HEPData Search

Transmission measurements in good and poor geometry have been performed at the Brookhaven Cosmotron to measure the total and absorption cross sections of several nuclei for neutrons in the Bev energy range. The neutrons are produced by bombarding a Be target with 2.2-Bev protons. The neutron detector requires the incident particle to pass an anticoincidence counter and produce in an aluminum radiator a charged particle that will traverse a fourfold scintillation telescope containing 6 in. of lead. Contribution of neutrons below 800 Mev are believed small. The angular distribution of neutrons from the target is sharply peaked forward with a half-width of 6°. The integral angular distributions of diffraction scattered neutrons from C, Cu, and Pb are measured by varying the detector geometry. The angular half-width of these distributions indicates a mean effective neutron energy of 1.4±0.2 Bev. The total cross sections σH and σD−σH are measured by attenuation differences in good geometry of CH2-C and D2O-H2O, with the result: σH=42.4±1.8 mb, σD−σH=42.2±1.8 mb. The cross sections of eight elements from Be to U are measured in good and poor geometry, and the following values of the total and absorption cross sections are deduced (in units of millibrans): Experimental errors are about 3 percent in σtotal and 5 percent in σabsorption. An interpretation of these cross sections is given in terms of optical model parameters for two extreme nuclear density distributions: uniform (radius R) and Gaussian [ρ=ρ0exp−(ra)2]. The absorption cross-section data are well fitted with R=1.28A13 or a=0.32+0.62A13 in units of 10−13 cm. A nuclear density distribution intermediate between uniform and Gaussian will make the present results consistent with the recent electromagnetic radii.

2 data tables

Table 1

'ALL'.

Table 2

No description provided.

Proton-Proton Interactions at 2.75 Bev

Block, M.M. ; Harth, E.M. ; Cocconi, V.T. ; et al.

Phys.Rev. 103 (1956) 1484-1489, 1956.

Inspire Record 945002 DOI 10.17182/hepdata.26908

212 interactions of 2.75-Bev protons have been observed in a hydrogen-filled diffusion cloud chamber. The data indicate an elastic cross section of 15 millibarns, with about 9 millibarns cross section for single pion production, 13 millibarns for double, and 4 for triple. There is one example of quadruple pion production. One definite example of the production of heavy unstable particles was observed, and two doubtful cases. The median elastic scattering angle was 19° in the c.m. system. Angle and momentum distributions for inelastic events are consistent with those observed at lower energies.

1 data table

Table 1

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

Total Cross Sections for p, \bar{p}, K + /-, and pi + /- on Hydrogen Between 3 and 10 Gev/c

von Dardel, G. ; Frisch, D.H. ; Mermod, R. ; et al.

Phys.Rev.Lett. 5 (1960) 333-336, 1960.

Inspire Record 944910 DOI 10.17182/hepdata.197

None

2 data tables

Table 1

No description provided.

Table 2

No description provided.

Total Cross Sections of Protons with Momentum Between 10 and 28 Gev/c

Ashmore, A. ; Cocconi, G. ; Diddens, A.N. ; et al.

Phys.Rev.Lett. 5 (1960) 576-578, 1960.

Inspire Record 944909 DOI 10.17182/hepdata.192

None

2 data tables

Table 1

No description provided.

Table 2

No description provided.

High-Energy Proton Scattering from Carbon and Deuterium

Cocconi, G. ; Diddens, A.N. ; Lillethun, E. ; et al.

Phys.Rev. 126 (1962) 277-278, 1962.

Inspire Record 944981 DOI 10.17182/hepdata.26781

The momentum spectra of protons scattered from carbon and deuterium at angles close to 60 mrad and for incident proton momenta between 12 and 27 Gev/c have been measured. The data show good agreement with calculations based on plural quasi-elastic proton-nucleon scattering within the nucleus.

2 data tables

Table 1

No description provided.

Table 2

No description provided.

Polarization of the Recoil Proton from the Neutral Photoproduction at 800 and 910 Mev

Mencuccini, C. ; Querzoli, R. ; Salvini, G. ;

Phys.Rev. 126 (1962) 1181-1182, 1962.

Inspire Record 944983 DOI 10.17182/hepdata.26790

The measurements on the polarization of the recoil protons from the process γ+p→π0+p have been extended to higher γ-ray energies, at 90° in the center-of-mass system. We have found at 910 Mev a polarization, P=−0.45±0.07; at 800 Mev, P=−0.42±0.10. The rather high values of P agree with the hypothesis that the neutral photoproduction in the 500-1000 Mev range can be described by the well-known three resonant states, and strongly indicate that the second and third resonance have opposite parity. The probable quantum numbers are: T=12, J=32, D pion wave for the second resonance; T=12, J=52, F wave for the third resonance.

1 data table

Table 1

No description provided.