We have measured the polarization parameter and differential cross sections in K+p elastic scattering from a polarized target from small |t| and small |u| at five momentum points: 1.7, 2.1, 2.4, 2.7, and 3.0 GeV/c. The polarized-proton target was butanol cooled at 0.5° by a He3-He4 refrigerator; a combination of multiwire proportional chambers and scintillation counters detected the scattered particles. The results for small |u| are discussed in the context of pure Regge-pole models with exchange-degenerate Λ trajectories.
No description provided.
In this paper a comparison of the general features of the reactions K ± p→Q ± p (1) at incident momentum 8.25 GeV/ c is presented. The relevant data derive from events yielding four-constraint fits to the reactions K ± p→K ± π + π − p in exposures of the CERN 2m HBC to RF-separated K + and K − beams. The (K ππ ) effective mass distributions, production angular distributions in the Q region (1.2⩽ M (K ππ )⩽1.5 GeV) and corresponding decay angular distributions are exhibited, and background effects due to N ∗ and Δ production are systematically studied. In particular, it is found that the distributions d σ /d t ′ and d σ /d t for reactions (1) are adequately described by exponential functions over the interval 0.05–0.35 GeV 2 , and exhibit a cross-over effect for momentum transfer squared −0.1 GeV 2 . For both reactions a flattening of d σ /d t ′ for t ′ < 0.05 GeV 2 is observed. By studying the Chew-Low plots and the effects of the different cuts it was found that this flattening cannot be attributed to amplitudes with net s -channel helicity flip different from zero, at least at these energies.
ABOUT 7 PCT RELATIVE NORMALIZATION UNCERTAINTY FOR K+ AND K- SAMPLES.
FITS TO D(SIG)/DT AND D(SIG)/DTP FOR Q+ AND Q- PRODUCTION TO DETERMINE CROSS-OVER POSITIONS. DATA HAVE MASS CUTS TO SELECT K*0 AND REMOVE DEL++ AND DEL0. MIN IS THE MINIMUM VALUE OF -T FOR THE RELEVANT (K PI PI) MASS.
The average charged particle multiplicity, 〈 n ch ( M X 2 )〉, in the reaction K + p→K o X ++ is studied as a function of the mass squared, M X 2 , of the recoil system X and also as a function of the K o transverse momentum, p T , at incident momenta of 5.0, 8.2 and 16.0 GeV/ c . The complete data samples yield distributions which are not independent of c.m. energy squared, s , They exhibit a linear dependence on log ( M X 2 X / M o 2 )[ M o 2 =1 GeV 2 ] with a change in slope occurring for M X 2 ≈ s /2, and do not agree with the corresponding distributions of 〈 n ch 〉 as a function of s for K + p inelastic scattering. Sub-samples of the data for which K o production via beam fragmentation, central production and target fragmentation are expected to be the dominant mechanisms show that, within error, the distribution of 〈 n ch ( M X 2 )〉 versus M X 2 is independent of incident momentum for each sub-sample separately. In particular in the beam fragmentation region the 〈 n ch ( M X 2 )〉 versus M X 2 distribution agrees rather well with that of 〈 n ch 〉 versus s for inelastic K + p interactions. The latter result agrees with recent results on the reactions pp → pX and π − p → pX in the NAL energy range. Evidence is presented for the presence of different production mechanisms in these separate regions.
Two parametrizations are used for fitting of the mean multiplicity of the charged particles : MULT = CONST(C=A) + CONST(C=B)*LOG(M(P=4 5)**2/GEV**2) and MULT = CONST(C=ALPHA)**(M(P=4 5)**2/GEV**2)**POWER.
Differential cross sections for the elastic scattering of K + mesons on protons have been measured at 12 lab momenta between 130 and 755 MeV/ c using a hydrogen filled bubble chamber. The results are consistent with a repulsive S-wave nuclear force. A phase-shift analysis yielded the following values of the low-energy parameters: a S 1 2 =(0.309±0.002) fm , r S 1 2 =(0.032±0.02) fm a P 1 2 =(0.021±0.002) fm , a P 3 2 =(0.013±0.001) fm 3
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The differential cross section for K ± p elastic scattering has been measured in the forward meson direction (0.0008 < t < 0.1 GeV 2 ) in an electronics experiment at incident momenta between 0.9 and 2.06 GeV/ c . The high statistics and absolute normalisation of the data allow a good determination of the real part of the forward nuclear scattering amplitude by means of the Coulomb-nuclear interference effect.
No description provided.
A systematic analysis is presented on the reaction K + p → K ∗0 (890) Δ ++ for nine incident momenta between 4.6–16.0 GeV/ c . Cross sections, differential cross sections and vector meson single density matrix elements are given. As a function of energy, little if any change is observed in either the shapes of the differential cross sections or in the values of the density matrix elements. The data are interpreted in terms of current ideas on t -channel exchange mechanisms.
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Results are presented on an analysis of the reaction K + p → K ∗+ (890) p at 16 GeV/ c and compared with data at lower incident momenta and with corresponding results for the reaction K − p → K ∗− (890) p. It is found for both reactions that the energy dependence of the cross section exhibits a simple ( p − n lab behaviour.
BREIT-WIGNER RESONANCE FITS WITH BACKGROUND.
We present results of measurements of K ± p and p p elastic scattering and of the annihilation reactions p p →π + π − and p p → K + K − at an incident laboratory momentum of 5 GeV/ c . Nearly complete angular distributions were obtained. Results are also presented for π -meson proton elastic scattering in the momentum transfer ranges 2 < − t < 8 (GeV/ c ) 2 (for π + ) and 0.16 < − t < 7 (GeV/ c ) 2 (for π − ). All measurements were done in one experimental geometry. The measured differential cross sections range from 10 to 10 −5 mb/(GeV/ c ) 2 .
-U = T + 8.486 GEV**2.
THE DATA FOR -T = 7.31 TO 8.45 GEV**2 WERE NORMALIZED TO OTHER EXPERIMENTS.
-U = T + 8.304 GEV**2.
None
No description provided.
Cross sections are presented for the K + p interacttions with 2, 3, 4 and 5 particles in the final state for incident momenta between 2.1 and 2.7 GeV/c. The results are compared with those from other experiments at nearby momenta.
Axis error includes +- 0.0/0.0 contribution (?////).
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