Measurements of K − p elastic scattering have been carried out at 14 momenta between 610 MeV/ c and 943 MeV/ c over the angular range −0.9 < cos θ < 0.9. The results agree well with the best existing data and have significantly smaller errors.
No description provided.
DIFFERENTIAL CROSS SECTION AT 0 DEG CALCULATED FROM DISPERSION RELATIONS AND AT 180 DEG INTERPOLATED FROM BUBBLE CHAMBER MEASUREMENTS.
LEGENDRE POLYNOMIAL FIT, INCLUDING FORWARD AND BACKWARD POINTS.
Elastic and charge-exchange K + n differential cross sections have been measured from K + d interactions from 430 to 940 MeV/ c using spark chambers and scintillation counters. The data have been compared with existing results and in an accompanying paper have been included with other measurements in a phase-shift analysis.
DEUTERIUM TARGET.
NOTE COHERENT ELASTIC SCATTERING ON DEUTERIUM AT FORWARD ANGLES (-T < 0.13 GEV**2) REDUCES THE CROSS SECTION COMPARED WITH FREE NUCLEON ELASTIC SCATTERING.
NOTE COHERENT ELASTIC SCATTERING ON DEUTERIUM AT FORWARD ANGLES (-T < 0.13 GEV**2) REDUCES THE CROSS SECTION COMPARED WITH FREE NUCLEON ELASTIC SCATTERING.
By means of an isospin analysis of the reaction π ± p→ π (N π ) at 16 GeV/ c we have determined the decay angular distributions of the N π system with I= 1 2 produced by isospin zero exchange. Helicity conservation is not observed in the t -channel for the N π mass region below 1.6 GeV, where diffraction dissociation of the proton is supposed to dominate. There are indications for approximate t -channel helicity conservation for N ∗ (1690) production. In the helicity frame, the experimental data are not in agreement with s -channel helicity conservation over the whole N π mass range investigated. Thus the diffractive process N→N π differs both from the process N→N ππ (or π → πππ and K→K ππ ) which approximately conserves t -channel helicity and from the elastic scattering N→N which conserves helicity in the s -channel.
No description provided.
FIT TO ISOSPIN HALF NUCLEON RESONANCE PRODUCTION WITH ISOSPIN ZERO EXCHANGE.
Results are presented for the quasi two-body hypercharge exchange reactions of the type using data from a high statistics bubble chamber experiment. Total and differential cross sections and the momentum transfer dependence of the meson and hyperon resonance single density matrix elements are discussed. Amplitude analyses are performed for the first two reactions. The results are compared with quark model and duality predictions and with those from other related reactions.
No description provided.
No description provided.
No description provided.
The reaction π + n → ω 0 p has been studied at 4 GeV/ c giving a total cross section of 313 ± 26 μ b. The sample of about 3500 ω 0 events produced in the forward direction has been used to determine the differential cross section and the spin density matrix elements. The effective trajectory for unnatural parity exchange has been determined by a comparison of ϱ 00 d σ /d t at different energies. A comparison of ϱ 00 d σ /d t has been made with the similar data for ϱ 0 production in this experiment allowing π-B exchange degeneracy and ϱ-ω interference to be investigated. These methods result in an unnatural trajectory consistent with that expected for the B-meson. A further study of ϱ-ω interference has been made by comparing the reactions π + n → ω 0 p and π − p → ω 0 n at similar energies. Our results on ω and ϱ production are combined with data on K ∗0 and K ∗0 production at 4 GeV/ c and an SU(3) sum rule relating the production of these four mesons is shown to be satisfied.
ASSUMING PREDOMINANTLY NUCLEON SPIN FLIP.
No description provided.
No description provided.
A comparison is made of the low-mass three-meson systems (πππ), (Kππ), (π K K ) and ( K K K ) diffractively produced in the reaction meson + proton → three mesons + proton. Several striking similarities and a few important differences are observed: (i) the reactions are consistent with the assumption that the three mesons decay entirely into a 0 − meson and a 0 + , 1 − or 2 + resonance; (ii) the three-meson mass spectra have a peak ≈ 250 MeV above the effective threshold M eff of the dominant decay mode and then fall off approximately as (mass) −3 ;(iii) the average spin 〈 J 〉 = 0.55 + 1.1 Q eff , where Q eff = M - M eff ; (iv) the average orbital angular momentum 〈 l 〉 increases according to 〈 l 〉 = 0.75 Q eff ; (v) the three-meson states are produced dominantly in unnatural spin-parity states and no evidence for their being resonant is found; (vi) the only natural spin-parity states found are the well-established 2 + resonances A 2 and K ∗ (1420); they have similar properties to the non-resonant unnatural parity states except for a dip at t = 0 in the dσ/d t distributions; (vii) both the unnatural and natural spin-parity states are produced mostly by an exchange of natural parity; (viii) there is evidence for two types of production mechanism with different polarization properties, one approximately conserving helicity in the t -channel and the other in the s -channel.
No description provided.
Inclusive ϱ 0 and f(1270) production are analysed in π + p collisions at 8, 16 and 23 GeV/ c . The ϱ 0 cross section increases with energy such that the ϱ 0 /π − ratio remains constant. Emphasis is laid on cross sections as a function of the transverse momentum and of the Feynman x variable. The ϱ 0 's can be attributed to two sources: some ϱ 0 's are centrally produced, but there is a pronounced forward peak. The distribution of leptons coming from ϱ 0 decay is discussed.
No description provided.
No description provided.
No description provided.
The production of ψ(3.1) mesons is reported for the reactions π−+Fe→μ++μ−+anything, at 200 GeV, and p+Fe→μ++μ−+anything, at 240 GeV. For ψ production, distributions in x≡PLPbeam and P⊥ are given. For x>~0.5, the ratio of the ψ production cross sections in iron for pions to that for protons is found to be 7.4±2.0.
No description provided.
No description provided.
CDB=THESE DATA TO BE MULTIPLIED BY FACTOR 10.0.
We present results on the differential cross-sections for the reactions π + p → K + Σ + (1385) and K − p → π − Σ + (1385) at 10 GeV/ c . For the first time, the same equipment has been used in measuring both reactions, in order to obtain good relative normalization. In the region of low t ( t min to −0.3 (GeV/ c ) 2 ) the two differential cross-sections have similar shape, and show a sharp forward dip indicating a dominant helicity flip contribution. However, the magnitudes of the cross-sections are significantly different, indicating substantial exchange degeneracy breaking. We find the ratio of the integrated cross-sections for the reactions K − p → π − Σ + (1385) and π + p → K + Σ + (1385) over the range −0.3 < t ′ < 0.0 (GeV/ c ) 2 to be 2.0 ± 0.2.
TMIN = -0.013 GEV**2.
TMIN = +0.012 GEV**2.
The differential cross section for neutron-deuteron elastic scattering was measured for four-momentum transfers 0.3 < − t < 2.0 (GeV/c) 2 with incident neutron momenta between 6 and 12.5 GeV/c. The measurement was made with spark chambers at the Argonne ZGS. Results are compared with proton-deuteron elastic scattering at comparable energies as a test of isospin invariance in strong interactions and with the predictions of the Glauber multiple scattering theory. Very good agreement is found.
UNPUBLISHED DATA.
No description provided.
UNPUBLISHED DATA.
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