High-Intensity Electron Storage Rings

Abstract

In recent years a new generation of electron-positron colliders that will have 10-100 times the luminosity of today's machines has started construction. In a similar time frame, a new generation of high-brightness synchrotron light sources has become operational. The scientific goals for these "particle factories" and light sources are explained briefly, and the machine parameters required to achieve them are indicated. Both the accelerator physics and technology issues that result from the required parameters are discussed to show the challenges involved in such significant extensions of accelerator performance. Examples taken from representative projects are used to illustrate the types of solutions adopted to meet these challenges. CONTENTS 1 Work supported by US Department of Energy under contract number DE-AC03-76SF00098.

Experimental Study of Three-body Cabibbo-suppressed D0 Decays and Extraction of Cp Violation Parameters

“…An asymmetric collider makes this possible by allowing the B's from the Υ (4S) decay to move in the laboratory reference frame. The two separate energy rings (one each for e − and e + ) also allow high beam currents and high luminosities [15]. While most of the BABAR data are recorded at the peak of the Υ (4S) resonance, about 10% are taken at a center-of-mass energy 40 MeV lower.…”

Measurement of the Inclusive Branching FractionsB(B^- to D⁺ π^- π^-) and B(B^- to D^{*^+} π^- π^-)

“…Figure 1.2 and Table 1.2 show the spectroscopy of D 0 J . The two D 0 J mesons with j = 1 2 states have broad (a few hundred MeV) resonances while the two j = 3 2 states have narrow resonances (20)(21)(22)(23)(24)(25)(26)(27)(28)(29)(30). Further discussion of the S and D wave decays is presented in Chapter 3.…”