Reactions p p → p p and p p → n n were studied at the kinetic energy 230 MeV of incident p by using bubble chamber films. Total cross sections for both of the reactions were found to be 51.2 ± 1.6 mb and 9.1 ± 0.6 mb, respectively. Differential cross sections are well explained by the phenomenological theory given by Bryan and Phillips.
No description provided.
No description provided.
No description provided.
The p p → n n polarization has been measured at 8 GeV/ c and for − t values ranging from 0 up to 0.8 (GeV/ c ) 2 . A small and negative polarization has been found.
ERRORS INCLUDE STATISTICAL AS WELL AS RELATIVELY SMALL SYSTEMATIC EFFECTS.
The differential cross section for the charge exchange p p → n n has been measured with high statistics at 7.76 GeV/ c and at 5.0 GeV/ c . The 7.76 GeV/ c data show a very narrow [ Δt ⪅ 0.01 (GeV/ c ) 2 ] forward peak superposed on a slow exponential fall-off.
No description provided.
No description provided.
INTEGRATED CROSS SECTIONS FROM EXPONENTIAL FIT.
Cross sections for p ̄ p → n ̄ n at 25 and 35 GeV/ c have been measured. The cross sections decrease with increasing momentum as 1/ P 2 . A narrow peak is observed in the momentum transfer interval 0 ⩽ − t ≲ 0.02 (GeV/ c 2 in the differential cross sections. Neither ϱ nor A 2 exchange contribute to the process in the investigated energy range.
K- CEX MEASURED BY STARS FROM KL AS A CHECK.
No description provided.
No description provided.
The reaction p ̄ p → n ̄ n has been studied at an incident antiproton laboratory momentum of 1.13 GeV/ c . The antineutron was identified through a subsequent annihilation on a proton. In all, 2601 identified events were obtained. Total and differential cross sections are presented. Comparison is made with the predictions of the Bryan and Phillips model which, in this energy range, is succesful in describing the related reaction p ̄ p → p ̄ p . Here, the agreement is less good.
No description provided.
None
No description provided.
No description provided.
We have measured the reaction cross section for p¯p→n¯n in small momentum steps between 0.97 and 3.13 Gev/c to a high level of statistical accuracy. Structures are observed in the vicinity of Plab=1.25 GeVc and 1.8 GeVc which are consistent with the structure observed in the p¯p total cross section.
No description provided.
No definite evidence for structure is found in the p¯p→n¯n cross section between 276 and 963 MeV/c. From these results limits are deduced on properties of the narrow enhancement reported in the p¯p total cross section at 475 MeV/c.
No description provided.
Based on a sample of about 3500 events, we have measured the total and differential cross sections of p p → n n in the 700–760 MeV/ c incident momentum region. It is found that σ CE = 10.7 ± 0.2 mb at the average momentum of 730 MeV/ c . The differential angular distribution is characterised by a sharp peak and a dip in the forward direction followed by a secondary maximum. The position of the dip corresponds to | t | ≈ m π 2 . These results are compared with the predictions of the model of Bryan-Phillips. On the other hand, this dip-bump structure can be well understood on a simple picture involving a π exchange and a constant background (for | t | ≲ 3 m π 2 ).
No description provided.
No description provided.
No description provided.
Charge-exchange cross section for antiprotons on protons has been measured in closely spaced momentum intervals from 0.119 to 1.046 GeV/c. The regions of the reported resonances at 1936 and 2020 MeV were scanned in 10-MeV/c steps with a typical statistical error of ≈ 1% and an rms mass resolution of ± 1.5 MeV. No enhancements were observed.
ERROR ON INCIDENT MOMENTUM IS RMS RESOLUTION. LARGE UNCERTAINTIES EXIST IN THE MEAN INTERACTION MOMENTUM FOR THE TWO LOWEST MOMENTUM POINTS.