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The Threshold Photoproduction of pi0 on Nucleons and on Few Nucleon Systems

Argan, P. ; Audit, G. ; Bloch, A. ; et al.

Phys.Lett.B 206 (1988) 4, 1988.

Inspire Record 251858 DOI 10.17182/hepdata.29971

The absolute value of the π 0 photoproduction cross section on the proton recently measured near threshold enables to reanalyze previous data collected on 2 H, 3 He, and 4 He relatively to the proton. Absolute cross sections are presented for these nuclei in the energy region extending up to 10 MeV above threshold. The threshold s-wave amplitudes for 2 H and 3 He thus obtained are discussed in relation with the neutron threshold amplitude E ( nπ 0 ) 0+ value.

4 data tables

Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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Inclusion of a deuteron triton component in the energy spectra of slow particles in high-energy proton - nucleus interactions

Atageldeva, U.S. ; Dubovichenko, S.B. ; Spitsyna, S.A. ; et al.

Sov.J.Nucl.Phys. 48 (1988) 1038-1042, 1988.

Inspire Record 457322 DOI 10.17182/hepdata.2240

None

3 data tables

Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

Precise Comparison of Anti-proton - Proton and Proton Proton Forward Elastic Scattering at $\sqrt{s}=24$.3-{GeV}

The UA6 collaboration Breedon, R.E. ; Chapin, T.J. ; Cool, R.L. ; et al.

Phys.Lett.B 216 (1989) 459-465, 1989.

Inspire Record 267044 DOI 10.17182/hepdata.29854

We report results from a measurement of antiproton-proton and proton-proton small-angle elastic scattering at √ s = 24.3 GeV in the range 0.001 ⩽ | t | ⩽ 0.06 (GeV/ c ) 2 . The measurement was performed at the CERN p p Collider by using silicon detectors to observe protons recoiling from a hydrogen cluster-jet target intercepting the stored p and p beams. Fits to the measured differential cross sections yield the ratio of the real to the imaginary part of the forward nuclear scattering amplitude ρ and the nuclear slope parameter b for both p p and pp. We find that the difference Δρ = ρ ( p p ) − ρ( pp ) = 0.031 ± 0.010 agrees with conventional fits and disagrees with the “odderon” fit designed to accommodate the recent UA4 measurement of ρ( p p) at 546 GeV.

3 data tables

Table 1

Data requested from authors.

Table 2

No description provided.

Table 3

Nuclear slopes fixed to world average.

Shadowing in deep inelastic muon scattering from nuclear targets

The European Muon collaboration Arneodo, M. ; Arvidson, A. ; Aubert, J.J. ; et al.

Phys.Lett.B 211 (1988) 493-499, 1988.

Inspire Record 262246 DOI 10.17182/hepdata.29908

Results are presented on the ratio of the inelastic muon-nucleus cross section per nucleon for carbon and calcium relative to that for deuterium. The measurements were made in the kinematic range of low x (0.003–0.1) and low Q 2 (0.3–3.2 GeV 2 ) at an incident muon energy of 280 GeV. The calcium to deuterium ratio shows a significant x dependence which is interpreted as a shadowing effect. No strong Q 2 dependence is observed. This suggests that the effect is due at least partially to parton interactions within the nucleus.

4 data tables

Table 1

VALUES OF Q**2 AT EACH POINT ARE:- 0.52,0.60,0.61,0.61,0.63,0.68,0.90.

Table 2

VALUES OF Q**2 AT EACH POINT ARE:- 1.09,1.25,1.54,1.74,1.76,1.68,1.71, 2.29.

Table 3

VALUES OF X AT EACH POINT ARE:- 0.009,0.011,0.010,0.010,0.010,0.011, 0.013,0.015.

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Measurement of the Spin Rotation Parameter, Beta, in the Reaction $\pi^+ p \to K^+ \Sigma^+$ at 1.60-{GeV}/$c$ and 1.88-{GeV}/$c$

Candlin, D.J. ; Lowe, D.C. ; Peach, K.J. ; et al.

Nucl.Phys.B 311 (1989) 613-629, 1989.

Inspire Record 263837 DOI 10.17182/hepdata.33220

Values of the spin-rotation parameter, β, are measured in the reaction π + p → K + Σ + at incident pion momenta of 1.69 and 1.88 GeV/ c .

2 data tables

Table 1

No description provided.

Table 2

No description provided.

Cross-section Measurement of $\pi^- p \to \pi^- \pi^+ n$ Reaction Near Threshold

The OMICRON collaboration Kernel, G. ; Korbar, D. ; Krizan, P. ; et al.

Phys.Lett.B 216 (1989) 244-248, 1989.

Inspire Record 264989 DOI 10.17182/hepdata.29858

Result of cross section measurements for the reaction π − p → π − π + n are presented. They cover a range of incident pion momenta between 295 and 450 MeV/ c . It is the first time that the cross section has been measured so close to threshold. The experiment was performed with Omicron, a large-solid-angle spectrometer, which enables a measurement of the full set of kinematic variables. In the region of overlap there is a good agreement with other experiments. The extracted value for the chiral-symmetry-breaking parameter ξ is seen to be largely extrapolition dependent but the measured value of -0.5±0.8 leaves Weinberg's prediction of ξ =0 the only remaining choice.

1 data table

Table 1

No description provided.

anti-p He-3 REACTION CROSS-SECTION AT 200-MeV/c

Balestra, F. ; Bossolasco, S. ; Bussa, M.P. ; et al.

Phys.Lett.B 215 (1988) 247-250, 1988.

Inspire Record 264048 DOI 10.17182/hepdata.29876

Inelastic p - 3 He events at 192.8 MeV/ c are detected with a self-shunted streamer chamber. The measured reaction cross section is 392±23.8mb. This result is briefly discussed and compared with other reaction cross sections for low-energy p with light nuclei.

2 data tables

Table 1

Charged prong multiplicity distribution in annihilation events.

Table 2

Measured inelastic cross section.

Direct Photon Production in $\bar{p} p$ Collisions at $\sqrt{s}=630$-{GeV}

The UA2 collaboration Ansari, R. ; Bagnaia, P. ; Banner, M. ; et al.

Z.Phys.C 41 (1988) 395, 1988.

Inspire Record 264998 DOI 10.17182/hepdata.15558

A measurement of the direct production of photons with high transverse momentum from$\bar pp$ collisions at$\sqrt s= 630$ GeV is presented. The structure of events containing a high transverse momentum photon is studied. The results support predictions from QCD theory.

5 data tables

Table 1

The last data point is an average over the interval 60-100 GeV in which 5 events are found.

Table 2

No description provided.

Table 3

No description provided.

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Measurement of $d \sigma / d \Omega$ and A(on) in $\bar{p} p$ Elastic Scattering Between 497-{MeV}/$c$ and 1550-{MeV}/$c$

Kunne, R.A. ; Beard, C.I. ; Birsa, R. ; et al.

Nucl.Phys.B 323 (1989) 1-36, 1989.

Inspire Record 267175 DOI 10.17182/hepdata.48676

Measurements have been made of the differential cross section and asymmetry A on for p p elastic scattering at 15 incident momenta between 497 MeV/ c and 1550 MeV/ c . The angular range where both particles have enough energy to traverse target and setup has been covered. The results are compared with predictions of various N N potential models. None of these models fully explains the present results, although the general trend of the data is predicted correctly.

16 data tables

Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.