[tau] dipole moments via radiative leptonic [tau] decays

• Published in: The journal of high energy physics Vol. 2016; no. 3; p. 1
• Main Authors: Eidelman, S, Epifanov, D, Fael, M, Mercolli, L, Passera, M
• Format: Journal Article
• Language: English
• Published: Heidelberg Springer Nature B.V 01.03.2016
• Subjects: High energy physics
• ISSN: 1029-8479
• DOI: 10.1007/JHEP03(2016)140

Abstract We propose a new method to probe the magnetic and electric dipole moments of the [tau] lepton using precise measurements of the differential rates of radiative leptonic [tau] decays at high-luminosity B factories. Possible deviations of these moments from the Standard Model values are analyzed in an effective Lagrangian approach, thus providing model-independent results. Analytic expressions for the relevant non-standard contributions to the differential decay rates are presented. Earlier proposals to probe the [tau] dipole moments are examined. A detailed feasibility study of our method is performed in the conditions of the Belle and Belle II experiments at the KEKB and Super-KEKB colliders, respectively. This study shows that our approach, applied to the planned full set of Belle II data for radiative leptonic [tau] decays, has the potential to improve the present experimental bound on the [tau] anomalous magnetic moment. On the contrary, its foreseen sensitivity is not expected to lower the current experimental limit on the [tau] electric dipole moment.