Published December 1, 2008 | Version v1
Journal article Metadata-only

Study of hadronic transitions between Υ states and observation of Υ(4S)→ηΥ(1S) decay

Creators

  • 1. Laboratoire de Physique des Particules, IN2P3-CNRS et Universite de Savoie, F-74941 Annecy-Le-Vieux (France)
  • 2. Universitat de Barcelona, Facultat de Fisica, Departament ECM, E-08028 Barcelona (Spain)
  • 3. Dipartmento di Fisica, Universita di Bari, I-70126 Bari (Italy)
  • 4. INFN Sezione di Bari, I-70126 Bari (Italy)
  • 5. University of Bergen, Institute of Physics, N-5007 Bergen (Norway)
  • 6. Lawrence Berkeley National Laboratory and University of California, Berkeley, California 94720 (United States)

Description

We present a study of hadronic transitions between Υ(mS) (m=4, 3, 2) and Υ(nS) (n=2, 1) resonances based on 347.5 fb-1 of data taken with the BABAR detector at the PEP-II storage rings. We report the first observation of Υ(4S)→ηΥ(1S) decay with a branching fraction B(Υ(4S)→ηΥ(1S))=(1.96±0.06stat±0.09syst)x10-4 and measure the ratio of partial widths Γ(Υ(4S)→ηΥ(1S))/Γ(Υ(4S)→π+π-Υ(1S))=2.41±0.40stat±0.12syst. We set 90% CL upper limits on the ratios Γ(Υ(2S)→ηΥ(1S))/Γ(Υ(2S)→π+π-Υ(1S))<5.2x10-3 and Γ(Υ(3S)→ηΥ(1S))/Γ(Υ(3S)→π+π-Υ(1S))<1.9x10-2. We also present new measurements of the ratios Γ(Υ(4S)→π+π-Υ(2S))/Γ(Υ(4S)→π+π-Υ(1S))=1.16±0.16stat±0.14syst and Γ(Υ(3S)→π+π-Υ(2S))/Γ(Υ(3S)→π+π-Υ(1S))=0.577±0.026stat±0.060syst.

Additional details

Identifiers

DOI
10.1103/PhysRevD.78.112002;
arXiv
arXiv:0807.2014v2;

Publishing Information

Journal Title
Physical Review. D, Particles Fields
Journal Volume
78
Journal Issue
11
Journal Page Range
p. 112002-112002.11
ISSN
0556-2821
CODEN
PRVDAQ

INIS

Country of Publication
United States
Country of Input or Organization
International Atomic Energy Agency (IAEA)
INIS RN
41002307
Subject category
S72: PHYSICS OF ELEMENTARY PARTICLES AND FIELDS;
Descriptors DEI
BRANCHING RATIO; ETA MESONS; GAMMA RADIATION; MESONS; PARTICLE DECAY; PHOTONS; PIONS MINUS; PIONS PLUS; RESONANCE; STORAGE RINGS
Descriptors DEC
BOSONS; DECAY; DIMENSIONLESS NUMBERS; ELECTROMAGNETIC RADIATION; ELEMENTARY PARTICLES; HADRONS; IONIZING RADIATIONS; MASSLESS PARTICLES; MESONS; PIONS; PSEUDOSCALAR MESONS; RADIATIONS

Optional Information

Notes
(c) 2008 The American Physical Society