摘要:

Recent experiments have removed the long standing ambiguities in the s‐waveI=0&pgr;&pgr; phase shift, &dgr;oo. There is good evidence for a very sharp threshold‐resonance effect near 980 MeV, and for a broad near‐90° effect in the 700 MeV region.

ISSN:0094-243X    

DOI:10.1063/1.2948688

出版商:AIP    

年代:1972

数据来源: AIP

摘要:

The &pgr;&pgr; phase‐shifts have been determined by a Chew‐Low extrapolation in the &pgr;&pgr; mass region from 500 to 1500 MeV using data of a spark chamber experiment on&pgr;−p ⇒ &pgr;−&pgr;+nat 17.2 GeV/c, which yielded 318,000 events. We find anI = 0s‐wave phase shift which increases slowly, passing through 90° near 900 MeV, and then rises very rapidly. The old “up” solution is eliminated on the basis of fits in the mass region from 900–1000 MeV.

ISSN:0094-243X    

DOI:10.1063/1.2948709

出版商:AIP    

年代:1972

数据来源: AIP

摘要:

We present results of an energy‐dependent &pgr;&pgr; phase shift analysis for &pgr;&pgr; energies between 550 and 1150 MeV. The I = 0 s wave is parametrized in term of a2 × 2M‐matrix coupling &pgr;&pgr; and KK channels. A unique solution is obtained for this wave.

ISSN:0094-243X    

DOI:10.1063/1.2948685

出版商:AIP    

年代:1972

数据来源: AIP

摘要:

An apparent contradiction between a unique set of&dgr;o, and the isotropic term of the &pgr;&pgr; angular distribution is discussed.

ISSN:0094-243X    

DOI:10.1063/1.2948708

出版商:AIP    

年代:1972

数据来源: AIP

摘要:

Absorption models are used as guides to the methodology of cross‐section and moment extrapolations to the pion pole for the purposes of obtaining detailed information on &pgr;&pgr; and K&pgr; phase shifts. Model moments for the reaction&pgr;++p⇒&pgr;++&pgr;−+&Dgr;++are presented.

ISSN:0094-243X    

DOI:10.1063/1.2948710

出版商:AIP    

年代:1972

数据来源: AIP

摘要:

Effects in &pgr;&pgr; and K&pgr; systems similar to that recently observed in &pgr;+&pgr;−at 980 MeV are shown to find a natural interpretation in terms of approximately linear propagation of zeros in the meson‐meson scattering amplitude. Linearity of amplitude zeros is supported by experimental evidence in meson‐baryon two‐body processes at low‐energy, some examples of which are discussed.

ISSN:0094-243X    

DOI:10.1063/1.2948711

出版商:AIP    

年代:1972

数据来源: AIP

摘要:

We present new data on the &eegr;′ based on a sample of events obtained from 870,000 pictures of the BNL 31‐inch hydrogen bubble chamber exposed to a 2.2 GeV/c K−beam. We have measured the &eegr;′ mass, width, and branching ratios, and we present strong evidence that the quantum numbers of the &eegr;′ areJPC = 0−+.

ISSN:0094-243X    

DOI:10.1063/1.2948712

出版商:AIP    

年代:1972

数据来源: AIP

摘要:

Evidence is presented for the existence of a new meson in the 955 MeV mass region. The properties of the M(953) are compared with those of the well‐known &eegr;′ (958).

ISSN:0094-243X    

DOI:10.1063/1.2948678

出版商:AIP    

年代:1972

数据来源: AIP

摘要:

In a scintillation counter experiment we have observed two narrow, neutral mesons denoted Mo(940) and 6o(963) in the reaction&pgr;−p ⇒ Monat 2.4 GeV/c. We also have observed the well‐established &eegr;′(958).

ISSN:0094-243X    

DOI:10.1063/1.2948679

出版商:AIP    

年代:1972

数据来源: AIP

摘要:

Supporting evidence for structure near 960 MeV in the reaction&pgr;−p ⇒ n + (missing‐mass)at 2.5 GeV/c is presented.

ISSN:0094-243X    

DOI:10.1063/1.2948680

出版商:AIP    

年代:1972

数据来源: AIP