Achasov MN, Beloborodov KI, Berdyugin AV, Bogdanchikov AG, Bozhenok AV, Bukin AD, Bukin DA, Burdin SV, Dimova TV, Drozdetsky AA, Druzhinin VP, Dubrovin MS, Gaponenko IA, Golubev VB, Ivanchenko VN, Ivanov PM, Korol AA, Koshuba SV, Lysenko AP, Nesterenko IN, Pakhtusova EV, Perevedentsev EA, Salnikov AA, Serednyakov SI, Shary VV, Shatunov YM, Sidorov VA, Silagadze ZK, Skrinsky AN, Usov YV, Vasiljev AV. Direct measurement of the phi(1020) leptonic branching ratio.
Phys Rev Lett 2001;
86:1698-1701. [PMID:
11290227 DOI:
10.1103/physrevlett.86.1698]
[Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/30/2000] [Indexed: 05/23/2023]
Abstract
The process e(+)e(-)-->mu(+)mu(-) has been studied by the SND detector at the VEPP-2M e(+)e(-) collider in the phi(1020)-resonance energy region. The measured effective phi meson leptonic branching ratio B(phi-->l(+)l(-)) identical with square root of B(phi-->e(+)e(-))B(phi-->mu(+)mu(-))] = (2.89 +/- 0.10 +/- 0.06) x 10(-4) agrees well with the Particle Data Group value B(phi-->e(+)e(-)) = (2.91 +/- 0.07) x 10(-4), confirming mu-e universality. Without additional assumption of mu-e universality the branching ratio B(phi-->mu(+)mu(-)) = (2.87 +/- 0.20 +/- 0.14) x 10(-4) was obtained.
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