摘要:

Recent results on radiative transitions from the &psgr;(3095), charmed meson decay, and the Cabibbo‐suppressed decay&tgr; ⇒ K* &ngr;&tgr;are reviewed. The results come primarily from the MarkIIexperiment at SPEAR, but preliminary results from the Crystal Ball experiment on &psgr; radiative transitions are also discussed.

ISSN:0094-243X    

DOI:10.1063/1.2947488

出版商:AIP    

年代:1980

数据来源: AIP

摘要:

We discuss the use of the Crystal Ball detector for the study of eplus;e−annihilations near charm threshold: at the &psgr;(3097), &psgr;′(3685), &psgr;″(3770) and in the “continuum”3770 ≤ &sqrt;s ≤ 4500 MeV. This paper will concentrate on the special techniques available to the Crystal Ball which allow measurement of inclusive &ggr;, &pgr;oand &eegr; cross sections. Preliminary results for these processes at particular center of mass energies are presented. An update of the inclusive and exclusive evidence for the &eegr;c(2980), for the sake of completeness, is given in the Appendix.

ISSN:0094-243X    

DOI:10.1063/1.2947489

出版商:AIP    

年代:1980

数据来源: AIP

摘要:

The last measurements with the DASP detector at the DESY storage ring DORIS have yielded improved results of the properties of the T meson. The leptonic widths are found to be&Ggr;ee(T) = 1.35±0.11±0.22 keVand&Ggr;ee(T′) = 0.61±0.11±0.11 keV. The result on the muonic branching ratio B&mgr;&mgr;and the total width &Ggr;totof the T meson isB&mgr;&mgr;(T) = 2.9±1.3±0.5%and&Ggr;tot = 47 ± 1537 keV. Evidence for theT′ ⇒ &pgr;&pgr;Tdecay is seen from the inclusive spectra.

ISSN:0094-243X    

DOI:10.1063/1.2947490

出版商:AIP    

年代:1980

数据来源: AIP

摘要:

Using the LENA detector at the DORIS e+e−storage ring we have measured the hadronic cross section and the &mgr;‐pair branching ratio of the Y (9.46) resonance. We obtain the electronic width&Ggr;ee = (1.23±0.10±0.14) keVand the massM = (9 461.3±0.7±10.0) MeV, the &mgr;‐pair branching ratioB&mgr;&mgr; = (3.5± 1.5±0.4)%and the total width&Ggr;tot = (35−10 −7+25 +9) keV. For the Y′ resonance, the mass is found to be(10014.0±1.0±10.0) MeV, and&Ggr;ee · &Ggr;had/&Ggr;tot = (0.51±0.07±0.06) keV.

ISSN:0094-243X    

DOI:10.1063/1.2947491

出版商:AIP    

年代:1980

数据来源: AIP

摘要:

Using the CUSB layeredNaIdetector at CESR, we have observed three narrow resonances (&ggr, &ggr;′, &ggr;″) in the&sgr;(e+e⇒ hadrons)over the c. of m. energy interval of 9.4 to 10.3 GeV. Their masses areM(&ggr;)= 9.4345±.0004 GeV,M(&ggr;′)=9.993±.0010 GeV, andM(&ggr;″)=10.3232±.0007 GeV(all in CESR energy scale) and their relative leptonic widths are&Ggr;ee(&ggr;′)/&Ggr;ee(&ggr;)=0.39±.06,&Ggr;ee(&ggr;″)/&Ggr;ee(&ggr;)=0.32±.04, where errors are statistical only. We also found a broad resonance whose massM(&ggr;‴) =10.547±.002and leptonic width&Ggr;ee(&ggr;‴)/&Ggr;ee(&ggr;)=0.25±.07. These values allow us to identify these enhancements as the four lowest triplet S levels of the bound (bb) quark‐antiquark system. The broad natural width (&Ggr; ≃ 13MeV) of the 43S1state indicates that it lies above the threshold for BS production.

ISSN:0094-243X    

DOI:10.1063/1.2947492

出版商:AIP    

年代:1980

数据来源: AIP

摘要:

The performance of the Cornell Electron Storage Ring and the solenoidal magnetic detector CLEO are described. Results of the first six months of data taking are presented. Three narrow resonances and a fourth, broader enhancement have been observed in the energy region 9.3 to 10.7 GeV.

ISSN:0094-243X    

DOI:10.1063/1.2947494

出版商:AIP    

年代:1980

数据来源: AIP

ISSN:0094-243X    

DOI:10.1063/1.2947495

出版商:AIP    

年代:1980

数据来源: AIP

摘要:

This paper is devoted to LEP, the CERN project for an e+e−storage ring of about 30 km circumference, covering an energy range from 22 to 130 GeV. The first chapter contains the main considerations upon which the design and the performance estimates are based. The second chapter describes those engineering aspects in which LEP differs most from smaller machines.

ISSN:0094-243X    

DOI:10.1063/1.2947496

出版商:AIP    

年代:1980

数据来源: AIP

摘要:

Progress in charged particle tracking, electromagnetic shower detection and particle identification in current e+e−colliding beam detectors is reviewed.

ISSN:0094-243X    

DOI:10.1063/1.2947497

出版商:AIP    

年代:1980

数据来源: AIP