We describe a novel approach to particle-detector cooling in which a modular farm of active coolant-control platforms provides independent and regulated heat removal from four recently upgraded ...subsystems of the CLEO detector: the ring-imaging Cherenkov detector, the drift chamber, the silicon vertex detector, and the beryllium beam pipe. We report on several aspects of the system: the suitability of using the aliphatic-hydrocarbon solvent PF
TM-200IG as a heat-transfer fluid, the sensor elements and the mechanical design of the farm platforms, a control system that is founded upon a commercial programmable logic controller employed in industrial process-control applications, and a diagnostic system based on virtual instrumentation. We summarize the system's performance and point out the potential application of the design to future high-energy physics apparatus.
Using 13.7 fb(-1) of data recorded by the CLEO detector at the Cornell Electron Storage Ring, we investigate the spectrum of charmed baryons which decay into Lambda+(c)pi(-)pi(+) and are more massive ...than the Lambda+(c)(2625) baryon. We find evidence for two new states: one is broad and has an invariant mass roughly 480 MeV above that of the Lambda+(c) baryon; the other is narrow with an invariant mass of 596+/-1+/-2 MeV above the Lambda+(c) mass.
We observe signals for the decays {psi}(3770){yields}XJ/{psi} from data acquired with the CLEO detector operating at the CESR e{sup +}e{sup -} collider with {radical}(s)=3773 MeV. We measure the ...following branching fractions B({psi}(3770){yields}XJ/{psi}) and significances: (189{+-}20{+-}20)x10{sup -5} (11.6{sigma}) for X={pi}{sup +}{pi}{sup -} (80{+-}25{+-}16)x10{sup -5} (3.4{sigma}) for X={pi}{sup 0}{pi}{sup 0}, and (87{+-}33{+-}22)x10{sup -5} (3.5{sigma}) for X={eta}, where the errors are statistical and systematic, respectively. The radiative return process e{sup +}e{sup -}{yields}{gamma}{psi}(2S) populates the same event sample and is used to measure {gamma}{sub ee}{psi}(2S)=(2.54{+-}0.03{+-}0.11) keV.
The h{sub c}({sup 1}P{sub 1}) state of charmonium has been observed in the reaction {psi}(2S){yields}{pi}{sup 0}h{sub c}{yields}({gamma}{gamma})({gamma}{eta}{sub c}) using 3.08x10{sup 6} {psi}(2S) ...decays recorded in the CLEO detector. Data have been analyzed both for the inclusive reaction, where the decay products of the {eta}{sub c} are not identified, and for exclusive reactions, in which {eta}{sub c} decays are reconstructed in seven hadronic decay channels. We find M(h{sub c})=3524.4{+-}0.6{+-}0.4 MeV which corresponds to a hyperfine splitting {delta}M{sub hf}(1P){identical_to}<M({sup 3}P{sub J})>-M({sup 1}P{sub 1})=+1.0{+-}0.6{+-}0.4 MeV, and B({psi}(2S){yields}{pi}{sup 0}h{sub c})xB(h{sub c}{yields}{gamma}{eta}{sub c})=(4.0{+-}0.8{+-}0.7)x10{sup -4}.
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