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Measurement of nuclear transparencies from exclusive rho0 meson production in muon - nucleus scattering at 470-GeV

The E665 collaboration Adams, M.R. ; Aid, S. ; Anthony, P.L. ; et al.

Phys.Rev.Lett. 74 (1995) 1525-1529, 1995.

Inspire Record 379818 DOI 10.17182/hepdata.42484

Nuclear transparencies measured in exclusive incoherent ρ0 meson production from hydrogen, deuterium, carbon, calcium, and lead in muon-nucleus scattering are reported. The data were obtained with the E665 spectrometer using the Fermilab Tevatron muon beam with a mean beam energy of 470 GeV. Increases in the nuclear transparencies are observed as the virtuality of the photon increases, in qualitative agreement with the expectations of color transparency.

1 data table

Table 1

No description provided.

Nuclear dependence of neutral D meson production by 800-GeV/c protons

The E789 collaboration Leitch, M.J. ; Boissevain, J. ; Carey, T.A. ; et al.

Phys.Rev.Lett. 72 (1994) 2542-2545, 1994.

Inspire Record 371874 DOI 10.17182/hepdata.19694

The nuclear dependence for 800 GeV/c proton production of neutron D mesons has been measured near xF=0 in Experiment 789 at Fermilab. D mesons from beryllium and gold targets were detected with a pair spectrometer and a silicon vertex detector via their decay D→Kπ. No nuclear dependence is found, with a measured α=1.02±0.03±0.02. The measured differential cross section, dσ/dxF, for neutral-D-meson production at 〈xF〉=0.031 is 58±3±7 μb/nucleon. The integrated cross section obtained by extrapolation of the measured cross section to all xF is 17.7±0.9±3.4 μb/nucleon and is consistent with previous measurements.

8 data tables

Table 1

Table 2

Table 3

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The Anti-proton - nuclei annihilation cross-section at the momentum range from 0.70-GeV/c to 2.5-GeV/c

Kuzichev, V.F. ; Lepikhin, Yu.B. ; Smirnitsky, V.A. ;

Nucl.Phys.A 576 (1994) 581-602, 1994.

Inspire Record 363976 DOI 10.17182/hepdata.39981

The results of the measurements of antiproton-nuclei annihilation cross-sections at the momentum range from 0.70 to 2.50 GeV/ c are presented. The A -dependence of the cross-sections is described by the formula σ 0 A α . The behavior of the parameters σ 0 and α indicates the possibility of Coulomb influence on the annihilation processes at low momenta. Comparison with the Glauber theory is carried out. The Coulomb corrections to the Glauber formula for the absorption cross-sections of hadrons by nuclei are calculated. The influence of the real part of the nuclear potential is taken into account. Calculations are made in the frame of the high-energy approach. A comparison with data of annihilation cross-sections of antiprotons on nuclei is made.

9 data tables

Table 1

DETECTOR OF ANNIHILATION COLLECTS 75 PCT OF GENERATED PARTICLES. THE PION BACKGROUND IN THE BEAM WAS NOT GREATER THEN 3-4 PCT (FOR 1.76 GEVABOUT 2 PCT).

Table 2

DETECTOR OF ANNIHILATION COLLECTS 75 PCT OF GENERATED PARTICLES. THE PION BACKGROUND IN THE BEAM WAS NOT GREATER THEN 3-4 PCT (FOR 1.76 GEVABOUT 2 PCT).

Table 3

DETECTOR OF ANNIHILATION COLLECTS 75 PCT OF GENERATED PARTICLES. THE PION BACKGROUND IN THE BEAM WAS NOT GREATER THEN 3-4 PCT (FOR 1.76 GEVABOUT 2 PCT).

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Massive hadron pair production by 800-geV/c protons on nuclear targets

White, H.B. ; Turner, Kathleen R. ; Boca, G. ; et al.

Phys.Rev.D 48 (1993) 3996-4006, 1993.

Inspire Record 359158 DOI 10.17182/hepdata.22668

We report data on proton-nucleon collisions obtained on Fermilab experiment E711, in which high transverse momentum hadrons are produced near 90° in the proton-nucleon center of mass forming high mass states, using an 800 GeV/c proton beam on targets of beryllium, aluminum, iron, and tungsten. The data presented cover the mass range from 7 to 15 GeV/c2, the three dihadron charge states ++, +-, and --, and parton-parton scattering angles up to cosθ*=0.50. We present the differential mass dihadron cross section, as well as the angular and charge dependence of the measurement. The cross section as a function of the parton-parton scattering angle for the three charge states is shown to vary linearly with the value of the atomic weight. While the angular distributions are shown to be independent of the target type, a small dependence on the charge state of the distributions is observed. The data are shown to be in good agreement with extrapolations from previous measurements and phenomenological QCD calculations.

4 data tables

Table 1

Atomic weight dependence as function of the parton-parton scattering angle. This angle (theta cm) is defined as the polar angle between the dihadron axis and the beam director in the rest frame of the massive dihadron state. Cross section parameterised as SIG0(MASS**A). Measurements of A are presented here as POWER(N=A,YN=SIG).

Table 2

Table 3

Errors are statistical only.

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Production of chi charmonium via 300-GeV/c pion and proton interactions on a lithium target

The E705 collaboration Antoniazzi, L. ; Arenton, M. ; Cao, Z. ; et al.

Phys.Rev.D 49 (1994) 543-546, 1994.

Inspire Record 354743 DOI 10.17182/hepdata.42541

We present a measurement and comparison of the χc1 and χc2 production cross sections determined from interactions of 300-GeV/c π± and p with a Li target. We find χc1χc2 production ratios of 0.52−0.27+0.57 and 0.08−0.15+0.25 from reactions induced by π± and p, respectively.

3 data tables

Table 1

The cross section per nucleon.

Table 2

The cross section per nucleon. The differential cross section is fitted by the equation : D(SIG)/D(PT**2)= CONST*EXP(SLOPE*PT), D(SIG)/D(XL) = CONST*(1-(XL-CONST(C=X0))**2)**POWER(C=1) , and D(SIG)/D(XL) = CONST*(1-ABS(XL-CONST(C=XC)))**POWER(C=2).

Table 3

The cross section per nucleon. The differential cross section is fitted by the equation : D(SIG)/D(COS(THETA)) = CONST*(1+CONST*COS(THETA)**2), where THETA is the angle between the MU+ and beam momentum in the CHI/C rest frame.

D*+- production in 250-GeV pi+- N interactions

The E769 collaboration Alves, G.A. ; Amato, S. ; Anjos, J.C. ; et al.

Phys.Rev.D 49 (1994) R4317-R4320, 1994.

Inspire Record 354345 DOI 10.17182/hepdata.42544

We report results from Fermilab experiment E769 on the differential cross sections of D*± charm vector mesons with respect to Feynman-x (xF) and transverse momentum (PT), and on the atomic mass dependence of the production. The D* mesons were produced by a 250 GeV π beam on a target of Be, Al, Cu, and W foils. The dσdxF distribution is fit by the form ((1−xF)n) with n=3.5±0.3±0.1, the dσdPT2 distribution by exp(−b×PT2) with b=0.70±0.07±0.04 GeV−2, and the cross section A dependence by Aα with α=1.00±0.07±0.02. These results are compared to the equivalent parameters for the production of pseudoscalar D0 and D± charm mesons.

5 data tables

Table 1

Data are in arbitrary units and are the weighted averages bin-by-bin for the 3 D0 modes KPI, K3PI and KPIPI0.

Table 2

Data are in arbitrary units and are the weighted averages bin-by-bin for the 3 modes KPI, K3PI and KPIPI0.

Table 3

Results of fit to DSIG/DXL distribution of the form (1-XL)**POWER in the XL range 0.1 to 0.6.

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Transverse momentum distributions for meson resonances at central rapidity and P(t) >= 2-GeV/c

The WA77 collaboration Belogianni, A. ; Benayoun, M. ; Beusch, W. ; et al.

Z.Phys.C 59 (1993) 35-46, 1993.

Inspire Record 354486 DOI 10.17182/hepdata.48468

The transverse momentum distributions for\(\rho ^0 (770),f_2 (1270),K*^0 (892),\bar K*^0 (892)\) and ϕ (1020) have been studied in thept region between 2 and 4 GeV/c and central rapidity. The data analysed come from the WA77 experiment at CERN with a 300 GeV/c π− beam incident on a Be target. These distributions are well described by the functionpt−n withn∼8. A sample of simulated events from the Lund Monte Carlo in the same experimental conditions reproduces well the data.

6 data tables

Table 1

No description provided.

Table 2

Acceptance corrected tranverse momentum distribution.

Table 3

Acceptance corrected tranverse momentum distribution.

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Production of direct photons and neutral mesons at large transverse momenta by pi- and p beams at 500-GeV/c

The FERMILAB-E706 collaboration Alverson, G. ; Baker, W.F. ; Ballocchi, G. ; et al.

Phys.Rev.D 48 (1993) 5-28, 1993.

Inspire Record 353153 DOI 10.17182/hepdata.22583

We present results from the initial run of Fermilab experiment E706. The data include incident π− and p beams at 500 GeV/c on Be and Cu targets, and span the kinematic ranges of transverse momentum and rapidity of 3.5≤pT≤10 GeV/c and −0.7≤yc.m.≤0.7, respectively. We have measured cross sections for π0 and direct-photon production, as well as the ηπ0 production ratio. From the data on Be and Cu, we have extracted the nuclear dependence of π0 production, parametrized as Aα. The cross sections are compared with next-to-leading-log QCD predictions for different choices of the QCD momentum scales and several sets of parton distribution functions.

10 data tables

Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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Cross-sections of the interactions of He nuclei with protons

The Dubna-Kosice-Moscow-Strasbourg-Tbilisi-Warsaw collaboration Glagolev, V.V. ; Lebedev, R.M. ; Pestova, G.D. ; et al.

Z.Phys.C 60 (1993) 421-425, 1993.

Inspire Record 364670 DOI 10.17182/hepdata.14316

4He-p collisions at two values of4He momenta 8.6 GeV/c and 13.6 GeV/c as well as the3He-p collisions at 13.5 GeV/c have been studies using the one-meter JINR hydrogen bubble chamber. Total, elastic, topological and reaction cross sections have been measured. The cross sections have been determined on a sample of minimum biased events.

15 data tables

Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.