Measurements of the double-differential $\pi^{\pm}$ production cross-section in the range of momentum $0.5 \GeVc \leq p \le 8.0 \GeVc$ and angle $0.025 \rad \leq \theta \le 0.25 \rad$ in interactions of charged pions on beryllium, carbon, aluminium, copper, tin, tantalum and lead are presented. These data represent the first experimental campaign to systematically measure forward pion hadroproduction. The data were taken with the large acceptance HARP detector in the T9 beam line of the CERN PS. Incident particles, impinging on a 5% nuclear interaction length target, were identified by an elaborate system of beam detectors. The tracking and identification of the produced particles was performed using the forward spectrometer of the HARP detector. Results are obtained for the double-differential cross-sections $ {{\mathrm{d}^2 \sigma}}/{{\mathrm{d}p\mathrm{d}\Omega}} $ mainly at four incident pion beam momenta (3 \GeVc, 5 \GeVc, 8 \GeVc and 12 \GeVc). The measurements are compared with the GEANT4 and MARS Monte Carlo simulation
Double differential PI+ and PI- production cross section in the laboratory system for PI- BE interactions at 3, 5, 8 and 12 GeV for the angular range 0.05 to 0.10 radians.
Double differential PI+ and PI- production cross section in the laboratory system for PI- BE interactions at 3, 5, 8 and 12 GeV for the angular range 0.10 to 0.15 radians.
Double differential PI+ and PI- production cross section in the laboratory system for PI- BE interactions at 3, 5, 8 and 12 GeV for the angular range 0.15 to 0.20 radians.
Measurements of double-differential charged pion production cross-sections in interactions of 12 GeV/c protons on O_2 and N_2 thin targets are presented in the kinematic range 0.5 GeV/c < p_{\pi} < 8 GeV/c and 50 mrad < \theta_{\pi} < 250 mrad (in the laboratory frame) and are compared with p--C results. For p--N_2 (p--O_2) interactions the analysis is performed using 38576 (7522) reconstructed secondary pions. The analysis uses the beam instrumentation and the forward spectrometer of the HARP experiment at CERN PS. The measured cross-sections have a direct impact on the precise calculation of atmospheric neutrino fluxes and on the improved reliability of extensive air shower simulations by reducing the uncertainties of hadronic interaction models in the low energy range. In particular, the present results allow the common hypothesis that p--C data can be used to predict the p--N_2 and p--O_2 pion production cross-sections to be tested.
Double differential cross section for pion production in P-N2 interactions for the pion scattered polar angle range 50 to 100 mrad.
Double differential cross section for pion production in P-N2 interactions for the pion scattered polar angle range 100 to 150 mrad.
Double differential cross section for pion production in P-N2 interactions for the pion scattered polar angle range 150 to 200 mrad.
Inclusive production in proton–proton collisions has been measured at a beam energy of 2.16 GeV using the COSY-ANKE magnetic spectrometer. The resulting spectrum, as well as those corresponding to and correlated pairs, can all be well described using consistent values of the total cross sections for the , , and reactions. While the resulting values for Λ and production are in good agreement with world data, our value for the total production cross section, at an excess energy of , could only be reconciled with other recently published data if there were a highly unusual near threshold behaviour.
Total cross section for the reaction P P --> K+ N SIGMA+.
Total cross section for the reaction P P --> K+ P LAMBDA.
Total cross section for the reaction P P --> K+ P SIGMA0.
The double-differential production cross-section of positive pions, $d^2\sigma^{\pi^{+}}/dpd\Omega$, measured in the HARP experiment is presented. The incident particles are 8.9 GeV/c protons directed onto a beryllium target with a nominal thickness of 5% of a nuclear interaction length. The measured cross-section has a direct impact on the prediction of neutrino fluxes for the MiniBooNE and SciBooNE experiments at Fermilab. After cuts, 13 million protons on target produced about 96,000 reconstructed secondary tracks which were used in this analysis. Cross-section results are presented in the kinematic range 0.75 GeV/c < $p_{\pi}$ < 6.5 GeV/c and 30 mrad < $\theta_{\pi}$ < 210 mrad in the laboratory frame.
Double differential cross section for PI+ production in the angular range 30 to 60 MRAD. Errors are point-to-point only.
Double differential cross section for PI+ production in the angular range 60 to 90 MRAD. Errors are point-to-point only.
Double differential cross section for PI+ production in the angular range 90 to 120 MRAD. Errors are point-to-point only.
A precision measurement of the double-differential production cross-section, ${{d^2 \sigma^{\pi^+}}}/{{d p d\Omega}}$, for pions of positive charge, performed in the HARP experiment is presented. The incident particles are protons of 12.9 GeV/c momentum impinging on an aluminium target of 5% nuclear interaction length. The measurement of this cross-section has a direct application to the calculation of the neutrino flux of the K2K experiment. After cuts, 210000 secondary tracks reconstructed in the forward spectrometer were used in this analysis. The results are given for secondaries within a momentum range from 0.75 GeV/c to 6.5 GeV/c, and within an angular range from 30 mrad to 210 mrad. The absolute normalization was performed using prescaled beam triggers counting protons on target. The overall scale of the cross-section is known to better than 6%, while the average point-to-point error is 8.2%.
Double differential PI+ production cross section in the angular range 30 to 60 mrad.. Errors shown are point-to-point only.
Double differential PI+ production cross section in the angular range 60 to 90 mrad.. Errors shown are point-to-point only.
Double differential PI+ production cross section in the angular range 90 to 120 mrad.. Errors shown are point-to-point only.
K+ meson production in pA (A = C, Cu, Au) collisions has been studied using the ANKE spectrometer at an internal target position of the COSY-Juelich accelerator. The complete momentum spectrum of kaons emitted at forward angles, theta < 12 degrees, has been measured for a beam energy of T(p)=1.0 GeV, far below the free NN threshold of 1.58 GeV. The spectrum does not follow a thermal distribution at low kaon momenta and the larger momenta reflect a high degree of collectivity in the target nucleus.
Double differential K+ production cross section for forward K+ angles < 12 degs. Statistical errors only.
The invariant cross section for K+ production. Statistical errors only.
Ratio of K+ production cross sections for CU/C and AU/C.
Double differential K+cross sections have been measured in p+C collisions at 1.2, 1.5 and 2.5 GeV beam energy and in p+Pb collisions at 1.2 and 1.5 GeV. The K+ spectrum taken at 2.5 GeV can be reproduced quantitatively by a model calculation which takes into account first chance proton-nucleon collisions and internal momentum with energy distribution of nucleons according to the spectral function. At 1.2 and 1.5 GeV beam energy the K+ data excess significantly the model predictions for first chance collisions. When taking secondary processes into account the results of the calculations are in much better agreement with the data.
No description provided.
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In the very heavy collision system Au197+197Au the K+ production process was studied as a function of impact parameter at 1 GeV/nucleon, a beam energy well below the free N-N threshold. The K+ multiplicity increases more than linearly with the number of participant nucleons and the K+/π+ ratio rises significantly when going from peripheral to central collisions. The measured K+ double differential cross section is enhanced by a factor of 6 compared to microscopic transport calculations if secondary processes (ΔN→KΛN and ΔΔ→KΛN) are ignored.
No description provided.
The total K+ cross section is determined by extrapolating and integrating the double differential cross section d2(sig)/d(p)/d(omega) over momentum and solid angle.
We present data on the inclusive neutron spectra produced in the forward direction by the interactions of 23.85 GeV/ c protons in a copper target. The results are in good agreement with the predictions of the triple-Regge model.
No description provided.
Momentum spectra for forward Σ− and Ξ− production by protons on beryllium are presented. Σ− production data for two primary proton momenta are compared to test scaling of the invariant cross section. In addition, the observed single-particle momentum distributions are compared with single-particle spectra from other inclusive reactions initiated by protons.
No description provided.
No description provided.
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