New data on the observation and study of a narrow resonance decaying intoΣ−(1,385)K+ have been obtained. The mass of the resonance is (1,956−6+8) MeV/c2, and its width is (27±15) MeV/c2. The resonance is produced in the diffraction dissociation of neutrons on quasi-free nucleons of carbon nuclei. The slope parameter of the differential cross section inPT2 is (9.9±3.0) (GeV/c)−2. The cross section times the branching ratio is (0.22±0.04) μb per nucleon. The resonance has one of the natural spinparities: 5/2+, 7/2− and so on.
YN IS IN ARBITRARY UNITS.
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ARBITRARY UNITS FOR YN.
We have observed inclusive production of D0 and D+ mesons, and their charge conjugates, in e+e− annihilation at 29 GeV on the basis of a data sample of 106 pb−1. These signals correspond to R values of R(D0+D―0)=1.8±0.5 and R(D++D−)=1.2±0.4. Taking the D+ and D0 data together, we measure a charge asymmetry of A=−0.08±0.12 for charmed quarks. A comparison of R(D+D―) with R(D*+D―*) obtained via the process D*+→D0π+ gives a DD* ratio of 1.0−0.2+0.3, indicating that direct D* production dominates over direct D production.
No description provided.
EXTRAPOLATED TO ALL Z.
No description provided.
The electroweak production asymmetry and the decay fragmentation function for e + e − → c c have been measured at s = 29 GeV using charged D ∗ production over the full kinematic range. The data were taken at PEP using the High Resolution Spectrometer. The measured asymmetry is −0.12 ± 0.08. The total production cross section in units of the point cross section corrected for initial state radiation is R D ∗ = 2.7 ± 0.9 .
ASSUMES SIG(D*+) = SIG(D*0). (EXPT. MEASURES D*+ PRODUCTION ONLY). R VALUE CORRECTED FOR INITIAL STATE RADIATION.
No description provided.
Total inclusive cross sections for rho0, ω and f (1270) meson production and the corresponding average multiplicities < n(rho0) > = 0.072+-0.019, < n(ω) > = 0.033+-0.022, < n(f) > = 0 01 +-0.010 have been measured in π-C interactions at 5 GeV/c. It is shown that approximately 8 percent of secondary π- mesons are produced from the meson resonance decay. For the reactions with the production of rho0 mesons the dependence of the inclusive differential cross sections on the rapidity and squared transverse momentum is analysed
No description provided.
No description provided.
We present new measurements of parity conservation in the 293-nm transition in atomic Tl81205. Linearly polarized 293-nm photons, polarization ε^, are absorbed by 6P122 atoms in crossed electric and magnetic fields. The transition probability for each Zeeman component contains a term proportional to ε^·B→ε^·E→×B→ arising from interference between the Stark E1 amplitude βE and the parity-nonconserving E1 amplitude Ep. Our result, [ImEpβ]expt=−1.73±0.33 mV/cm, is compared with estimates based on the standard electroweak model.
Spin of the Tl nucleus is 1/2.
The differential cross sections of the reaction p―p→n―n were measured at 390, 490, 590, 690, and 780 MeV/c. The existence of the theoretically predicted forward dip is confirmed. The results are compared with the predictions of various N―N potential models.
NUMERICAL VALUES SUPPLIED BY F. SAI.
NUMERICAL VALUES SUPPLIED BY F. SAI.
NUMERICAL VALUES SUPPLIED BY F. SAI.
The differential cross section for the reaction π + + d → p + p has been measured at pion momenta between 0.48 and 1.16 GeV c with steps of 20 and 40 GeV c for seven CM proton angles between 6° and 61°. At smaller angles, the measured cross sections show a dip at around 0.7 GeV c , while at larger angles the cross sections vary monotonically as a function of incident momentum. The angular distribution shows a considerably rapid variation with increasing momentum. Legendre polynomial fits of the data are presented.
No description provided.
LEGENDRE POLYNOMIAL COEFFICIENTS. NOTE THE FORM OF THE LEGENDRE EXPANSION DIFFERS BY A FACTOR P**-2 FROM THE CONVENTIONAL ONE.
An exposure of BEBC equipped with the hydrogen-filled TST to the v μ wide band beam at the CERN SPS has been used to study v μ interactions on free protons. About neutral induced interactions have been observed inside the hydrogen and separated into charged current, neutral current and neutral hadron interactions using a multivariate discriminant analysis based on the kinematics of the events. The neutral to charged current cross-section ratio has been determined to be R p v = 0.33 ± 0.04 . When combined with the value of R p v previously determined in the same experiment, the result is compatible with the prediction of the standard SU (2) × U (1) model for sin 2 θ W = 0.24 −0.08 +0.06 and ρ = 1.07 −0.08 +0.06 . Fixing the parameter ρ = 1 yields sin 2 θ W = 0.18 ± 0.04.
No description provided.
The depolarization parameter D NN for pp elastic scattering at θ cm = 90 ° has been measured at twelve momenta between 0.9 and 1.5 GeV/ c . The moduli of the three transversity amplitudes T 1 , T 3 , and T 4 have been extracted from these data and from previous measurements of the differential cross section and spin correlation parameter A NN (90 °). Smooth energy dependence is found for all three amplitude moduli.
Axis error includes +- 3/3 contribution (DUE TO UNCERTAINTIES IN THE TARGET ANALYSING POWER).
Measurements are reported of p̄p total cross sections from 388 to 599 MeV/ c in small momentum steps. Statistical errors are typically ±0.4%and the normalisation uncertainty is ±0.7%. There is no evidence for the “S-meson”.
DATA TAKEN WITH 8.33 CM LH2 TARGET.
DATA TAKEN WITH 1.17 CM LH2 TARGET.
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