THE DEPENDENCE OF SPATIAL LOCATION AND SIZE OF NEUTRON FLUX ON THE MAXIMUM NEUTRON ENERGY

Oct 15, 2020, 3:20 PM
25m
Online

Online

Oral report Section 3. Modern nuclear physics methods and technologies. Section 3. Modern nuclear physics methods and technologies

Speaker

Dr Igor Meshkov (P.N. Lebedev Physical Institute of the Russian Academy of Sciences Moscow)

Description

The spatial distribution of neutrons with the maximum energies from 3.3 to 5.3
MeV was investigated using a two-coordinate 10B detector. The detector was
located at the 119 cm distance from the 1000 cm3 beryllium target at the output of
on electron accelerator based photoneutron source. Between the 10B detector and
the target the collimator of 3 cm diameter was located. The contribution of slow
neutrons was suppressed by 0.5 cm thickness cadmium filter. The 3He counter
behind the 10B detector was used to take into account the contribution of the
background of slow neutrons. From the kinematics of the 9Be (γ, n) γ, n) 8Be reaction it
follows that an increase in gamma-ray energy by 1 MeV entails an increase in
neutron energy by 0.9 MeV.
The maximum intensity of the neutron flux measured along the horizontal axis
shifts back relative to the direction of the primary electron beam with increasing
electron energy and, accordingly, with the maximum neutron energy, as shown in
Fig. 1. The position of the maximum intensity of neutrons distribution is associated
with a maximum of neutron energy in the flux. In addition, one may note that the
width of the neutron intensity distribution in the flux increases with increasing
maximum neutron energy. It is possible that these effects can be used to control the
maximum neutron energy in the stream at the output of the source collimator.

Primary author

Dr Igor Meshkov (P.N. Lebedev Physical Institute of the Russian Academy of Sciences Moscow)

Co-authors

Dr Stanislav Potashev (The Institute for Nuclear Research of the Russian Academy of Sciences) Dr Sergey Karaevsky (The Institute for Nuclear Research of the Russian Academy of Sciences) Mr Yury Burmistrov (The Institute for Nuclear Research of the Russian Academy of Sciences) Dr Gennady Solodukhov (The Institute for Nuclear Research of the Russian Academy of Sciences) Mr Vasily Ponomarev (The Institute for Nuclear Research of the Russian Academy of Sciences) Dr Aleksandr Drachev (The Institute for Nuclear Research of the Russian Academy of Sciences)

Presentation materials