The total cross section of slow neutrons on gaseous parahydrogen has been measured at several temperatures near 20 K and with pressures ranging from 250 to 750 Torr. A previous experiment had suggested that the cross section would exhibit a significant pressure dependence. However, no such pressure dependence was observed. The data give a value for the neutron-proton coherent scattering length of (-3.733±0.004) × 10-13 cm, in agreement with the latest liquid mirror measurements. NUCLEAR REACTIONS H1(n, n); E=4.2-4.6 meV; parahydrogen; measured total neutron cross section; deduced coherent scattering length.
All Science Journal Classification (ASJC) codes
- Nuclear and High Energy Physics