HEPData Search

Showing 10 of 200 results

$A_y$ in n-d elastic scattering: a test for three-nucleon calculations

Brogli-Gysin, C. ; Campbell, J. ; Haffter, P. ; et al.

Phys.Lett.B 250 (1990) 11-14, 1990.

Inspire Record 1389638 DOI 10.17182/hepdata.29548

We have measured the analyzing power A y in n-d elastic scattering at 67.0 MeV. The experiment was based on the detection of recoil deuterons, allowing for a precise measurement of the backward angular range. The results are in good agreement with recent three-nucleon calculations which are based on the Paris and Bonn NN potentials.

1 data table

Table 1

No description provided.

$\pi^{-} + p$ elastic scattering in the neighbourhood of $N^{*}_1/2$ (2190)

Busza, W. ; Davis, D.G. ; Duff, B.G. ; et al.

Nuovo Cim.A 52 (1967) 331-341, 1967.

Inspire Record 1185326 DOI 10.17182/hepdata.37568

Elastic π−+p differential cross-section data are presented at the incident-pion momenta 1.72, 1.89, 2.07, 2.27 and 2.46 GeV/c. Resonant behaviour in the coefficients of a Legendre polynomial expansion indicates G- or H-wave resonance. Further analysis using an energy-dependent parametrization of G- and H-waves shows the results to be compatible with the 7−/2 assignment for the , but equally acceptable solutions are obtained with the inclusion of an additional 9+/2 resonance contribution.

5 data tables

Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

More…

$\{pi}-p$ interactions at 1.59 GeV/c

Alitti, J. ; Baton, J.P. ; Berthelot, A. ; et al.

Nuovo Cim. 29 (1963) 515, 1963.

Inspire Record 851185 DOI 10.17182/hepdata.980

Report on the investigation of interactions in π−p collisions at a pion momentum of 1.59 GeV/c, by means of the 50 cm Saclay liquid hydrogen bubble chamber, operating in a magnetic field of 17.5 kG. The results obtained concern essentially the elastic scattering and the inelastic scattering accompanied by the production of either a single pion in π−p→ pπ−π0 and nπ−π+ interactions, or by more than one pion in four-prong events. The observed angular distribution for the elastic scattering in the diffraction region, can be approximated by an exponential law. From the extrapolated value, thus obtained for the forward scattering, one gets σel= (9.65±0.30) mb. Effective mass spectra of π−π0 and π−π+ dipions are given in case of one-pion production. Each of them exhibits the corresponding ρ− or ρ0 resonances in the region of ∼ 29μ2 (μ = mass of the charged pion). The ρ peaks are particularly conspicuous for low momentum transfer (Δ2) events. The ρ0 distribution presents a secondary peak at ∼31μ2 due probably to the ω0 → π−π+ process. The branching ratio (ω0→ π+π−)/(ω0→ π+π− 0) is estimated to be ∼ 7%. The results are fairly well interpreted in the frame of the peripheral interaction according to the one-pion exchange (OPE) model, Up to values of Δ2/μ2∼10. In particular, the ratio ρ−/ρ0 is of the order of 0.5, as predicted by this model. Furthermore, the distribution of the Treiman-Yang angle is compatible with an isotropic one inside the ρ. peak. The distribution of$\sigma _{\pi ^ + \pi ^ - } $, as calculated by the use of the Chew-Low formula assumed to be valid in the physical region of Δ2, gives a maximum which is appreciably lower than the value of$12\pi \tilde \lambda ^2 = 120 mb$ expected for a resonant elastic ππ scattering in a J=1 state at the peak of the ρ. However, a correcting factor to the Chew-Low formula, introduced by Selleri, gives a fairly good agreement with the expected value. Another distribution, namely the Δ2 distribution, at least for Δ2 < 10 μ2, agrees quite well with the peripheral character of the interaction involving the ρ resonance. π− angular distributions in the rest frame of the ρ exhibit a different behaviour for the ρ− and for the ρ0. Whereas the first one is symmetrical, as was already reported in a previous paper, the latter shows a clear forward π− asymmetry. The main features of the four-prong results are: 1) the occurrence of the 3/2 3/2 (ρπ+) isobar in π−p → pπ+π−π− events and 2) the possible production of the ω0→ π+π−π0 resonance in π−p→ pπ−π+π−π0 events. No ρ’s were observed in four-prong events.

4 data tables

Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

More…

$pp$ Interactions at 300-GeV/c: Measurement of the Charged Multiplicity, Total and Elastic Cross-Sections

Firestone, A. ; Davidson, V. ; Lam, D. ; et al.

Phys.Rev.D 10 (1974) 2080, 1974.

Inspire Record 1242 DOI 10.17182/hepdata.25012

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 $8.S0 \pm 0.12$.

2 data tables

Table 1

QUOTED ERRORS INCLUDE EFFECTS OF CORRECTIONS.

Table 2

No description provided.

201 GeV/c Proton Proton Elastic Scattering at Large Momentum Transfer

Hartmann, J.L. ; Orear, J. ; Vrieslander, J. ; et al.

Phys.Rev.Lett. 39 (1977) 975, 1977.

Inspire Record 120624 DOI 10.17182/hepdata.20930

Proton-proton elastic scattering has been measured in the region 4.9<|t|<12.1 GeV2 at a beam momentum of 201 GeV/c. If the form exp(At) is fitted to the data, the exponent A gradually changes from 1.5 to 0.9 GeV−2 over our t range. The data are consistent with the form exp(−6.6p⊥). A comparison with intersecting storage ring results shows that in this kinematical region the slopes are about the same, but dσdt at fixed t is still dropping with energy.

2 data tables

Table 1

7904 ELASTIC EVENTS.

Table 2

1030 ELASTIC EVENTS.

400 GeV/c pp Elastic Scattering: Energy and Angle Dependence at High Momentum Transfer

Conetti, S. ; Hojvat, C. ; Ryan, D.G. ; et al.

Phys.Rev.Lett. 41 (1978) 924, 1978.

Inspire Record 131549 DOI 10.17182/hepdata.20819

Proton-proton elastic scattering at 400 GeV/c has been measured in the region 5.4<−t<14.4 GeV2 with no sign of a second dip or "break." If the data are fitted by exp(At), the slope A decreases from 1.5±0.1 to 0.7±0.2 GeV−2 over the range. At fixed t the 400-GeV/c cross sections are about 0.6 times those at 200 GeV/c in this t range. At fixed θc.m.=15°, dσdt∝s−n where n=9.7±0.3.

2 data tables

Table 1

No description provided.

Table 2

No description provided.

A Combined Analysis of the Hadronic and Leptonic Decays of the $\Z^0$

The OPAL collaboration Akrawy, M.Z. ; Alexander, G. ; Allison, J. ; et al.

Phys.Lett.B 240 (1990) 497-512, 1990.

Inspire Record 294808 DOI 10.17182/hepdata.29720

We report on a measurement of the mass of the Z 0 boson, its total width, and its partial decay widths into hadrons and leptons. On the basis of 25 801 hadronic decays and 1999 decays into electrons, muons or taus, selected over eleven energy points between 88.28 GeV and 95.04 GeV, we obtain from a combined fit to hadrons and leptons a mass of M z =91.154±0.021 (exp)±0.030 (LEP) GeV, and a total width of Γ z =2.536±0.045 GeV. The errors on M z have been separated into the experimental error and the uncertainty due to the LEP beam energy. The measured leptonic partial widths are Γ ee =81.2±2.6 MeV, Γ μμ =82.6± 5.8 MeV, and Γ ττ =85.7±7.1 MeV, consistent with lepton universality. From a fit assuming lepton universality we obtain Γ ℓ + ℓ − = 81.9±2.0 MeV. The hadronic partial width is Γ had =1838±46 MeV. From the measured total and partial widths a model independent value for the invisible width is calculated to be Γ inv =453±44 MeV. The errors quoted include both the statistical and the systematic uncertainties.

4 data tables

Table 1

Errors are statistical and point to point systematic luminosity error of 1 pct.

Table 2

Measured values of e+ e- --> e+ e- cross section.

Table 3

Corrected cross section. Corrections are for t-channel effects and loss of acollinear events near the boundary of the acceptance.

More…

A Comparison of the Shapes of pi+ p and p p Diffraction Peaks from 50-GeV/c to 175-GeV/c

The Fermilab Single Arm Spectrometer Group collaboration Ayres, D.S. ; Diebold, Robert E. ; Maclay, G.J. ; et al.

Phys.Rev.Lett. 37 (1976) 548, 1976.

Inspire Record 108238 DOI 10.17182/hepdata.21073

The ratio of π+p to pp elastic scattering is found to be smoothly varying over the range −t=0.03 to 0.4 GeV2. It is well fitted by a single exponential, indicating the forward behavior must be quite similar for the two reactions.

1 data table

Table 1

ACTUALLY THE DATA ARE THE EXPONENTIAL SLOPE OF THE RATIO OF D(SIG)/DT FOR THE TWO REACTIONS.