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Author Guadilla, V.; Algora, A.; Estienne, M.; Fallot, M.; Gelletly, W.; Porta, A.; Rigalleau, L.M.; Stutzmann, J.S.
Title First measurements with a new fl-electron detector for spectral shape studies Type Journal Article
Year 2024 Publication Journal of Instrumentation Abbreviated Journal J. Instrum.
Volume 19 Issue 2 Pages P02027 - 21pp
Keywords Detector modelling and simulations I (interaction of radiation with matter; interaction of photons with matter; interaction of hadrons with matter; etc); Instrumentation for radioactive beams (fragmentation devices; fragment and isotope; separators incl. ISOL; isobar separators; ion and atom traps; weak-beam diagnostics; radioactive-beam ion sources); Hybrid detectors; Spectrometers
Abstract The shape of the electron spectrum emitted in /3 decay carries a wealth of information about nuclear structure and fundamental physics. In spite of that, few dedicated measurements have been made of /3 -spectrum shapes. In this work we present a newly developed detector for /3 electrons based on a telescope concept. A thick plastic scintillator is employed in coincidence with a thin silicon detector. The first measurements employing this detector have been carried out with mono -energetic electrons from the high-energy resolution electron -beam spectrometer at Bordeaux. Here we report on the good reproduction of the experimental spectra of mono -energetic electrons using Monte Carlo simulations. This is a crucial step for future experiments, where a detailed Monte Carlo characterization of the detector is needed to determine the shape of the /3 -electron spectra by deconvolution of the measured spectra with the response function of the detector. A chamber to contain two telescope assemblies has been designed for future /3 -decay experiments at the Ion Guide Isotope Separator On -Line facility in Jyvaskyla, aimed at improving our understanding of reactor antineutrino spectra.
Address [Guadilla, V.; Estienne, M.; Fallot, M.; Porta, A.; Rigalleau, L. -m.; Stutzmann, J. -s.] Univ Nantes, Subatech, IMT Atlantique, CNRS,IN2P3, F-44307 Nantes, France, Email: vguadilla@fuw.edu.pl
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 (down) WOS:001181748300007 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 6064
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Author Alexandre, J.; Mavromatos, N.E.; Mitsou, V.A.; Musumeci, E.
Title Resummation schemes for high-electric-charge objects leading to improved experimental mass limits Type Journal Article
Year 2024 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 109 Issue 3 Pages 036026 - 20pp
Keywords
Abstract High-electric-charge compact objects (HECOs) appear in several theoretical particle physics models beyond the Standard Model, and are actively searched for in current colliders, such as the Large Hadron Collider at CERN. In such searches, mass bounds of these objects have been placed, using Drell-Yan and photon-fusion processes at tree level so far. However, such mass-bound estimates are not reliable, given that, as a result of the large values of the electric charge of the HECO, perturbative quantum electrodynamics calculations break down. In this work, we perform a Dyson-Schwinger resummation scheme (as opposed to lattice strong-coupling approach), which makes the computation of the pertinent HECO-production cross sections reliable, thus allowing us to extract improved mass bounds for such objects from ATLAS and MoEDAL searches.
Address [Alexandre, Jean; Mavromatos, Nick E.] Kings Coll London, Dept Phys, Theoret Particle Phys & Cosmol Grp, London WC2R 2LS, England, Email: jean.alexandre@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 (down) WOS:001181678500003 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 5995
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Author Fajfer, S.; Solomonidi, E.; Vale Silva, L.
Title S-wave contribution to rare D0 → π+ π- l+ l- decays in the standard model and sensitivity to new physics Type Journal Article
Year 2024 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 109 Issue 3 Pages 036027 - 24pp
Keywords
Abstract Physics of the up-type flavor offers unique possibilities of testing the standard model (SM) compared to the down-type flavor sector. Here, we discuss SM and new physics (NP) contributions to the rare charmmeson decay D0 -> x+x- l+l-. In particular, we discuss the effect of including the lightest scalar isoscalar resonance in the SM picture, namely, the f0(500), which manifests in a big portion of the allowed phase space. Other than showing in the total branching ratio at an observable level of about 20%, the f0(500) resonance manifests as interference terms with the vector resonances, such as at high invariant mass of the leptonic pair in distinct angular observables. Recent data from LHCb optimize the sensitivity to P-wave contributions that we analyze in view of the inclusion of vector resonances. We propose the measurement of alternative observables that are sensitive to the S-wave and are straightforward to implement experimentally. This leads to a new set of null observables that vanish in the SM due to its gauge and flavor structures. Finally, we study observables that depend on the SM interference with generic NP contributions from semileptonic four-fermion operators in the presence of the S-wave.
Address [Fajfer, Svjetlana] Jozef Stefan Inst, Jamova 39,POB 3000, Ljubljana 1001, Slovenia
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 (down) WOS:001181678500001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 5991
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Author Ferreiro, A.; Monin, S.; Torrenti, F.
Title Physical scale adiabatic regularization in cosmological spacetimes Type Journal Article
Year 2024 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 109 Issue 4 Pages 045015 - 16pp
Keywords
Abstract We develop a new regularization method for the stress -energy tensor and the two -point function of free quantum scalar fields propagating in cosmological spacetimes. We proceed by extending the adiabatic regularization scheme with the introduction of two additional mass scales. By setting them to the order of the physical scale of the studied scenario, we obtain ultraviolet -regularized quantities that do not distort the power spectra amplitude at the infrared scales amplified by the expansion of the Universe. This is not ensured by the standard adiabatic approach. We also show how our proposed subtraction terms can be interpreted as a renormalization of coupling constants in the Einstein equations. We finally illustrate our proposed regularization method in two scenarios of cosmological interest: de Sitter inflation and geometric reheating.
Address [Ferreiro, Antonio] Univ Utrecht, Freudenthal Inst, NL-3584CC Utrecht, Netherlands, Email: antonio.ferreiro@ru.nl;
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 (down) WOS:001180335500003 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 6015
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Author Bordes, J.; Chan, H.M.; Tsou, S.T.
Title Search for new physics in semileptonic decays of K and B as implied by the g-2 anomaly in FSM Type Journal Article
Year 2023 Publication International Journal of Modern Physics A Abbreviated Journal Int. J. Mod. Phys. A
Volume 38 Issue Pages 2350177 - 24pp
Keywords Framed standard model; light scalar boson; meson decays
Abstract The framed standard model (FSM), constructed to explain, with some success, why there should be three and apparently only three generations of quarks and leptons in nature falling into a hierarchical mass and mixing pattern,(10) suggests also, among other things, a scalar boson U, with mass around 17 MeV and small couplings to quarks and leptons,(11) which might explain(9) the g – 2 anomaly reported in experiment.(12) The U arises in FSM initially as a state in the predicted “hidden sector” with mass around 17 MeV, which mixes with the standard model (SM) Higgs h(W), acquiring thereby a coupling to quarks and leptons and a mass just below 17 MeV. The initial purpose of this paper is to check whether this proposal is compatible with experiment on semileptonic decays of Ks and Bs where the U can also appear. The answer to this we find is affirmative, in that the contribution of U to new physics as calculated in the FSM remains within the experimental bounds, but only if m(U) lies within a narrow range just below the unmixed mass. As a result from this, one has an estimate m(U) similar to 15-17 MeV for the mass of U, and from some further considerations the estimate Gamma(U) similar to 0.02 eV for its width, both of which may be useful for an eventual search for it in experiment. If found, it will be, for the FSM, not just the discovery of a predicted new particle, but the opening of a window into a whole “hidden sector” containing at least some, perhaps even the bulk, of the dark matter in the universe.
Address [Bordes, Jose] Univ Valencia, Ctr Mixto CSIC, Dept Fis Teor, Calle Dr Moliner 50, E-46100 Burjassot, Valencia, Spain, Email: jose.m.bordes@uv.es;
Corporate Author Thesis
Publisher World Scientific Publ Co Pte Ltd Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0217-751x ISBN Medium
Area Expedition Conference
Notes (down) WOS:001180240500002 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 5978
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