The Hadronic Transitions From Υ\Upsilon (2s) to Υ\Upsilon (1s)

Collaboration
Dec, 1986
29 pages
Published in:
  • Z.Phys.C 35 (1987) 283
Report number:
  • DESY-86-169
Experiments:

Citations per year

198719962005201420230123456
Abstract: (Springer)
Using the ARGUS detector at DORIS, we have investigated the hadronic transitions of the Υ(2S) to the Υ(1S). The decays to Υ(1S)π+π−, Υ(1S)π0π0 and Υ(1S)η where the Υ(1S) subsequently decays intoe+e− and Υ(1S)η have been investigated. The transition via two charged pions has also been studied inclusively. We obtain branching ratios of the Υ(2S) into Υ(1S)π+π− of (18.1±0.5±1.0)%, into Υ(1S)π0π0 of (9.5±1.9±1.9)% and into Υ(1S)η of less than 0.5% with 90% confidence. From the exclusive events we find the leptonic branching ratios of the Υ(1S) to beBee=(2.42±0.14±0.14)% andBμμ=(2.30±0.25±0.13)%. Kinematical parameters of the two pion transitions have been investigated in detail and found to be consistent with current algebra and colour-field multipole expansion.
  • ELECTRON POSITRON: COLLIDING BEAMS
  • COLLIDING BEAMS: ELECTRON POSITRON
  • ELECTRON POSITRON: ANNIHILATION
  • ANNIHILATION: ELECTRON POSITRON
  • UPSILON(10020): ELECTROPRODUCTION
  • ELECTROPRODUCTION: UPSILON(10020)
  • UPSILON(10020): HADRONIC DECAY
  • HADRONIC DECAY: UPSILON(10020)
  • UPSILON(10020): BRANCHING RATIO
  • UPSILON(9460): LEPTONIC DECAY