Proton-proton interactions at 5.3 BeV

Wright, Robert W. ; Saphir, George ; Powell, Wilson M. ; et al.
Phys.Rev. 100 (1955) 1802, 1955.
Inspire Record 1188071 DOI 10.17182/hepdata.26941

None

1 data table

No description provided.


p-p Interactions at 3 Bev

Cester, R. ; Hoang, T.F. ; Kernan, A. ;
Phys.Rev. 103 (1956) 1443-1449, 1956.
Inspire Record 945004 DOI 10.17182/hepdata.26958

Interactions initiated by 3-Bev protons of the Brookhaven Cosmotron were studied by photoemulsion technique. With appropriate criteria, 115 events are attributed to interactions of the incident beam protons with hydrogen nuclei (∼55%) and with bound protons of other nuclei (∼45%). A detailed analysis allowed the subdivision of the 115 events in categories, according to the number of π mesons (N>~0) produced in the collision. The ratio of elastic scattering to the total number of events was estimated to be σelσtotal=0.20−0.07+0.04. The observed cross section for pure elastic scattering is σel=8.9±1.0 mb. The percentages of single, double, triple, and quadruple π-meson production are respectively: 34−20+22; 35.6−23+20; 9.6−4+6; ∼1.0+3.5. Among the 20 most probable cases of single π-meson production—the estimated ratio of π+ to π0 is σπ+σπ0=5.3−1.4+0.3. The experimental results are not in agreement with the Fermi statistical-model theory (in particular the lower limit for the experimental ratio of triple to single production is given by σ3σ1>∼110 in contrast with the predicted ratio σ3σ1=167) but are not inconsistent with the Peaslee excited-state-model theory.

1 data table

No description provided.


Elastic Proton-Proton Scattering at 2.24, 4.40, and 6.15 Bev

Cork, Bruce ; Wenzel, William A. ; Causey, Charles W. ;
Phys.Rev. 107 (1957) 859-867, 1957.
Inspire Record 944998 DOI 10.17182/hepdata.26883

Protons of the internal circulating beam of the Bevatron were scattered in a polyethylene target. Both scattered and recoil protons were detected by scintillation counters at angles which define elastic proton-proton events. An internal counter was located within a few inches of the beam to permit measurements at laboratory scattering angles as low as 2°. Absolute values are based on the calibration of the induction electrode that monitors the circulating beam. Total elastic cross sections obtained by integrating the differential spectra are 17, 10, and 8 mb at 2.24, 4.40, and 6.15 Bev, respectively. The experimental angular distributions are consistent with the prediction of a simple optical model with a complex index of refraction at short range.

1 data table

'ALL'.


Elastic Scattering and Single Meson Production in Proton-Proton Collisions at 2.85 Bev

Smith, G.A. ; Courant, H. ; Fowler, E.C. ; et al.
Phys.Rev. 123 (1961) 2160-2167, 1961.
Inspire Record 47571 DOI 10.17182/hepdata.734

The Brookhaven National Laboratory twenty-inch liquid hydrogen bubble chamber was exposed to a monoenergetic beam of 2.85-Bev protons, elastically scattered from a carbon target in the internal beam of the Cosmotron. All two-prong events, excluding strange particle events, have been studied by the Yale High-Energy Group. The remaining interactions have been studied by the Brookhaven Bubble Chamber Group. Elastic scattering was found to be mostly pure diffraction scattering at center-of-mass angles up to about thirty-five degrees. Some phase shift and/or tapering of the proton edge was required to fit the data at larger angles. No polarization effects in the proton-carbon scattering were observed using hydrogen as an analyzer of polarized protons. Nucleonic isobar formation in the T=32, J=32 state was found to account for a large part of single pion production. High-orbital angular-momentum states were found to be greatly favored in single pion production. The isobar model of Lindenbaum and Sternheimer gave good agreement with the observed nucleon and pion energy spectra. No polarization or alignment effects were observed for the isobar assumed in this model.

3 data tables

No description provided.

No description provided.


Proton-Proton Collisions at 4.2 Bev

Blue, M.H. ; Lord, J.J. ; Parks, J.G. ; et al.
Phys.Rev. 125 (1962) 1386-1393, 1962.
Inspire Record 944984 DOI 10.17182/hepdata.26806

Interactions between 4.15-Bev protons and the free hydrogen nuclei in nuclear emulsion are examined. The total elastic cross section from 27 events was determined to be 11.0±2.6 mb. On the basis of 113 interactions the total inelastic cross section was found to be 28.1±3.1 mb. The partial cross sections corresponding to inelastic collisions having two, four, six, and eight secondary particles were found to be respectively 16.3±2.4, 11.5±1.8, 0.2±0.1, and 0.1±0.1 mb. While the total inelastic cross section varies slowly with energy, the partial inelastic cross sections were found to be strongly energy dependent. The observed angular distribution of elastically scattered protons in the center-of-mass system was sharply peaked in the forward and backward directions, in fair agreement with calculations based on a simple optical model applicable for energies between 2 and 10 Bev. Particles produced in inelastic collisions were identified as pions or protons by measurements of energy loss and multiple scattering. For those particles identified, center-of-mass system distributions of energy, angle, and transverse momentum are presented.

1 data table

'ALL'.


p-p Interactions at 2 Bev. 2. Multiple-Pion Production

Pickup, E. ; Robinson, D.K. ; Salant, E.O. ;
Phys.Rev. 125 (1962) 2091-2101, 1962.
Inspire Record 47226 DOI 10.17182/hepdata.26793

Analyses have been made for 871 four-prong events and 463 two-prong events corresponding to multiple pion production, resulting from p−p interactions at 2 Bev in the BNL 20-in. hydrogen bubble chamber. Cross sections have been obtained for all the observable double and triple pion production processes; the branching ratios predicted by the extended isobar model are shown to be in fair agreement with the data, but there are significant differences. The c.m. momentum distributions are also in fair agreement with the predictions of the model, although there are ambiguities in the interpretation. The pion-nucleon Q values give clear evidence for the importance of the (32, 32) resonant state in multiple pion production, but consideration of this state alone does not provide an explanation of the features of double pion production. Some contribution from another state, possibly the I=12 nucleon isobar, is necessary. In double production, the c.m. angular distributions of the nucleons show backward-forward peaking suggestive of a one-pion exchange process. The angular distributions of the nucleons from triple production are almost isotropic.

1 data table

No description provided.


p-p Interactions at 2 Bev. 1. Single-Pion Production

Fickinger, W.J. ; Pickup, E. ; Robinson, D.K. ; et al.
Phys.Rev. 125 (1962) 2082-2090, 1962.
Inspire Record 46669 DOI 10.17182/hepdata.26851

3600 two-pronged events, obtained in p−p interactions at 2 Bev in the BNL 20-in. hydrogen bubble chamber, have been analyzed. Cross sections have been measured for elastic scattering, for the two modes of single-pion production, p+p→p+n+π+, p+p→p+p+π0, and for strange-particle production. The branching ratio for the two one-pion production reactions is σ(pnπ+)σ(ppπ0)=4.17±0.25. Momentum distributions and Q values indicate that single-pion production proceeds almost entirely through the (32, 32) resonant state. The data have been considered in terms of the extended isobar model and also a one-pion exchange model for production. The branching ratio and momentum distributions can be explained by including a small effect from the I=12 resonant state in addition to the dominant I=32 resonance. The c.m. angular distribution of the nucleons in single-pion production shows very marked backward-forward peaking indicating a one-pion exchange mechanism. Absolute differential cross sections as a function of laboratory kinetic energy have been calculated from Selleri's equation for the pnπ+ reaction. There is good agreement with the data for low four-momentum transfers [q2<0.15(Bev/c)2], but for higher momentum transfers the theoretical cross sections are larger than the experimental cross sections.

1 data table

No description provided.


High-Energy Nucleon-Nucleon total Cross Sections

Diddens, A.N. ; Lillethun, E. ; Manning, G. ; et al.
Phys.Rev.Lett. 9 (1962) 32-34, 1962.
Inspire Record 944903 DOI 10.17182/hepdata.46

None

3 data tables

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

No description provided.

No description provided.


High-Energy Proton-Proton Diffraction Scattering

Diddens, A.N. ; Lillethun, E. ; Manning, G. ; et al.
Phys.Rev.Lett. 9 (1962) 108-111, 1962.
Inspire Record 46802 DOI 10.17182/hepdata.21634

None

7 data tables

This table from the from the Erratum.

Table 1.

Table 2.

More…

High-Energy Proton-Proton Scattering

Diddens, A.N. ; Lillethun, E. ; Manning, G. ; et al.
Phys.Rev.Lett. 9 (1962) 111-114, 1962.
Inspire Record 46897 DOI 10.17182/hepdata.19387

None

1 data table