Records |
Author |
Blennow, M.; Fernandez-Martinez, E.; Hernandez-Garcia, J.; Lopez-Pavon, J.; Marcano, X.; Naredo-Tuero, D. |
Title ![sorted by Title field, ascending order (up)](img/sort_asc.gif) |
Bounds on lepton non-unitarity and heavy neutrino mixing |
Type |
Journal Article |
Year |
2023 |
Publication |
Journal of High Energy Physics |
Abbreviated Journal |
J. High Energy Phys. |
Volume |
08 |
Issue |
8 |
Pages |
030 - 41pp |
Keywords |
Electroweak Precision Physics; Neutrino Mixing; Sterile or Heavy Neutrinos |
Abstract |
We present an updated and improved global fit analysis of current flavour and electroweak precision observables to derive bounds on unitarity deviations of the leptonic mixing matrix and on the mixing of heavy neutrinos with the active flavours. This new analysis is motivated by new and updated experimental results on key observables such as V-ud, the invisible decay width of the Z boson and the W boson mass. It also improves upon previous studies by considering the full correlations among the different observables and explicitly calibrating the test statistic, which may present significant deviations from a & chi;(2) distribution. The results are provided for three different Type-I seesaw scenarios: the minimal scenario with only two additional right-handed neutrinos, the next to minimal one with three extra neutrinos, and the most general one with an arbitrary number of heavy neutrinos that we parametrise via a generic deviation from a unitary leptonic mixing matrix. Additionally, we also analyze the case of generic deviations from unitarity of the leptonic mixing matrix, not necessarily induced by the presence of additional neutrinos. This last case relaxes some correlations among the parameters and is able to provide a better fit to the data. Nevertheless, inducing only leptonic unitarity deviations avoiding both the correlations implied by the right-handed neutrino extension as well as more strongly constrained operators is challenging and would imply significantly more complex UV completions. |
Address |
[Blennow, Mattias] KTH Royal Inst Technol, AlbaNova Univ Ctr, Sch Engn Sci, Dept Phys, Roslagstullsbacken 21, S-10691 Stockholm, Sweden, Email: emb@kth.se; |
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Thesis |
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Publisher |
Springer |
Place of Publication |
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Editor |
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Language |
English |
Summary Language |
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Original Title |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1029-8479 |
ISBN |
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Medium |
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Area |
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Expedition |
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Conference |
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Notes |
WOS:001044930400003 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
5607 |
Permanent link to this record |
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Author |
Coloma, P.; Esteban, I.; Gonzalez-Garcia, M.C.; Larizgoitia, L.; Monrabal, F.; Palomares-Ruiz, S. |
Title ![sorted by Title field, ascending order (up)](img/sort_asc.gif) |
Bounds on new physics with data of the Dresden-II reactor experiment and COHERENT |
Type |
Journal Article |
Year |
2022 |
Publication |
Journal of High Energy Physics |
Abbreviated Journal |
J. High Energy Phys. |
Volume |
05 |
Issue |
5 |
Pages |
037 - 33pp |
Keywords |
Neutrino Interactions; Non-Standard Neutrino Properties; New Light Particles |
Abstract |
Coherent elastic neutrino-nucleus scattering was first experimentally established five years ago by the COHERENT experiment using neutrinos from the spallation neutron source at Oak Ridge National Laboratory. The first evidence of observation of coherent elastic neutrino-nucleus scattering with reactor antineutrinos has now been reported by the Dresden-II reactor experiment, using a germanium detector. In this paper, we present constraints on a variety of beyond the Standard Model scenarios using the new Dresden-II data. In particular, we explore the constraints imposed on neutrino nonstandard interactions, neutrino magnetic moments, and several models with light scalar or light vector mediators. We also quantify the impact of their combination with COHERENT (CsI and Ar) data. In doing so, we highlight the synergies between spallation neutron source and nuclear reactor experiments regarding beyond the Standard Model searches, as well as the advantages of combining data obtained with different nuclear targets. We also study the possible signal from beyond the Standard Model scenarios due to elastic scattering off electrons (which would pass selection cuts of the COHERENT CsI and the Dresden-II experiments) and find more stringent constraints in certain parts of the parameter space than those obtained considering coherent elastic neutrino-nucleus scattering. |
Address |
[Coloma, Pilar] Univ Autonoma Madrid, Inst Fis Teor UAM CSIC, Calle Nicolas Cabrera 18-15, E-28049 Madrid, Spain, Email: pilar.coloma@ift.csic.es; |
Corporate Author |
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Thesis |
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Publisher |
Springer |
Place of Publication |
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Editor |
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Language |
English |
Summary Language |
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Original Title |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1029-8479 |
ISBN |
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Medium |
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Area |
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Expedition |
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Conference |
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Notes |
WOS:000791925200002 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
5222 |
Permanent link to this record |
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Author |
Hernandez, P.; Lopez-Pavon, J.; Rius, N.; Sandner, S. |
Title ![sorted by Title field, ascending order (up)](img/sort_asc.gif) |
Bounds on right-handed neutrino parameters from observable leptogenesis |
Type |
Journal Article |
Year |
2022 |
Publication |
Journal of High Energy Physics |
Abbreviated Journal |
J. High Energy Phys. |
Volume |
12 |
Issue |
12 |
Pages |
012 - 58pp |
Keywords |
Baryo-and Leptogenesis; Early Universe Particle Physics; Sterile or Heavy Neutrinos |
Abstract |
We revisit the generation of a matter-antimatter asymmetry in the minimal extension of the Standard Model with two singlet heavy neutral leptons (HNL) that can explain neutrino masses. We derive an accurate analytical approximation to the solution of the complete linearized set of kinetic equations, which exposes the non-trivial parameter dependencies in the form of parameterization-independent CP invariants. The identification of various washout regimes relevant in different regions of parameter space sheds light on the relevance of the mass corrections in the interaction rates and clarifies the correlations of baryogenesis with other observables. In particular, by requiring that the measured baryon asymmetry is reproduced, we derive robust upper or lower bounds on the HNL mixings depending on their masses, and constraints on their flavour structure, as well as on the CP-violating phases of the PMNS mixing matrix, and the amplitude of neutrinoless double-beta decay. We also find certain correlations between low and high scale CP phases. Especially emphasizing the testable part of the parameter space we demonstrate that our findings are in very good agreement with numerical results. The methods developed in this work can help in exploring more complex scenarios. |
Address |
[Hernandez, P.] Univ Valencia, Inst Fis Corpuscular, Edificio Inst Invest,Catedrat Jose Beltran 2, Paterna 46980, Spain, Email: m.pilar.hernandez@uv.es; |
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Publisher |
Springer |
Place of Publication |
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Editor |
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Language |
English |
Summary Language |
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Original Title |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1029-8479 |
ISBN |
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Medium |
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Area |
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Expedition |
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Conference |
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Notes |
WOS:000914640400003 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
no |
Call Number |
IFIC @ pastor @ |
Serial |
5467 |
Permanent link to this record |
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Author |
Li, X.Q.; Lu, J.; Pich, A. |
Title ![sorted by Title field, ascending order (up)](img/sort_asc.gif) |
Bs,d(0) -> l(+)l(-) decays in the aligned two-Higgs-doublet model |
Type |
Journal Article |
Year |
2014 |
Publication |
Journal of High Energy Physics |
Abbreviated Journal |
J. High Energy Phys. |
Volume |
06 |
Issue |
6 |
Pages |
022 - 39pp |
Keywords |
Higgs Physics; Rare Decays; Beyond Standard Model; B-Physics |
Abstract |
The rare decays B-s,d(0) -> l(+)l(-) are analyzed within the general framework of the aligned two-Higgs doublet model. We present a complete one-loop calculation of the relevant short-distance Wilson coefficients, giving a detailed technical summary of our results and comparing them with previous calculations performed in particular limits or approximations. We investigate the impact of various model parameters on the branching ratios and study the phenomenological constraints imposed by present data. |
Address |
[Li, Xin-Qiang] Cent China Normal Univ, Inst Particle Phys, Wuhan 430079, Hubei, Peoples R China, Email: xqli@itp.ac.cn; |
Corporate Author |
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Thesis |
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Publisher |
Springer |
Place of Publication |
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Editor |
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Language |
English |
Summary Language |
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Original Title |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1029-8479 |
ISBN |
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Medium |
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Area |
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Expedition |
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Conference |
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Notes |
WOS:000338520600002 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
1855 |
Permanent link to this record |
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Author |
Aguilera-Verdugo, J.J.; Hernandez-Pinto, R.J.; Rodrigo, G.; Sborlini, G.F.R.; Torres Bobadilla, W.J. |
Title ![sorted by Title field, ascending order (up)](img/sort_asc.gif) |
Causal representation of multi-loop Feynman integrands within the loop-tree duality |
Type |
Journal Article |
Year |
2021 |
Publication |
Journal of High Energy Physics |
Abbreviated Journal |
J. High Energy Phys. |
Volume |
01 |
Issue |
1 |
Pages |
69 - 26pp |
Keywords |
Duality in Gauge Field Theories; Perturbative QCD; Scattering Amplitudes |
Abstract |
The numerical evaluation of multi-loop scattering amplitudes in the Feynman representation usually requires to deal with both physical (causal) and unphysical (non-causal) singularities. The loop-tree duality (LTD) offers a powerful framework to easily characterise and distinguish these two types of singularities, and then simplify analytically the underling expressions. In this paper, we work explicitly on the dual representation of multi-loop Feynman integrals generated from three parent topologies, which we refer to as Maximal, Next-to-Maximal and Next-to-Next-to-Maximal loop topologies. In particular, we aim at expressing these dual contributions, independently of the number of loops and internal configurations, in terms of causal propagators only. Thus, providing very compact and causal integrand representations to all orders. In order to do so, we reconstruct their analytic expressions from numerical evaluation over finite fields. This procedure implicitly cancels out all unphysical singularities. We also interpret the result in terms of entangled causal thresholds. In view of the simple structure of the dual expressions, we integrate them numerically up to four loops in integer space-time dimensions, taking advantage of their smooth behaviour at integrand level. |
Address |
[Jesus Aguilera-Verdugo, J.; Rodrigo, German; Sborlini, German F. R.; Torres Bobadilla, William J.] Univ Valencia, Inst Fis Corpuscular, CSIC, Parc Cientif, E-46980 Valencia, Spain, Email: jesus.aguilera@ific.uv.es; |
Corporate Author |
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Thesis |
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Publisher |
Springer |
Place of Publication |
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Editor |
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Language |
English |
Summary Language |
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Original Title |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1029-8479 |
ISBN |
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Medium |
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Area |
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Expedition |
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Conference |
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Notes |
WOS:000609437600001 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
4697 |
Permanent link to this record |