摘要:

This paper describes the results of an experiment studying the reaction &pgr;+p → &Dgr;++&pgr;0&pgr;0using the Argonne National Laboratory 1.5 m streamer chamber combined with a lead glass hodoscope. The results of an energy‐independent amplitude analysis from threshold to 2.3 GeV are presented. In this analysis the f0(1270), the h0(2040), and a JP=2+state at 1.8 GeV with a width of 0.280 GeV are observed. The amplitude ambiguity arising from analyses of &pgr;+&pgr;− → &pgr;+&pgr;−data in the 1.6 GeV region is resolved in favor of the &bgr;‐type solution. An energy‐dependent S‐wave phase shift analysis from 1.0 to 1.5 GeV is presented.

ISSN:0094-243X    

DOI:10.1063/1.34463

出版商:AIP    

年代:1984

数据来源: AIP

摘要:

Results on exclusive photoproduction of various multiparticle states are presented and, where possible, comparisons are made with e+e−annihilation results in the mass range 1 to 2 GeV. The data are suggestive of a new isoscalar vector meson, the &ohgr;′(1670), decaying via &rgr;&pgr;, but fail to confirm the existence of the &fgr;′(1680) expected in KK¯&pgr; and &ohgr;&pgr;+&pgr;−photoproduction. In production of &ohgr;&pgr;0, a &rgr;′(1250) state is not required to fit the data which are explained as due to the B‐meson. Evidence for photoproduction of the H‐meson is also presented.

ISSN:0094-243X    

DOI:10.1063/1.34460

出版商:AIP    

年代:1984

数据来源: AIP

摘要:

4 methods are described for determining the &pgr;0life time directly from the electron production rates from assemblies of gold foils, traversed by high energy protons. A preliminary value of (0.77±0.05) ⋅ 10−16sec has been obtained in a short test run, in good agreement with the previous world average. The final experiment aims at a 1 percent accuracy.

ISSN:0094-243X    

DOI:10.1063/1.34472

出版商:AIP    

年代:1984

数据来源: AIP

摘要:

The BNL/CCNY group1has observed and performed a partial wave analysis on ∼4000 (22 GeV) &pgr;−p → &fgr;&fgr;n events. The OZI suppression has been found to be almost completely broken down. The &fgr;&fgr; spectrum is found to be composed almost entirely of IGJPC=0+2++partially waves which occur in S and D‐waves with spin zero and spin two. Assuming 1) QCD is correct, and 2) the OZI rule is universal for weakly coupled glue in disconnected Zweig diagrams due to the creation or annihilation of new types of quarks; it is concluded that one to three primary glueballs with the above quantum numbers are responsible for the observed data.

ISSN:0094-243X    

DOI:10.1063/1.34478

出版商:AIP    

年代:1984

数据来源: AIP

摘要:

The present experimental status on the KK¯&pgr; final state below 1.6 GeV/c2is reported. In this low mass range the KK¯&pgr; system is dominated by the production of 3 resonances: The D, the E/c and the D′. The possibility of having around the E mass two different states O−+and 1++has been discussed. (AIP)

ISSN:0094-243X    

DOI:10.1063/1.34479

出版商:AIP    

年代:1984

数据来源: AIP

摘要:

the role of pseudoscalar mesons in the development of current understanding of the strong interactions is discussed. In particular the I=0 pseudoscalars, &eegr;,&eegr;′, &eegr;*(1275) and &tgr;(1440) are discussed. A recent successful calculation of the &eegr; and &eegr;′ masses within the bag model is discussed and the interpretation of the &tgr;(1440) is commented upon. (AIP)

ISSN:0094-243X    

DOI:10.1063/1.34455

出版商:AIP    

年代:1984

数据来源: AIP

摘要:

The role of glue in spectroscopy is discussed and some glueball candidates are examined. This new field of interest concerns hybrid states of valence quarks and valence gluons. The comments are presented in the context of the Bag models. (AIP)

ISSN:0094-243X    

DOI:10.1063/1.34456

出版商:AIP    

年代:1984

数据来源: AIP

摘要:

The current status of various glueball properties such as level ordering, masses, production, and decay is reviewed. Glueball candidates &igr;(1440), &thgr;(1670), gT(2160), gT(2320), and 0(2.3‐3.4) are examined. A simple model which incorporates the mixing of the glueball candidate &igr;(1440) with quarkonium states &eegr;(549) and &eegr;′(958), and of the &thgr;(1670) with f(1270) and f′(1515) is presented; neither the &igr;(1440) nor the &thgr;(1670) can be consistently interpreted as a glueball in this framework. A 5×5 model of Palmer and Pinsky which also includes radial excitation of the &eegr; an &eegr;′ yields two solutions for the pseudoscalar system, the preferred one of which has &igr;(1440) being mainly an ss¯ radial excitation, and a second solution in which the &igr;(1440) is mixed strongly with the &eegr;′(960) and is about half bare glueball. The current leading glueball candidates are the &fgr;&fgr; enhancements at 2160 and 2320 MeV.

ISSN:0094-243X    

DOI:10.1063/1.34457

出版商:AIP    

年代:1984

数据来源: AIP

摘要:

We have investigated the Coulomb dissociation of charged pions and kaons on heavy nuclei. New values for the electromagnetic transition rates &Ggr;(&rgr;± → &pgr;±&ggr;) and &Ggr;(K*± → K±&ggr;) have been extracted from the data using the Primakoff formalism. The first measurements for &Ggr;(A2+ → &pgr;+&ggr;), &Ggr;(K**+(1430) → K+&ggr;), &Ggr;(B+(1235) → &pgr;+&ggr;), and &Ggr;(A1+ → &pgr;+&ggr;) will also be presented.

ISSN:0094-243X    

DOI:10.1063/1.34458

出版商:AIP    

年代:1984

数据来源: AIP

摘要:

The SLAC Hybrid Facility Photon Collaboration has undertaken a study of vector mesons produced in 19 GeV &ggr;‐proton collisions. A major goal of this research is to search for radial excitations of &rgr;, &ohgr;, and &Jgr; mesons. This report presents evidence for a radial excitation of the &rgr;(770) produced diffractively in the reaction &ggr;p−≳p&rgr;′ and decaying via &rgr;′−≳&pgr;+&pgr;−.

ISSN:0094-243X    

DOI:10.1063/1.34459

出版商:AIP    

年代:1984

数据来源: AIP