A partial wave analysis of the non-diffractively produced ( K ̄ 0 π + π - system has been performed. The system was produced in the reaction K - p→ K ̄ 0 π + π - n at 10 GeV/ c , measured in the CERN Omega spectrometer. Besides the well-known K ∗ (1420) resonance, we find good evidence for the production of Q 2 (1400) and some indication for Q 1 (1290) production in J P =1 + . In addition we clearly observe a bump in the 1800 MeV region, the properties of which are discussed.
BR(<K RHO>/<K* PI>) FOUND TO BE 0.21 +- 0.08 AND 0.9 +- 0.3 FOR K*(1420) AND K*(1780) RESPECTIVELY.
DENSITY MATRIX FOR JP=2+ IN THE REGION 1.3 < M(K PI PI) < 1.55 GEV.
DENSITY MATRIX FOR JP=3- IN THE REGION 1.6 < M(K PI PI) < 1.9 GEV.
The production of the φ and ω mesons has been studied in the reactions p p → φ(ω)π + π − and p p → φ(ω) ϱ 0 at 0.70–0.76 GeV /c . The c.m. angular distribution of the φ meson in the reaction p p → φπ + π − is found to be consistent with isotropy. The corresponding distribution for ω is not. the ratio σ( p p → φπ + π − ) σ( p p → ωπ + π − ) is (10 ± 2.4) · 10 −3 , which leads to a value of (19 ± 5) · 10 −3 when corrected for the phase-space factor. Implications of this result for the OZI rule are discussed.
No description provided.
No description provided.
Cross sections for various channels in 3 prong + V 0 final states of K − n interactions are obtained at 8.25 GeV/ c . An energy dependence study of the quasi two-body reactions Σ − (1385) + vector meson and ΛB − seem to imply the presence of cuts in the Regge exchange formalism, whereas the reaction Δ(1236) K ∗ (890) does not require such cuts. Upper limits of 1 and 2 μb are found for the reactions K − n → Λ A 1 and K − n → Λ A 2 .
CROSS SECTIONS ARE CORRECTED FOR ALL RESONANCE DECAY MODES EXCEPT FOR K*- DEL0 PRODUCTION WHICH IS ONLY CORRECTED FOR UNSEEN AK0 DECAYS. NO EVIDENCE FOR NON-DIFFRACTIVE A1 AND A2 PRODUCTION.
MAXIMUM LIKELIHOOD EXPONENTIAL FITS TO DIFFERENTIAL CROSS SECTIONS.
Measurements of the total cross section have been performed at the ISR with c.m. energies between 23.5 GeV and 62.5 GeV. Two independent experimental methods have been applied, a measurement of total interaction rate and of small angle elastic scattering. Both experiments give consistent results showing that the total cross section increases by (11.8±1.5) % over the ISR energy range. This experiment has also measured the slope of the forward diffraction peak in elastic scattering at small momentum transfer. The elastic cross section shows the same relative rise as the total cross section, and the ratio λ of elastic to total cross section approaches a constant value of λ =0.178±0.003.
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TOTAL CROSS SECTION FROM (INTERACTION RATE)/(LUMINOSITY). SYSTEMATIC ERROR <0.8 PCT.
TOTAL CROSS SECTION FROM APPLYING THE OPTICAL THEOREM TO SMALL ANGLE ELASTIC SCATTERING EXTRAPOLATED TO T=0.
We have investigated the reactions p p π + π − a ̊ and p p a ̊ p p 2π + 2π − at 100 GeV /c . The p p π + π − final state is dominated by diffractive production of a p π + π − ( or p π + π − ) system which shows a strong tendency to form Δ ++ π − ( or Δ ++ π + ) . The process p p a ̊ Δ ++ Δ ++ is also observed in this reaction, indicating an energy dependence of s −1.5±0.1 . The p p 2π + 2π − channel shows less single diffraction, and has a doubly diffractive component consistent with pomeron factorization. Strong Δ ++ ( Δ ++ ) production is agoain seen, but in contrast to the p p π + π − channel we also observe considerable ϱ 0 production.
No description provided.
The reactions p p → K ∗ (890) X , p p →Σ ± (1385) X and p p → S ∗ (993) X at 12 GeV/ c incident momentum have been studied using 19 000 events with a visible V 0 decay in BEBC. Inclusive production cross sections of these resonances as a function of transverse momentum and rapidity are presented. The contribution of annihilation to the production of the K ∗ (890) is investigated from a comparison with the corresponding pp data.
COMBINDED K*+ AND K*- DATA IN THIS TABLE.
COMBINDED K*+ AND K*- DATA IN THIS TABLE.
No description provided.
We have studied the reaction π − p → X − p followed by the decay X − → ωπ − at 11.2 GeV/ c . The partial-wave analysis in the mass range 1.36–2.0 GeV shows a clear structure in the J P = 3 − , m = 0 wave peaking at 1.67 GeV with a width of ∼0.21 GeV. We interpret this result as resulting from the g → ωπ decay. The differential cross section d σ d t is in agreement with the production of the g-meson through one-pion exchange.
FROM BREIT-WIGNER FIT TO <OMEGA PI-> MASS SPECTRUM. CORRECTED FOR OMEGA TAILS AND OTHER DECAY MODES. CROSS SECTION ORIGINALLY GIVEN IN R. GESSAROLI ET AL., NP B126, 382 (1977).
No description provided.
No description provided.
The reaction\(\bar pp \to \bar \Lambda \Lambda \) has been studied in a bubble chamber experiment at eight incident momenta between 1.50 and 2.06 GeV/c. The differential cross-section, the polarization and the spin correlation coefficients have been measured. They have been compared with the prediction of two theoretical models: the K-meson conspiracy and the exchange of the K*K** degenerate trajectory associated with a Regge cut. The latter model gives the best representation of the data.
No description provided.
No description provided.
POLARIZATION AND SPIN CORRELATION COEFFICIENTS. AVERAGED OVER ALL ANGLES. SEE PAPER FOR DEFINITIONS, MORE DETAILS AND POSSIBLE T-DEPENDENCE.
The absolute normalisation of the polarisation in pp elastic scattering at 24 degrees lab has been determined by means of a double-scattering experiment to an accuracy of +or-1.5% at five energies between 200 and 520 MeV.
No description provided.
Results on the protron structure function, F2, are presented for 0.3<q2<80.0 GeV2 and 10<ν<200 GeV. The results support the conclusions of earlier work at 97 and 147 GeV that scaling is violated. A new value for R=σSσT=0.44±0.25 has been obtained using all the Fermilab proton measurements.
No description provided.
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