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The cross section per nucleon is evaluated with assumption of the linear atomic number dependence. SIG(C=NEUTRINO) and SIG(C=ANTINEUTRINO) are corresponded to the NUMU and NUMUBAR data, respectevly. CLOOP-OVER.
The dijet angular distribution is measured in the Collider Detector at Fermilab. This measurement covers higher mass ranges and larger scattering angles than previously possible. Good agreement is observed between the data and both leading-order [O(αs2)] and next-to-leading order [O(αs3)] QCD calculations. A limit on quark compositeness of Λc>1.0 TeV is obtained.
No description provided.
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We have performed a search for the 1P1 state of charmonium resonantly formed in p¯p annihilations, close to the center of gravity of the 3PJ states. We report results from the study of the J/ψ+π0 and J/ψ+2π final states. We have observed a statistically significant enhancement in the p¯+p→J/ψ+π0 cross section at √s ≃3526.2 MeV. This enhancement has the characteristics of a narrow resonance of mass, total width, and production cross section consistent with what is expected for the 1P1 state. In our search we have found no candidates for the reactions p¯+p→J/ψ+π0+π0 and p¯+p→J/ψ+π++π−.
No description provided.
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A measurement of the cross-sections for single and double prompt photon production in p p interactions at s = 630 GeV is presented. The data sample corresponds to an integrated luminosity of 13.2 pb −1 . The results are in good agreement with the predictions of perturbative QCD. The signal from double prompt photon production has a statistical significance of 4.3 standard deviations.
There is an overall systematic error of 9 pct not included in the table.
Errors quoted include statistical and all PT dependent systematic uncertainties. There is in addition a 6.8 pct overall normalization uncertainty.
Total interaction cross sections have been measured for 8 Li on C and Pb targets, for 9 Li on C, Al, Cu, Sn and Pb targets, as well as for 11 Li on C, Sn and Pb targets at about 80 MeV/nucleon. In addition, 2n-removal cross sections for 11 Li have been extracted. These measurements are used to determine the nuclear and the electromagnetic part of the cross sections for the different projectile-target combinations. The experimental results are compared to different model calculations. These comparisons allow one to draw conclusions on the matter density distribution of the neutron-rich lithium isotope 11 Li. By comparing our data on the electromagnetic dissociation of 11 Li with all the other data available in the literature, we are able to put constraints on the dipole-strength distribution in 11 Li.
Axis error includes +- 0.0/0.0 contribution (?////).
The 2m hydrogen bubble chamber was exposed to a separated beam of α-particles from the ITEP synchrotron. The momentum of the 4 He-nuclei beam averaged over the bubble-chamber fiducial volume was equal to 2.7 GeV/ c (the kinetic energy of the initial protons in the nuclear rest frame was T p = 220 MeV). The total and topological cross sections were measured as well as the cross section of separate 4 He-p interaction channels and the differential cross sections d σ d t of the elastic 4 He-p scattering. The experimental results have been compared with the data of the previous experiments and with the theoretical predictions based on the Glauber-Sitenko multiple-scattering theory.
No description provided.
The CCFR Collaboration presents a measurement of scaling violations of the nonsinglet structure function and a comparison to the predictions of perturbative QCD. The value of ΛQCD, from the nonsinglet evolution with Q2>15 GeV2 and in the modified minimal-subtraction renormalization scheme, is found to be 210±28(stat)±41(syst) MeV.
The CONST(N=LAMBDA-QCD) is extracted from the measurement of scaling violations of the nonsinglet structure function.
We present a measurement of jet shapes in p¯p collisions at √s =1.8 TeV at the Fermilab Tevatron using the Collider Detector at Fermilab (CDF). Qualitative agreement is seen with the predictions of recent next-to-leading [O(αs3)] calculations and with leading logarithm QCD based Monte Carlo simulations. The dependence of the jet shape on transverse energy is studied.
No description provided.
We report the results on the electromagnetic dissociation of 14.5A GeV28Si and 200A GeV16O projectiles in nuclear emulsion. The overall charge changing production cross sections are determined experimentally and are found to agree reasonably well with those computed theoretically. The relative rate as a function of decay energy for various reaction channels are parameterized in terms of an exponential function. Majority of the events in the most prominent decay modes can be attributed to the excitation of giant dipole resonances. Multiplicity distributions of α particles emerged from nuclear as well as electromagnetic interactions are also investigated.
Electromagnetic dissociation.
Electromagnetic dissociation.
The cross section is calculated from the relation sigma=f/ro*lambda, were ro=7.898*10**22 atoms per cm**3 and f is a weight factor which is unity for nuclear interactions produced by all the emulsion targets, for AG f=0.62.
Results are presented for the spin-spin correlation parameters CSS and CLS for free np elastic scattering at neutron beam kinetic energies of 484, 634, 720, and 788 MeV and c.m. angles between 25° and 80°. The measurements were performed with a polarized neutron beam and a polarized proton target. These are the first measurements of this type to be reported in the forward angular region with a free polarized neutron beam. The observables CSS and CLS are both small at all energies, except for CLS at 788 MeV, which is larger than phase-shift analysis predictions by more than one standard deviation for most of the measured points.
No description provided.
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