2008 APS April Meeting and HEDP/HEDLA Meeting
Volume 53, Number 5
Friday–Tuesday, April 11–15, 2008;
St. Louis, Missouri
Session D2: Collider and Heavy Flavor Physics
1:30 PM–3:18 PM,
Saturday, April 12, 2008
Hyatt Regency St. Louis Riverfront (formerly Adam's Mark Hotel),
Room: St. Louis D
Sponsoring
Unit:
DPF
Chair: Robert Cahn, Lawrence Berkeley National Laboratory
Abstract ID: BAPS.2008.APR.D2.1
Abstract: D2.00001 : The Accomplishments of the CESR/CLEO Program*
1:30 PM–2:06 PM
Preview Abstract
Abstract
Author:
Sheldon Stone
(Syracuse University)
The CLEO experiment, that uses the Cornell Electron Storage Ring
(CESR), took data from Nov. 1979 to April 2008. Both the machine
and the detector have gone through several different major phases
caused by implementing new technologies, mostly locally
developed. The improved sensitivities usually resulted in major
discoveries. Many particles were first seen at CLEO and many
important decay modes were first seen, or measured with far more
accuracy than done before. Discoveries include the first
observations of the $\Upsilon(3S)$, $\Upsilon(4S)$, $B^0$, $B^-$
$D_S$,
$\Upsilon(1D)$ and $D_{SJ}(2460)$ mesons, and the $\Sigma_c^+$,
$\Sigma_c^{*+}$, $\Sigma_c^{*++}$, $\Sigma_c^{*0}$, $\Xi_c^{0}$,
$\Xi_c^{*0}$, and $\Xi_c^{*+}$ baryons. First observations of
new processes include $b$-quark semileptonic decays, including
the rare semileptonic decay $b\rightarrow u\ell\nu$, the
``Penguin" process $b\rightarrow s\gamma$, and the important
exclusive decays $B\rightarrow J/\psi K_S$ , and
$D^+\rightarrow\mu^+\nu$. Recently, the decay rates for
$D_S^+\rightarrow\mu^+\nu$ and $D_S^+\rightarrow\tau^+\nu$ have
been measured with unprecedented accuracy, posing a challenge to
Lattice QCD calculations. New accelerator and detector
technologies have also had an impact on ensuing particle physics
experiments and detectors in other fields. Decreasing the size of
the CESR beams in the interaction region (so called micro-beta
sizes) led to a large increases in instantaneous luminosity.
Multi-bunch schemes, where many particle bunches and bunch trains
are are brought into collision also increased the luminosity. In
a parallel effort, CESR has maintained a cutting edge synchrotron
radiation facility that has produced many interesting results.
Pioneering detector technologies were implemented in the areas of
electromagnetic calorimetry, tracking, vertexing and particle
identification. For example, in calorimetry, CLEO developed a
system using CsI crystals with photodiode read-out inside a 1.5 T
magnetic field, that provides excellent energy resolution as well
as accurate measurements of photon positions and angles. Particle
identification has a long history of developments starting with a
separate stand-alone dE/dx system that was replaced with a 51
layer drift chamber having dE/dx measurement in each layer, and
finally adding a Ring Imaging Cherenkov detector using LiF
radiators and Triethylamine based wire-chamber photon-detectors.
I will review these achievements and some of their impacts.
*Supported by the National Science Foundation and Dept. of Energy
To cite this abstract, use the following reference: http://meetings.aps.org/link/BAPS.2008.APR.D2.1