HEPData Search

Results are presented of an investigation of the polarization of recoil protons appearing in elastic 1r+ -p scattering through an angle of 140 ± 8° in the c.m.s. at an energy of 307 ± 5 Mev. A polarization value P 1 = -0.19 ± 0.17 has been deriver from the data on the magnitude of the left-right asymmetry in elastic scattering of recoil protons on photographic emulsion nuclei. Phase shifts satisfying the indicated polarization value and consistent with the differential cross section for elastic scattering of 71"+ -mesons by protons are given by Eq. (1). Problems connected with the use of various phase shift sets for analysis of the experimental data are discussed.

1 data table

Table 1

No description provided.

Multiple Meson Production in Proton-Proton Collisions at 2.85 Bev

Hart, E.L. ; Louttit, R.I. ; Luers, D. ; et al.

Phys.Rev. 126 (1962) 747-756, 1962.

Inspire Record 47769 DOI 10.17182/hepdata.26782

Measurements have been made on 753 four-prong events obtained by exposing the Brookhaven National Laboratory 20-in. liquid hydrogen bubble chamber to 2.85-Bev protons. The partial cross sections observed for multiple meson production reactions are: pp+−(p+p→p+p+π++π−), 2.67±0.13; pn++−, 1.15±0.09; pp+−0, 0.74±0.07; d++−, 0.06±0.02; four or more meson production, 0.04±0.02, all in mb. Production of two mesons appears to occur mainly in peripheral collisions with relatively little momentum transfer. In cases of three-meson production, however, the protons are typically deflected at large angles and are more strongly degraded in energy. The 32, 32 pion-nucleon resonance dominates the interaction; there is some indication that one or both of the T=12, pion-nucleon resonances also play a part. The recently discovered resonance in a T=0, three-pion state appears to be present in the pp+−0 reaction. Results are compared with the predictions of the isobaric nucleon model of Sternheimer and Lindenbaum, and with the statistical model of Cerulus and Hagedorn. The cross section for the reaction π0+p→π++π−+p is derived using an expression from the one-pion exchange model of Drell.

1 data table

Table 1

No description provided.

Proton-Proton Scattering at 1.48 BeV

Eisner, A.M. ; Hart, E.L. ; Louttit, R.I. ; et al.

Phys.Rev. 138 (1965) B670-B677, 1965.

Inspire Record 944962 DOI 10.17182/hepdata.461

A sample of 2657 proton-proton scattering events at 1.48 BeV has been analyzed. The elastic cross section is 19.86 mb, and the elastic scattering is consistent with a simple opaque-disk optical model with R=0.91 F and 1−a=0.864. The dominant feature of the inelastic scattering is the production of the (3/2, 3/2) isobar. The reaction p+p→p+n+π+ is interpreted satisfactorily in terms of the one-pion-exchange model.

2 data tables

Table 1

No description provided.

Table 2

No description provided.

STUDY OF p p INTERACTIONS AT 28.5-BeV/c IN TWO AND FOUR PRONG FINAL STATES

Connolly, P.L. ; Ellis, W.E. ; Hough, Paul V.C. ; et al.

C671122-2, 1967.

Inspire Record 1100201 DOI 10.17182/hepdata.50281

None

1 data table

Table 1

'1'. '2'. '3'.

Two-Charged-Particle Final States from pi-+p Interactions at 2.7 GeVc

Miller, D.H. ; Gutay, L. ; Johnson, P.B. ; et al.

Phys.Rev. 153 (1967) 1423-1442, 1967.

Inspire Record 52271 DOI 10.17182/hepdata.26636

A total of 24 360 events having two charged particles in the final state from π−+p interactions at an incident π− momentum of 2.7 GeVc have been analyzed. The final states π−π+n and π−π0p are found to be dominated by rho-meson production, and in addition, significant N*(1238) production is seen. The partial cross sections for the dominant resonant channels are σ=(pρ−)=(1.3±0.2) mb, σ(nρ0)=(2.3±0.2) mb, and σ[π−N*+(→pπ0)]=(0.5±0.2) mb. The production of the ρ− and ρ0 and the decay of the ρ− agree very well with the predictions of an absorption-modified one-pion-exchange model. The production angular distributions of the ρ0 and ρ− follow an exponential of the form Ae+Bt. The results from a least-squares fit give B(ρ−)=9.32±0.08 (GeVc)−2, B(ρ0)=10.26±0.06 (GeVc)−2. A similar analysis for the elastic-scattering events gave B(el)=7.77±0.05 (GeVc)−2. The ρ0 decay distributions are asymmetric and they have been analyzed using a simple model which includes S−P-wave interference. No clear evidence is seen for a T=0, J=0 resonance at a mass near that of the ρ. The N*(1238) resonance production is found to be in agreement with the ρ-exchange model of Stodolsky and Sakurai. Indication of other resonance production with small cross section is seen, such as A1 and A2 production in the multiple missing neutral events. The masses and widths of the ρ0 and ρ− as a function of the four-momentum transfer squared to the nucleon have been determined.

1 data table

Table 1

No description provided.

Strange-particle production in {8-BeV/c} proton-proton interactions

Firebaugh, M. ; Ascoli, G. ; Goldwasser, E.L. ; et al.

Phys.Rev. 172 (1968) 1354-1369, 1968.

Inspire Record 53978 DOI 10.17182/hepdata.26501

A systematic survey of strange-particle final states produced by 8−BeVc protons was made in the BNL 80-in. hydrogen bubble chamber. Cross sections were measured for some 33 reactions. The ratio of the cross section for the KK¯ channels to the total strange-particle cross section was measured to be 0.12 and appears to be rising in this momentum region. The total cross section for strange-particle production is estimated as 1.8±0.2 mb. Comparison is made of the data with the predictions of the one-pion-exchange model, and at least partial agreement occurs for the K+pΛ and πKNΣ final states. The KpΣ states appear to contain N*(1924)→KΣ, and the πKNΛ states all include Y*(1385) production with the π+K0pΛ state also containing N*(1236) and K*(890) production. An examination of the five- and six-body K, Λ states indicates strong Y*(1385) and N*(1236) production. Finally, all final states containing a K and a Λ show a dependence on M(K,Λ) which is well parametrized by a Breit-Wigner shape with M0=1777 MeV and Γ=345 MeV. This behavior is interpreted as being consistent with one-pion exchange as the dominant mechanism for these reactions.

1 data table

Table 1

'1'. '2'.

K-minus-p interactions from 594 to 820 mev/c

Bertanza, L. ; Bigi, A. ; Carrara, R. ; et al.

Phys.Rev. 177 (1969) 2036-2047, 1969.

Inspire Record 55654 DOI 10.17182/hepdata.70773

K−−p interactions in the Columbia-BNL 30-in. hydrogen bubble chamber were studied at nine momenta from 594 to 820 MeVc. The results for elastic-scattering and zero-prong-plus-V0 events are presented here. Differential cross sections are given for the K−p, K¯0n, and Λπ0 final states. A fit to the K¯N channels was obtained which shows the effects of a 32− resonance at 1701 MeV. This energy is appreciably displaced from the peak in the inelastic cross section.

5 data tables

Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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High-Energy Inelastic e p Scattering at 6-Degrees and 10-Degrees

Bloom, Elliott D. ; Coward, D.H. ; DeStaebler, H.C. ; et al.

Phys.Rev.Lett. 23 (1969) 930-934, 1969.

Inspire Record 54874 DOI 10.17182/hepdata.21635

Cross sections for inelastic scattering of electrons from hydrogen were measured for incident energies from 7 to 17 GeV at scattering angles of 6° to 10° covering a range of squared four-momentum transfers up to 7.4 (GeV/c)2. For low center-of-mass energies of the final hadronic system the cross section shows prominent resonances at low momentum transfer and diminishes markedly at higher momentum transfer. For high excitations the cross section shows only a weak momentum-transfer dependence.

9 data tables

Table 1

Axis error includes +- 0.0/0.0 contribution (?////FROM UNCERTAINTY IN ELECTRON-DETECTION EFFICIENCY).

Table 2

Axis error includes +- 0.0/0.0 contribution (?////FROM UNCERTAINTY IN ELECTRON-DETECTION EFFICIENCY).

Table 3

Axis error includes +- 0.0/0.0 contribution (?////FROM UNCERTAINTY IN ELECTRON-DETECTION EFFICIENCY).