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Title: Radiative Bottomonium Spectroscopy at the Y(2, 3S) Resonances at BaBar

The compact bound state consisting of a bottom and anti-bottom quark pair interacting via the strong nuclear force is called “bottomonium.” A wealth of long-lived bottomonium states can be both experimentally produced and theoretically described, providing a unique tool to probe calculation techniques with experiment. Bottomonia with total angular momentum J = 1 and orbital angular momentum L = 0 at a variety of radial excitations n – called Υ(nS) – can be produced at electron-positron colliders. The BABAR experiment, located at the interaction point of such a collider (the PEP-II storage ring), has observed 122 million Υ(3S) and 100 million Υ(2S) decays. Some of these involve a transition to the bottomonium state χbJ (nP) (L = 1 and J = (0, 1, 2)), emitting a photon, with subsequent transition to a lower Υ(nS), also emitting a photon. The final Υ(nS) can be identified through a decay to two muons. The dependence of the branching fractions and photon energies in this process on the spin state of the intermediate χbJ (nP) is a key test of phenomenological models. To this end, this dissertation contains a nearly comprehensive study of these transitions with an emphasis on experimentally optimal discrimination between variousmore » models. This focus spurs innovative techniques that complement a large array of physics results, both presented in detail herein.« less
Authors:
 [1]
  1. Stanford Univ., CA (United States)
Publication Date:
OSTI Identifier:
1091526
Report Number(s):
SLAC-R--1035
DOE Contract Number:
AC02-76SF00515
Resource Type:
Thesis/Dissertation
Research Org:
SLAC National Accelerator Lab., Menlo Park, CA (United States)
Sponsoring Org:
USDOE Office of Science (SC)
Country of Publication:
United States
Language:
English
Subject:
38 RADIATION CHEMISTRY, RADIOCHEMISTRY, AND NUCLEAR CHEMISTRY HEPEX