摘要:

The preliminary results of a spin-parity analysis of the annihilation reactionsp¯p→&pgr;+&pgr;−&pgr;0,K+K−&pgr;0andK±Ks0&pgr;∓are discussed. The availability of different hadronic final states and partial wave mixtures are the peculiar points of the present analysis. The main features of the experimental data selection, the amplitude and the corresponding constraints are discussed. ©1998 American Institute of Physics.

ISSN:0094-243X    

DOI:10.1063/1.55992

出版商:AIP    

年代:1998

数据来源: AIP

摘要:

The reaction&pgr;−p→f1(1285)&pgr;−p→&eegr;&pgr;+&pgr;−&pgr;−pat 18 GeV/c is being studied. Thef1&pgr;−system is expected to be an important decay mode for a hybrid meson and a previous experiment (BNL E818) has shown some evidence for such a state withJPC=1−+.The existence of a high quality sample off1(1285)/&eegr;(1295)&pgr;−events in the&eegr;&pgr;+&pgr;−&pgr;−pfinal state has been established. Twelve thousand events have been selected from the 1994 E852 data run. A partial-wave analysis of this sample is presented. All significant waves are produced via natural parity exchange (i.e.f2(1270)or&rgr;0(770)exchange). The strongest contributions are from the1++,1−+,and2−+waves. Interesting relative phase motion is observed between these waves. ©1998 American Institute of Physics.

ISSN:0094-243X    

DOI:10.1063/1.56033

出版商:AIP    

年代:1998

数据来源: AIP

摘要:

The study of theI=1,0++states with the OBELIX detector in the channelp¯p→K±KS0&pgr;∓at three different target densities is reported. We discuss in particular the initial state dependence ofa0(980)production and the evidence of an extra scalar state with mass1.29±0.01 GeV/c2and width0.080±0.005 GeV/c2.©1998 American Institute of Physics.

ISSN:0094-243X    

DOI:10.1063/1.56025

出版商:AIP    

年代:1998

数据来源: AIP

摘要:

Results are presented from a partial wave analysis of a sample of centrally produced mesons in the reactionpp→pslow(KsKs)pfast,with 800 GeV/c protons incident on a liquid hydrogen target. The meson system is found to be predominantlyS-wave in the mass range betweenKsKsthreshold and 1.58 GeV/c2. Thef0(1500)is clearly observed in this region. Above 1.58 GeV/c2two solutions are possible, one with mainlyS-wave and another with mainlyD-wave. This ambiguity prevents a unique determination of the spin of thefJ(1710)meson. ©1998 American Institute of Physics.

ISSN:0094-243X    

DOI:10.1063/1.55998

出版商:AIP    

年代:1998

数据来源: AIP

摘要:

Analysis of the 1700–1800 MeV/c2mass region of theKSKS-meson system was carried out on 30000 events obtained with the neutral trigger. A resonance state with mass 1775 MeV/c2and width about 12 MeV/c2is clearly observed at selection of the transverse momentumt>0.25(GeV/c)2.Another sample of events with additional&pgr;0shows peak near threshold due toa0(f0)in the sameKSKSsystem in contrast to elastic reaction&pgr;−p→KSKSn.©1998 American Institute of Physics.

ISSN:0094-243X    

DOI:10.1063/1.56034

出版商:AIP    

年代:1998

数据来源: AIP

摘要:

We calculate the strong decays of hybrid mesons to conventional mesons for all the lowest lyingJPChybrids of flavouruu¯,dd¯,ss¯,cc¯andbb¯.A decay operator developed from the heavy quark expansion of quantum chromodynamics is employed. We show that the selection rule that hybrid mesons do not decay to identical S-wave mesons, found in other models, is preserved. We predict decays of charmonium hybrids, discuss decays ofJPC=1−+exotic isovector hybrids of various masses, and interpret the &pgr;(1800) as a hybrid meson. ©1998 American Institute of Physics.

ISSN:0094-243X    

DOI:10.1063/1.55999

出版商:AIP    

年代:1998

数据来源: AIP

ISSN:0094-243X    

DOI:10.1063/1.55950

出版商:AIP    

年代:1998

数据来源: AIP

摘要:

It is demonstrated that hadronic weak decays ofKand charm mesons are intimately related to hadron spectroscopy. Long standing puzzles in hadronic weak decays of charm mesons can be solved by taking account of dynamical contributions of various hadrons including non-qq¯mesons.

ISSN:0094-243X    

DOI:10.1063/1.56036

出版商:AIP    

年代:1998

数据来源: AIP

摘要:

Current fits toe+e−annihilation below 2.0 GeV and to the corresponding channels in &tgr; decay indicate that the data cannot be readily explained in terms of radial and orbitalqq¯excitations. To clarify and quantify this, a new fit is being made subject to strong theoretical constraints, the3P0model being used to give the hadronic decays of theqq¯states. A fit to the &pgr;&pgr; and &pgr;&ohgr; data is presented, which is shown to fail with the 4&pgr; data. Alternative mechanisms are suggested to explain the discrepancy. ©1998 American Institute of Physics.

ISSN:0094-243X    

DOI:10.1063/1.56035

出版商:AIP    

年代:1998

数据来源: AIP

摘要:

The hybrid quarkonium states are studied using the Born-Oppenheimer expansion. The first step in this expansion is the determination of the energy levels of the gluons in the presence of a static quark-antiquark pair as a function of the quark-antiquark separation. The spectrum of such gluonic excitations is determined from first principles using lattice QCD. ©1998 American Institute of Physics.

ISSN:0094-243X    

DOI:10.1063/1.56000

出版商:AIP    

年代:1998

数据来源: AIP