Direct measurement of the phi(1020) leptonic branching ratio

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(-))...

Ausführliche Beschreibung

Gespeichert in:

Bibliographische Detailangaben
Veröffentlicht in:	Physical review letters 2001-02, Vol.86 (9), p.1698-1701
Hauptverfasser:	Achasov, M N, Beloborodov, K I, Berdyugin, A V, Bogdanchikov, A G, Bozhenok, A V, Bukin, A D, Bukin, D A, Burdin, S V, Dimova, T V, Drozdetsky, A A, Druzhinin, V P, Dubrovin, M S, Gaponenko, I A, Golubev, V B, Ivanchenko, V N, Ivanov, P M, Korol, A A, Koshuba, S V, Lysenko, A P, Nesterenko, I N, Pakhtusova, E V, Perevedentsev, E A, Salnikov, A A, Serednyakov, S I, Shary, V V, Shatunov, Y M, Sidorov, V A, Silagadze, Z K, Skrinsky, A N, Usov, Y V, Vasiljev, A V
Format:	Artikel
Sprache:	eng
Online-Zugang:	Volltext
Tags:	Tag hinzufügen Keine Tags, Fügen Sie den ersten Tag hinzu!

Beschreibung
Zusammenfassung:	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.
ISSN:	0031-9007 1079-7114
DOI:	10.1103/PhysRevLett.86.1698