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Hydrogen and deuterium gases have been bombarded in a gas target at a temperature of 77°K and at a pressure of about 140 atmospheres by the 318±10 Mev "spread-out" bremsstrahlung photon beam of the Berkeley electron synchrotron. The charged π-mesons which were produced were collimated at angles of 45°, 90°, and 135° to the beam direction. The π+ mesons were detected with trans-stilbene scintillation crystals using πμ, πβ, and πμβ delayed coincidences and π+ and π− mesons were detected with Ilford C-2 200-micron nuclear emulsions. The ratios of the numbers of π− to π+ mesons produced in deuterium were 0.96±0.10, 1.09±0.12, and 1.21±0.17 for the angles of 45°, 90°, and 135°, respectively. No variation of the ratio with meson energy, outside statistics, was observed. Absolute values for the π+ meson energy distribution functions from hydrogen and deuterium per "equivalent quantum" have been measured at each of the above production angles. The differential and total cross sections have been obtained by integrating over energy and angle, respectively. The experimental ratios of the deuterium to hydrogen cross sections are in good agreement with the phenomenological theory of Chew and Lewis when the Hulthén deuteron function with β=6α is used in the initial state, plane waves are used for the nucleons in the final state, and the bremsstrahlung cutoff is taken into account. The statistics of the data are, however, not sufficient to determine the amount of spin interaction. The excitation functions for hydrogen and deuterium and points on the angular distribution curves in the center-of-mass system have been obtained. An upper limit of 0.08 of the charged π-meson cross section was obtained for μ-meson production from deuterium.

1 data table

Table 1

No description provided.

Production of $pi^0$ Mesons by gamma-Rays on Hydrogen

Silverman, A. ; Stearns, M. ;

Phys.Rev. 88 (1952) 1225-1230, 1952.

Inspire Record 944938 DOI 10.17182/hepdata.26460

The production of π∘ mesons in the reaction γ+p→π∘+p is investigated as a function of the incident γ-ray energy in the region from 200 Mev to 300 Mev. For the π∘ emitted at approximately 90° laboratory angle, the differential cross section can be represented by (dσπ∘dΩ)π2=C(K−145)1.9±0.4, where K= energy of incident γ-ray in Mev. The approximate threshold for the reaction is 145 Mev. The ratio of the cross section at 60° laboratory angle to that at 90° laboratory angle, for γ-rays between 250 Mev and 300 Mev, is 1.45±0.25.

1 data table

Table 1

No description provided.

Photoproduction of Neutral Mesons in Hydrogen at High Energies

Walker, R.L. ; Oakley, D.C. ; Tollestrup, A.V. ;

Phys.Rev. 89 (1953) 1301-1302, 1953.

Inspire Record 944936 DOI 10.17182/hepdata.26445

None

1 data table

Table 1

No description provided.

Positive Photomesons from Hydrogen at 0-degrees

Jarmie, Nelson ; Repp, Gordon W. ; White, R.Stephen ;

Phys.Rev. 91 (1953) 1023-1024, 1953.

Inspire Record 944935 DOI 10.17182/hepdata.26458

None

1 data table

Table 1

No description provided.

Scattering of 151- and 188-Mev Positive Pions by Protons

Homa, George ; Goldhaber, Gerson ; Lederman, Leon M. ;

Phys.Rev. 93 (1954) 554-561, 1954.

Inspire Record 944934 DOI 10.17182/hepdata.26417

A beam of ∼200-Mev π+ mesons was defined inside the vacuum chamber of the Nevis Cyclotron. Nuclear emulsions were exposed to a flux of about 104 mesons/cm2. The plates were scanned for pion-hydrogen scatterings and 103 such events were observed in two interaction energies, 151±7 Mev and 188±8 Mev. We obtain total cross sections of 152±31 and 159±34×10−27 cm2, respectively. The data suggest that the angular distribution changes from backwards peaked to almost symmetric over this energy interval. Our observations are not in agreement with the hypothesis of a P32-wave resonance in this energy region. The best fit to the combined results includes a D-wave contribution of -5.4°, although satisfactory agreement may be obtained with only S and P waves.

2 data tables

Table 1

Axis error includes +- 0.0/0.0 contribution (?////Due to flux, scanning efficiency, doubtful and background events, and thesmall uncertainty in the density of hydrogen in the emulsion).

Table 2

Axis error includes +- 0.0/0.0 contribution (?////Due to flux, scanning efficiency, doubtful and background events, and thesmall uncertainty in the density of hydrogen in the emulsion).

Photoproduction of pi+ Mesons from Hydrogen Near Threshold

Bernardini, G. ; Goldwasser, E.L. ;

Phys.Rev. 94 (1954) 729-729, 1954.

Inspire Record 944933 DOI 10.17182/hepdata.26455

None

3 data tables

Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

Photoproduction of Charged Pi Mesons from Hydrogen and Deuterium

Jenkins, T.L. ; Luckey, D. ; Palfrey, T.R. ; et al.

Phys.Rev. 95 (1954) 179-184, 1954.

Inspire Record 944932 DOI 10.17182/hepdata.26426

Photoproduction cross sections of charged pi mesons from hydrogen and deuterium have been measured as a function of meson angle at gamma-ray energies of 200, 235, and 265 Mev. The angular range extends from 30° to 180° in the laboratory system. Absolute cross sections have been determined. A least-squares fit of the measured cross sections has been made to the expression A+Bcosθ+Csin2θ, which assumes only S and P wave scattering. The coefficients so determined are qualitatively consistent with electric and magnetic dipole absorption together with the assumption of a resonant state of angular momentum 32 and of energy close to 300 Mev. Comparison with neutral meson production indicates some direct charged meson production in the P state.

2 data tables

Table 1

No description provided.

Table 2

No description provided.