|   | 
Details
   web
Records
Author Gomez Dumm, D.; Roig, P.; Pich, A.; Portoles, J.
Title Hadron structure in tau -> KK pi nu(tau) decays Type Journal Article
Year 2010 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume (down) 81 Issue 3 Pages 034031 - 17pp
Keywords
Abstract We analyze the hadronization structure of both vector and axial-vector currents leading to tau -> KK pi nu(tau) decays. At leading order in the 1/N-C expansion, and considering only the contribution of the lightest resonances, we work out, within the framework of the resonance chiral Lagrangian, the structure of the local vertices involved in those processes. The couplings in the resonance theory are constrained by imposing the asymptotic behavior of vector and axial-vector spectral functions ruled by QCD. In this way we predict the hadron spectra and conclude that, contrary to previous assertions, the vector contribution dominates by far over the axial-vector one in all KK pi charge channels.
Address [Gomez Dumm, D.] Univ Nacl La Plata, IFLP, CONICET, Dpto Fis, RA-1900 La Plata, Argentina
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 1550-7998 ISBN Medium
Area Expedition Conference
Notes ISI:000275069000052 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ elepoucu @ Serial 496
Permanent link to this record
 

 
Author Flores-Tlalpa, A.; Lopez Castro, G.; Roig, P.
Title Five-body leptonic decays of muon and tau lepton Type Journal Article
Year 2016 Publication Journal of High Energy Physics Abbreviated Journal J. High Energy Phys.
Volume (down) 04 Issue 4 Pages 185 - 21pp
Keywords CP violation; Discrete Symmetries; Effective field theories; Precision QED
Abstract We study the five-body decays u(-) -> e(-)e(+)e(-)nu u (nu) over bar (e) and tau(-) -> l(-)l'+l'-nu(tau)(nu) over bar (l) for l, l' = e, u within the Standard Model (SM) and in a general effective field theory description of the weak interactions at low energies. We compute the branching ratios and compare our results with two previous – mutually discrepan – SM calculations. By assuming a general structure for the weak currents we derive the expressions for the energy and angular distributions of the three charged leptons when the decaying lepton is polarized, which will be useful in precise tests of the weak charged current at Belle II. In these decays, leptonic T-odd correlations in triple products of spin and momenta – which may signal time reversal violation in the leptonic sector – are suppressed by the tiny neutrino masses. Therefore, a measurement of such T-violating observables would be associated to neutrinoless lepton flavor violating (LFV) decays, where this effect is not extremely suppressed. We also study the backgrounds that the SM five-lepton lepton decays constitute to searches of LFV L- -> ? l(-)l'+l'(-) decays. Searches at high values of the invariant mass of the l'(+)l'(-) pair look the most convenient way to overcome the background.
Address [Flores-Tlalpa, A.] Univ Nacl Autonoma Mexico, Inst Fis, Apartado Postal 20-364, Mexico City 01000, DF, Mexico, Email: alain@fisica.unam.mx;
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 1029-8479 ISBN Medium
Area Expedition Conference
Notes WOS:000411265800003 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 3501
Permanent link to this record