|   | 
Details
   web
Records
Author (up) Banerjee, P.; Coutinho, A.; Engel, T.; Gurgone, A.; Signer, A.; Ulrich, Y.
Title High-precision muon decay predictions for ALP searches Type Journal Article
Year 2023 Publication Scipost Physics Abbreviated Journal SciPost Phys.
Volume 15 Issue 1 Pages 021 - 38pp
Keywords
Abstract We present an improved theoretical prediction of the positron energy spectrum for the polarised Michel decay & mu;+ & RARR; e+ & nu;e & nu; over bar & mu;. In addition to the full next-to-next-to-leading order correction of order & alpha;2 in the electromagnetic coupling, we include logarithmically enhanced terms at even higher orders. Logarithms due to collinear emission are included at next-to-leading accuracy up to order & alpha;4. At the endpoint of the Michel spectrum, soft photon emission results in large logarithms that are resummed up to next-to-next-to leading logarithmic accuracy. We apply our results in the context of the MEG II and Mu3e experiments to estimate the impact of the theory error on the branching ratio sensitivity for the lepton-flavour-violating decay & mu;+ & RARR; e+X of a muon into an axion-like particle X.
Address [Banerjee, Pulak] Zhejiang Univ, Zhejiang Inst Modern Phys, Dept Phys, Hangzhou 310027, Peoples R China
Corporate Author Thesis
Publisher Scipost Foundation Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2542-4653 ISBN Medium
Area Expedition Conference
Notes WOS:001038392400002 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 5595
Permanent link to this record
 

 
Author (up) Botella, F.J.; Branco, G.C.; Coutinho, A.M.; Rebelo, M.N.; Silva-Marcos, J.I.
Title Natural quasi-alignment with two Higgs doublets and RGE stability Type Journal Article
Year 2015 Publication European Physical Journal C Abbreviated Journal Eur. Phys. J. C
Volume 75 Issue 6 Pages 286 - 9pp
Keywords
Abstract In the context of two Higgs doublet models, we study the conditions required in order to have stable quasi-alignment in flavour space. We show that stability under the renormalisation group equations imposes strong constraints on the flavour structure of the Yukawa couplings associated to each one of the Higgs doublets. In particular, we find a novel solution, where all Yukawa couplings are proportional to the so-called democratic matrix. This solution is rather unique, since it is the only stable solution which is a good starting point for reproducing the observed pattern of quark masses and mixing. We also showthat this stable solution can be obtained by imposing on the Lagrangian a Z(3)xZ(3)' flavour symmetry. Quark masses of the lighter quark generations are generated through the breaking of this discrete symmetry, and, at this stage, scalar-mediated flavour-changing neutralcurrents arise, but they are naturally suppressed by the smallness of the light quark masses. In this way, we relate Higgs alignment to the hierarchy of the quark masses through a discrete family symmetry.
Address [Botella, F. J.] Univ Valencia, Dept Fis Teor, CSIC, E-46100 Burjassot, Spain, Email: fbotella@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:000356888300003 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 2299
Permanent link to this record
 

 
Author (up) de Blas, J.; Chowdhury, D.; Ciuchini, M.; Coutinho, A.M.; Eberhardt, O.; Fedele, M.; Franco, E.; di Cortona, G.G.; Miralles, V.; Mishima, S.; Paul, A.; Peñuelas, A.; Pierini, M.; Reina, L.; Silvestrini, L.; Valli, M.; Watanabe, R.; Yokozaki, N.
Title HEPfit: a code for the combination of indirect and direct constraints on high energy physics models Type Journal Article
Year 2020 Publication European Physical Journal C Abbreviated Journal Eur. Phys. J. C
Volume 80 Issue 5 Pages 456 - 31pp
Keywords
Abstract HEPfit is a flexible open-source tool which, given the Standard Model or any of its extensions, allows to (i) fit the model parameters to a given set of experimental observables; (ii) obtain predictions for observables. HEPfit can be used either in Monte Carlo mode, to perform a Bayesian Markov Chain Monte Carlo analysis of a given model, or as a library, to obtain predictions of observables for a given point in the parameter space of the model, allowing HEPfit to be used in any statistical framework. In the present version, around a thousand observables have been implemented in the Standard Model and in several new physics scenarios. In this paper, we describe the general structure of the code as well as models and observables implemented in the current release.
Address [de Blas, J.] Univ Padua, Dipartimento Fis & Astron Galileo Galilei, Via Marzolo 8, I-35131 Padua, Italy, Email: hepfit-support@romal.infn.it
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:000537056900002 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 4414
Permanent link to this record