The reactions K + n → K + π + π − n, K + n → K 0 π + π − p and K + n → K + π − π 0 p have b investigated in a 3.8 event/μb K + d bubble chamber experiment with incident momenta of 2.2, 2.45 and 2.7 GeV/ c . Channel cross sections are given and the general characteristics of the production processes described. The isobar model is used in an attempt to determine the spin-parity structure of the final states.
No description provided.
No description provided.
We present data on the inclusive neutron spectra produced in the forward direction by the interactions of 23.85 GeV/ c protons in a copper target. The results are in good agreement with the predictions of the triple-Regge model.
No description provided.
The modulus and the phase of the K L o −K S o regeneration amplitude on carbon have been measured. In a momentum range of 16–40 GeV/ c the phase is constant within experimental error bars and coincides with the regeneration phase on hydrogen. Both the modulus and the phase of the regeneration amplitude on carbon are in agreement with optical model predictions.
ASSUMING A CONSTANT PHASE INDEPENDENT OF MOMENTUM, THE CARBON REGENERATION AMPLITUDE HAS A PHASE OF -130 +- 17 DEG.
An accurate measurement of d σ d Ω (π − p → η n ) at 1531 MeV total energy (expanded) up to l = 4 Legendre polynomials) requires reconsideration of previous angular distribution fits which were expanded only up to l = 2 and of subsequent partial-wave analysis. An energy-dependent partial-wave analysis has been performed here for p η ∗ up to 450 MeV/ c . In addition to the well-known S 11 (1520 MeV) resonance, either the P 11 (1532 MeV) or the P 13 (1530 MeV) resonance is found to be strongly coupled to the η-n channel. In both cases, the P 11 (1729 MeV) resonance is needed as is the weakly coupled D 13 (1525 MeV) resonance. The decay states in the ηn channelare compared to the SU(3) and SU(6) W predictions.
No description provided.
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The neutron-proton elastic differential cross section has been measured for incident momenta between 10 and 70 GeV/c and for values of the momentum transfer squared between 0.1 and 2.8 (GeV/c) 2 . The forward peak and the break at about ∣ t ∣ = 1 (GeV/ c ) 2 are very similar to corresponding pp data.
No description provided.
No description provided.
The reaction π−p→X−p, X−→ηπ−, η→γγ has been studied in an optical spark-chamber experiment at the Argonne ZGS (Zero Gradient Synchrotron) at a beam momentum of 6.0 GeV/c and with 0.27≤|t|≤0.42 (GeV/c)2. The ηπ mass spectrum contains about 1400 events in the mass range 0.80<M(ηπ)<1.55 GeV/c2, and is dominated by approximately 1000 events of the type A2−→ηπ−. No structure is discernible within the A2 mass spectrum for an experimental resolution of 7.1 MeV/c2 [16.7 MeV/c2 FWHM (full width at half maximum)]. A single D-wave Breit-Wigner distribution fits the data with a high confidence level, yielding for the A2 the parameters M0=1.323±0.003 GeV/c2 and Γ0=0.108±0.009 GeV/c2. The angular distribution of the decay A2−→ηπ− is analyzed and the resultant density matrix elements have the values ρ11=0.45±0.02, ρ1−1=0.45±0.04, and ρ00=0.09±0.04. All other elements are consistent with zero. Finally, the missing-mass spectrum in the region of the A2 is presented. A signal of 230 events above background per 5-MeV/c2 interval is observed at the A2 peak, with a signal to background ratio of greater than 1:1. A single D-wave Breit-Wigner distribution together with a quadratic background fits the data well, with the parameters for the A2 being M0=1.324±0.003 GeV/c2 and Γ0=0.104±0.009 GeV/c2. Both A2 mass spectra are incompatible with the dipole shape.
No description provided.
THIS FIT ASSUMES ALL OTHER DENSITY MATRIX ELEMENTS (RHO(2M) AND RE(RHO(10))) ARE ZERO SINCE THEY ARE QUITE CONSISTENT WITH ZERO IN A FULL FIT. QUOTED ERRORS INCLUDE SYSTEMATIC ERRORS, WHILE STATISTICAL FITTING ERRORS ARE SHOWN SEPARATELY.
We have measured the cross section for the reaction π−p→π0+anything at an incident momentum of 5 GeV/c. The two γ rays from π0 decays were detected using a 150-element lead-glass hodoscope array. A comparison is given of the inclusive π0 spectrum from hydrogen (obtained through a subtraction of CH2 and C target data) with π0 production from C and Cu.
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We report the observation of a spin 4 resonance from the analysis of the reaction π − p→ K + K − n. The mass and width of the h-meson were determined to be 2050 MeV and 225 MeV. The quantum numbers are J P = 4 + , C = +1 and very probably I G = 0 + .
No description provided.
Single and joint decay angular distributions in the reaction p p → Δ ++ Δ ++ at 9.13 GeV/ c are discussed in the framework of single and double statistical tensors. The t dependence of 12 double statistical tensors is presented. Cross sections for p p → p p π + π − and p p → Δ ++ Δ ++ are determined to be 2.60 ± 0.10 and 0.90 ± 0.10 mb respectively. The results obtained are compared with other experiments mainly at 5.7 and 12 GeV/ c .
No description provided.
No description provided.
FROM FITTING DECAY ANGULAR DISTRIBUTIONS OF BOTH ISOBARS ADDED.
Results are presented for the reactions (1) π+n→pπ+π−, (2) π+n→pπ+π−π0, at an incident pion beam momentum of 11.7 GeV/c. Both reactions show considerable resonance production. Reaction (1) is dominated by ρ0 and f0 production and there is evidence for the variation of the ρ00 width with momentum transfer. Decay angular distributions are presented for the dipion system observed in reaction (1). Reaction (2) shows the production of both dipion and tripion resonances and there is evidence for the associated production of\(\mathcal{N}\)-resonances with the dipion resonances.
No description provided.
DN/DT PLOTTED. ALL RESONANCES ARE DEFINED JUST BY MASS CUTS.
RHO0 MASS REGION OF DIPION SYSTEM. NUMERICAL VALUES TAKEN FROM TABLE 6.1 OF THE THESIS BY D. KEMP (DURHAM 1974).