We have measured, as a function of transverse momentum (p⊥), the invariant cross section Edσd3p for the production of π±, K±, p, p¯, d, and d¯ in proton collisions with a tungsten (W) target at incident proton energies of 200, 300, and 400 GeV. The measurements were made in the region of 90° in the c.m. system of the incident proton and a single nucleon at rest. Measurements were also made with 300-GeV protons incident on Be, Ti, and W targets of equal interaction length. These p-nucleus measurements, which show a strong dependence on atomic number at high p⊥, were used to extract effective proton-nucleon cross sections by extrapolation to atomic number unity. At large values of the scaling variable x⊥=2p⊥s, where s is the square of the c.m. energy, the pion data are found to be well represented by the expression (s)−ne−ax⊥, with n=11.0±0.4 and a=36.0±0.4. x⊥<0.35, where similar measurements have been made at the CERN ISR, our data are in good agreement with the ISR data.
No description provided.
No description provided.
No description provided.
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ONE EVENT SEEN - PROBABLY AN ANTIPROTON.
The polarized target asymmetry for γ + p → π + + n was measured at c.m. angles around 130° for the energy range between 0.3 and 1.0 GeV. A magnetic spectrometer system was used to detect π + mesons from the polarized butanol target. The data show two prominent positive peaks at 0.4 and 0.8 GeV and a deep minimum at 0.6 GeV. These features are well reproduced by the phenomenological analysis made by us.
No description provided.
Targets made of C, Al, Cu, Pb, and U were exposed to π+, π−, and proton beams of 9.92 and 19.85 GeV/c (for p-Pb only) at the Brookhaven AGS. A magnetic spectrometer with spark chambers was used to detect elastically scattered particles in the Coulomb-nuclear interference region (5-35 mrad). Differential cross sections are presented and compared with an optical model, taking full account of multiple scattering in the target.
X ERROR TARG.THICKN. = 0.10 RAD.LENGTH. X ERROR D(THETA) = 0.3000 MRAD.
X ERROR TARG.THICKN. = 0.10 RAD.LENGTH. X ERROR D(THETA) = 0.3000 MRAD.
X ERROR TARG.THICKN. = 0.10 RAD.LENGTH. X ERROR D(THETA) = 0.3000 MRAD.
Total cross sections of π± and K± on protons and deuterons have been measured at 50, 100, 150, and 200 GeV/c. All of the cross sections rise with increasing momentum.
No description provided.
PARTICLE-ANTIPARTICLE CROSS SECTION DIFFERENCES - SOME COMMON ERRORS CANCEL.
Proton and antiproton total cross sections on protons and deuterons have been measured at 50, 100, 150, and 200 GeV/c. The proton cross sections rise with increasing momentum. Antiproton cross sections fall with increasing momentum, but the rate of fall decreases between 50 and 150 GeV/c, and from 150 to 200 GeV/c there is little change in cross section.
No description provided.
ANTIPARTICLE-PARTICLE CROSS SECTION DIFFERENCES.
In a 35 000-picture exposure of the 30-in. hydrogen bubble chamber to a 300-GeV/c proton beam at the Fermi National Accelerator Laboratory, 10054 interactions have been observed. The measured total cross section is $40.68 \pm 0.55$ mb, the elastic cross section is $7.89 \pm 0.52$ mb, and the average charged-particle multiplicity for inelastic events is $8.S0 \pm 0.12$.
QUOTED ERRORS INCLUDE EFFECTS OF CORRECTIONS.
No description provided.
We have observed muons produced directly in Cu and W targets by 300-GeV incident protons. We find a yield of muons which is approximately a constant fraction (0.8·10−4) of the pion yield for both positive and negative charges and for transverse momenta between 1.5 and 5.4 GeV/c.
No description provided.
Relative rates for deep inelastic neutrino and antineutrino scattering without a finalstate muon have been measured. For neutrinos the result is Rν=σ(νμ+nucleon→νμ+hadrons)σ(νμ+nucleon→μ−+hadrons)=0.11±0.05. The corresponding ratio for antineutrinos is Rν¯=0.32±0.09.
No description provided.
In a 48 000-picture exposure of the Fermilab 30-inch hydrogen bubble chamber to a 205 GeV/ c π − beam, we have measured 169 events of the reaction, π − p → π − π + π − p, with a cross section of 635 ± 61 μ b. This reaction proceeds almost entirely via low mass π − → 3 π and p → p ππ dissociation. Factorization is satisfied for p → pππ dissociation in πp and pp interactions.
No description provided.
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