Neutron Time-of-Flight Spectrometer for Use with the Harwell 110-Inch Cyclotron

Abstract

A description is given of a neutron time-of-flight spectrometer used for energies up to 140 Mev. A 20-mμsec neutron pulse is obtained by electrostatic deflection of the internal proton beam of the cyclotron onto a thick aluminum target. By timing the neutrons over a 26-meter flight path an energy spread of 4.2% at 15 Mev is obtained rising to 14% at 140 Mev. The advantages of the technique and possible improvements are discussed.