Baryon resonance production in quasi-two-body reactions has been studied for the channels K + p→K°p π + , K + n π + and K + p π ° at beam momenta of 2.53, 2.76 and 3.20 GeV/ c . The production cross sections, four-momentum transfer distributions and density matrix elements are given for the Δ(1236), N ∗ (1400), N ∗ (1500) and N ∗ (1680) states. The reaction K + p→K° Δ ++ (1236) is compared to the line reversed reaction K − n → K °Δ − and the charge-exchange SU(3) sum rule for pseudo-scalar meson plus Δ(1236) is tested.
No description provided.
No description provided.
No description provided.
The differential cross sections of the elastic p p reaction have been measured at 1.2, 1.4, 1.8 and 2.6 GeV/ c incident p momentum. The measurements have been performed at the CERN PS using a system of multiwire proportional chambers. The angular region covers scattering angles from 0 to ∼200 mrad. Interference effects between the Coulomb and the nuclear amplitudes are used to derive the ratio of the real to imaginary part of the forward nuclear amplitude. These ratios are compared with theoretical predictions.
'MS'. 'TBIN'.
'MS'. 'TBIN'.
'MS'. 'TBIN'.
The differential cross sections of the combined elastic and break-up K − d reaction have been measured at 1.21, 1.42 and 2.61 GeV/ c incident K − momentum. The measurements have been performed at the CERN PS using multiwire proportional chambers. The values of the invariant momentum transfer t explored (0.0005<| t |<0.1 GeV 2 ) include the Coulomb-nuclear interference region. The differential cross sections have been analysed in the framework of the Glauber impact-parameter formalism. The observed interference effects have been used to derive the ratio of the real to imaginary part of the forward K − n nuclear amplitude.
SUM OF COHERENT AND BREAK-UP SCATTERING.
SUM OF COHERENT AND BREAK-UP SCATTERING.
SUM OF COHERENT AND BREAK-UP SCATTERING.
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UNPUBLISHED DATA.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UNPUBLISHED DATA.
Results are presented concerning K − d and K − n elastic scattering at an incident momentum of 4.5 GeV/ c . The high-energy Glauber formalism has been used in analyzing the data in which the nucleon scattering amplitudes are parameterized and employing the spherical and quadrupole deuteron form factors. An impulse approximation analysis of the K − n differential scattering cross section fitted to a single exponential of the form d σ /d t ) 0 e Bt , leads to the result (d σ /d t ) 0 = 21.3 + mn ; 5.5 mb/(GeV/ c ) 2 and B = 6.9 + mn ; 0.5 (GeV/ c ) −2 . A global fit has been made to existing K + mn; N two-body scattering data at this energy in order to determine the scattering amplitudes. It was found that the K − n and K − p elastic amplitudes are dominantly imaginary with a relatively small contribution from spin-flip amplitudes. The slopes of the differential elastic cross sections for K − n and K − p are nearly equal, as are those for K + n and K + p. However, the value of the slope for K + is smaller than that for K − at this energy.
No description provided.
No description provided.
No description provided.
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No description provided.
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No description provided.
The differential cross section in the very forward direction has been measured for K − and K + scattering (break-up and coherent) on a deuterium target at an incident momentum of 10 GeV/ c . From these measurements and using a model for the scattering and re-scattering effects in deuterium, we have exploited the Coulomb-nuclear interference to deduce the real part of the K ± n scattering amplitude at a momentum transfer t = 0. The measurements are the first ever obtained for the K + n reaction and the first at this energy for the K − n reaction. A comparison has been made between our results and those predicted from dispersion relations. A new dispersion-relation fit including all the existing K ± n values at different energies has been performed.
SUM OF COHERENT AND BREAK-UP SCATTERING ON DEUTERIUM.
FROM FIT TO D(SIG)/DT OVER -T=0.0018 TO 0.074 GEV**2 ALLOWING FOR COULOMB SCATTERING, DOUBLE SCATTERING, INTERFERENCES AND FERMI MOTION. CORRELATION BETWEEN SLOPE AND RE(AMP)/IM(AMP) IS REFLECTED IN THE GIVEN SYSTEMATIC E RRORS.
We have measured π±p and pp elastic differential cross sections in the range |cosθc.m.|<0.35 for incident momenta from 2 to 9.7 GeV/c for π−p and pp and from 2 to 6.3 GeV/c for π+p. We find that the fixed-c.m.-angle πp differential cross sections cannot be described as simple functions of s. The data are compared to the energy and angular dependence predicted by the constituent model of Gunion, Brodsky, and Blankenbecler.
No description provided.
No description provided.
No description provided.
αα elastic scattering was measured at 4.32 GeV/ c and 5.07 GeV/ c incident momenta. The four-momentum transfer range, extending from −0.05 to −0.77 (GeV/ c ) 2 , covers the first and second minimum regions. The results are compared with calculations based on Glauber theory.
ERRORS SHOWN INCLUDE STATISTICAL ERRORS, QUASIELASTIC CONTRIBUTION SUBTRACTION ERROR, AND AN ASSYMETRIC ERROR RESULTING FROM THE UNCERTAINTIES AS TO THE ORIGIN OF THE WIDENING OF THE ELASTIC PEAK.
ERRORS SHOWN INCLUDE STATISTICAL ERRORS, QUASIELASTIC CONTRIBUTION SUBTRACTION ERROR, AND AN ASSYMETRIC ERROR RESULTING FROM THE UNCERTAINTIES AS TO THE ORIGIN OF THE WIDENING OF THE ELASTIC PEAK.
Differential cross sections of proton Compton scattering have been measured at the Bonn 2.5 GeV synchrotron. 78 data points are presented as angular distributions at photon lab energies of 700, 750, 800, 850, 900, and 950MeV. The c.m. scattering angle ranges from 40°–130°, corresponding to a variation of the four momentum transfer squared betweent=−0.10 tot=−0.96 GeV2 at 700 and 950 MeV, respectively. Two additional differential cross sections have been measured at 1000MeV, 35.6° and 47.4°. The angular distributions show forward peaks whose extrapolations to 0° are consistent with calculated forward cross sections taken from literature. The small angle data (|t| ≲0.2 GeV2) together with the calculated cross sections at 0° are also consistent with the assumption of a slope parameterB of 5 GeV−2. For the first time a rerise of the angular distributions towards backward angles has been observed. It becomes less steep with increasing energy. The most interesting feature of the angular distributions is a sharp structure which appears betweent=−0.55 GeV2 at 700MeV andt=−0.72 GeV2 at 950 MeV. Such a rapid varation of the differential cross section witht has never been ovserved in elastic hadron-hadron scattering or photoproduction processes. It indicates the existence of a dynamical mechanism which could be a peculiarity of Compton scattering.
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