak, because their contributions are doubly suppressed (being d = 8 and 1-loop). We suggest a series of benchmark UV scenarios suitable for interpreting searches for NTGCs in the upcoming LHC runs, obtain their current limits and provide estimates for the expected sensitivity of the high-luminosity LHC.
Address [Cepedello, Ricardo] Univ Granada, Dept Fis Teor & Cosmos, Campus Fuentenueva, E-18071 Granada, Spain, Email: ricepe@ugr.es;
Corporate Author Thesis
Publisher (down) Springer Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1029-8479 ISBN Medium
Area Expedition Conference
Notes WOS:001282227200003 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 6222
Permanent link to this record
 

 
Author Martins, A.; da Mota, A.F.; Stanford, C.; Contreras, T.; Martin-Albo, J.; Kish, A.; Escobar, C.O.; Para, A.; Guenette, R.
Title Simple strategy for the simulation of axially symmetric large-area metasurfaces Type Journal Article
Year 2024 Publication Journal of the Optical Society of America B Abbreviated Journal J. Opt. Soc. Am. B
Volume 41 Issue 5 Pages 1261-1269
Keywords
Abstract Metalenses are composed of nanostructures for focusing light and have been widely explored in many exciting applications. However, their expanding dimensions pose simulation challenges. We propose a method to simulate metalenses in a timely manner using vectorial wave and ray tracing models. We sample the metalens's radial phase gradient and locally approximate the phase profile by a linear phase response. Each sampling point is modeled as a binary blazed grating, employing the chosen nanostructure, to build a transfer function set. The metalens transmission or reflection is then obtained by applying the corresponding transfer function to the incoming field on the regions surrounding each sampling point. Fourier optics is used to calculate the scattered fields under arbitrary illumination for the vectorial wave method, and a Monte Carlo algorithm is used in the ray tracing formalism. We validated our method against finite -difference time domain simulations at 632 nm, and we were able to simulate metalenses larger than 3000 wavelengths in diameter on a personal computer.
Address [Martins, Augusto; Guenette, Roxanne] Univ Manchester, Dept Phys, Manchester M13 9PL, England, Email: augusto.martins@york.ac.uk
Corporate Author Thesis
Publisher (down) Optica Publishing Group Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0740-3224 ISBN Medium
Area Expedition Conference
Notes WOS:001237140900001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 6140
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Author Penas, J.; Alejo, A.; Bembibre, A.; Apiñaniz, J.I.; Garcia-Garcia, E.; Guerrero, C.; Henares, J.L.; Hernandez-Palmero, I.; Mendez, C.; Millan-Callado, M.A.; Puyuelo-Valdes, P.; Seimetz, M.; Benlliure, J.
Title Production of carbon-11 for PET preclinical imaging using a high-repetition rate laser-driven proton source Type Journal Article
Year 2024 Publication Scientific Reports Abbreviated Journal Sci Rep
Volume 14 Issue 1 Pages 11448 - 12pp
Keywords
Abstract Most advanced medical imaging techniques, such as positron-emission tomography (PET), require tracers that are produced in conventional particle accelerators. This paper focuses on the evaluation of a potential alternative technology based on laser-driven ion acceleration for the production of radioisotopes for PET imaging. We report for the first time the use of a high-repetition rate, ultra-intense laser system for the production of carbon-11 in multi-shot operation. Proton bunches with energies up to 10-14 MeV were systematically accelerated in long series at pulse rates between 0.1 and 1 Hz using a PW-class laser. These protons were used to activate a boron target via the 11 \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$<^>{11}$$\end{document} B(p,n) 11 \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$<^>{11}$$\end{document} C nuclear reaction. A peak activity of 234 kBq was obtained in multi-shot operation with laser pulses with an energy of 25 J. Significant carbon-11 production was also achieved for lower pulse energies. The experimental carbon-11 activities measured in this work are comparable to the levels required for preclinical PET, which would be feasible by operating at the repetition rate of current state-of-the-art technology (10 Hz). The scalability of next-generation laser-driven accelerators in terms of this parameter for sustained operation over time could increase these overall levels into the clinical PET range.
Address [Penas, Juan; Alejo, Aaron; Bembibre, Adrian; Benlliure, Jose] Univ Santiago de Compostela, Inst Galego Fis Altas Enerxias IGFAE, Santiago De Compostela 15782, Spain, Email: j.benlliure@usc.es
Corporate Author Thesis
Publisher (down) Nature Portfolio Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2045-2322 ISBN Medium
Area Expedition Conference
Notes WOS:001228252900017 Approved no
Is ISI yes International Collaboration no
Call Number IFIC @ pastor @ Serial 6143
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Author Di Gregorio, E.; Staelens, M.; Hosseinkhah, N.; Karimpoor, M.; Liburd, J.; Lim, L.; Shankar, K.; Tuszynski, J.A.
Title Raman Spectroscopy Reveals Photobiomodulation-Induced α-Helix to β-Sheet Transition in Tubulins: Potential Implications for Alzheimer's and Other Neurodegenerative Diseases Type Journal Article
Year 2024 Publication Nanomaterials Abbreviated Journal Nanomaterials
Volume 14 Issue 13 Pages 1093 - 21pp
Keywords proteins; protein dynamics; protein structure; non-invasive therapies; low-level laser therapy; spectroscopy; amide bands; amide I; spectral decomposition
Abstract In small clinical studies, the application of transcranial photobiomodulation (PBM), which typically delivers low-intensity near-infrared (NIR) to treat the brain, has led to some remarkable results in the treatment of dementia and several neurodegenerative diseases. However, despite the extensive literature detailing the mechanisms of action underlying PBM outcomes, the specific mechanisms affecting neurodegenerative diseases are not entirely clear. While large clinical trials are warranted to validate these findings, evidence of the mechanisms can explain and thus provide credible support for PBM as a potential treatment for these diseases. Tubulin and its polymerized state of microtubules have been known to play important roles in the pathology of Alzheimer's and other neurodegenerative diseases. Thus, we investigated the effects of PBM on these cellular structures in the quest for insights into the underlying therapeutic mechanisms. In this study, we employed a Raman spectroscopic analysis of the amide I band of polymerized samples of tubulin exposed to pulsed low-intensity NIR radiation (810 nm, 10 Hz, 22.5 J/cm2 dose). Peaks in the Raman fingerprint region (300-1900 cm-1)-in particular, in the amide I band (1600-1700 cm-1)-were used to quantify the percentage of protein secondary structures. Under this band, hidden signals of C=O stretching, belonging to different structures, are superimposed, producing a complex signal as a result. An accurate decomposition of the amide I band is therefore required for the reliable analysis of the conformation of proteins, which we achieved through a straightforward method employing a Voigt profile. This approach was validated through secondary structure analyses of unexposed control samples, for which comparisons with other values available in the literature could be conducted. Subsequently, using this validated method, we present novel findings of statistically significant alterations in the secondary structures of polymerized NIR-exposed tubulin, characterized by a notable decrease in alpha-helix content and a concurrent increase in beta-sheets compared to the control samples. This PBM-induced alpha-helix to beta-sheet transition connects to reduced microtubule stability and the introduction of dynamism to allow for the remodeling and, consequently, refreshing of microtubule structures. This newly discovered mechanism could have implications for reducing the risks associated with brain aging, including neurodegenerative diseases like Alzheimer's disease, through the introduction of an intervention following this transition.
Address [Di Gregorio, Elisabetta; Staelens, Michael; Tuszynski, Jack A.] Univ Alberta, Fac Sci, Dept Phys, Edmonton, AB T6G 2E1, Canada, Email: michael.staelens@ific.uv.es
Corporate Author Thesis
Publisher (down) Mdpi Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN ISBN Medium
Area Expedition Conference
Notes WOS:001269841000001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 6204
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Author Maluf, R.V.; Mora-Perez, G.; Olmo, G.J.; Rubiera-Garcia, D.
Title Nonsingular, Lump-like, Scalar Compact Objects in (2+1)-Dimensional Einstein Gravity Type Journal Article
Year 2024 Publication Universe Abbreviated Journal Universe
Volume 10 Issue 6 Pages 258 - 13pp
Keywords Einstein gravity; compact objects; nonlinear scalar field
Abstract We study the space-time geometry generated by coupling a free scalar field with a noncanonical kinetic term to general relativity in (2+1) dimensions. After identifying a family of scalar Lagrangians that yield exact analytical solutions in static and circularly symmetric scenarios, we classify the various types of solutions and focus on a branch that yields asymptotically flat geometries. We show that the solutions within such a branch can be divided in two types, namely naked singularities and nonsingular objects without a center. In the latter, the energy density is localized around a maximum and vanishes only at infinity and at an inner boundary. This boundary has vanishing curvatures and cannot be reached by any time-like or null geodesic in finite affine time. This allows us to consistently interpret such solutions as nonsingular, lump-like, static compact scalar objects whose eventual extension to the (3+1)-dimensional context could provide structures of astrophysical interest.
Address [Maluf, Roberto V.; Olmo, Gonzalo J.] Univ Fed Ceara UFC, Dept Fis, Campus Pici, BR-60455760 Fortaleza, Ceara, Brazil, Email: r.v.maluf@fisica.ufc.br;
Corporate Author Thesis
Publisher (down) Mdpi Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN ISBN Medium
Area Expedition Conference
Notes WOS:001256495600001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 6169
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Author Figueroa, D.G.; Florio, A.; Torrenti, F.
Title Present and future of Cosmo Lattice Type Journal Article
Year 2024 Publication Reports on Progress in Physics Abbreviated Journal Rep. Prog. Phys.
Volume 87 Issue 9 Pages 094901 - 20pp
Keywords early Universe; non-linear dynamics; real-time lattice simulations; cosmology; gauge-invariant lattice techniques; CosmoLattice; gravitational waves
Abstract We discuss the present state and planned updates of Cosmo Lattice, a cutting-edge code for lattice simulations of non-linear dynamics of scalar-gauge field theories in an expanding background. We first review the current capabilities of the code, including the simulation of interacting singlet scalars and of Abelian and non-Abelian scalar-gauge theories. We also comment on new features recently implemented, such as the simulation of gravitational waves from scalar and gauge fields. Secondly, we discuss new extensions of C osmo L attice that we plan to release publicly. We comment on new physics modules, which include axion-gauge interactions phi FF , non-minimal gravitational couplings phi R-2 , creation and evolution of cosmic-defect networks, and magnetohydrodynamics. We also discuss new technical features, including evolvers for non-canonical interactions, arbitrary initial conditions, simulations in 2+1 dimensions, and higher-accuracy spatial derivatives.
Address [Figueroa, Daniel G.; Torrenti, Francisco] CSIC, Inst Fis Corpuscular IFIC, Valencia 46980, Spain, Email: daniel.figueroa@ific.uv.es;
Corporate Author Thesis
Publisher (down) 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 0034-4885 ISBN Medium
Area Expedition Conference
Notes WOS:001284570700001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 6219
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Author Mata, R.; Cros, A.; Gimeno, B.; Raboso, D.
Title Secondary electron emission yield in thick dielectric materials: a comparison between Kelvin probe and capacitive methods Type Journal Article
Year 2024 Publication Journal of Physics D Abbreviated Journal J. Phys. D
Volume 57 Issue 40 Pages 405302 - 9pp
Keywords dielectrics; secondary electron emission yield; Multipactor in space devices
Abstract The recent high demand of secondary electron emission yield (SEY) measurements in dielectric materials from space industry has driven SEY laboratories to improve their facilities and measurement techniques. SEY determination by the common capacitive method, also known as pulsed method, is well accepted and has given satisfactory results in most cases. Nevertheless, the samples under study must be prepared according to the experimental limitations of the technique, i.e. they should be manufactured separated from the devices representing faithfully the surface state of the own device and be as thin as possible. A method based on the Kelvin probe (KP) is proposed here to obtain the SEY characteristics of electrically floating Platinum, Kapton and Teflon placed over dielectric spacers with thicknesses ranging from 1.6 to 12.1 mm. The results are compared with those of the capacitive method and indicate that KP SEY curves are less sensitive to spacer thickness. An explanation based on the literature is also given. In all, we have established that KP is better suited for the analysis of dielectric samples thicker than 3 mm.
Address [Mata, R.; Gimeno, B.] Ciudad Politecn Innovac, Val Space Consortium, Edificio 8G,Acceso B,Planta B, Valencia 46022, Spain, Email: rafael.mata@uv.es
Corporate Author Thesis
Publisher (down) 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 0022-3727 ISBN Medium
Area Expedition Conference
Notes WOS:001269188200001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 6203
Permanent link to this record