M. Derrick et al., OBSERVATION OF EVENTS WITH AN ENERGETIC FORWARD NEUTRON IN DEEP-INELASTIC SCATTERING AT HERA, Physics letters. Section B, 384(1-4), 1996, pp. 388-400
In deep inelastic neutral current scattering of positrons acid protons
at the center of mass energy of 300 GeV, we observe, with the ZEUS de
tector, events with a high energy neutron produced at very small scatt
ering angles with respect to the proton direction. The events constitu
te a fixed fraction of the deep inelastic, neutral current event sampl
e independent of Bjorken x and Q(2) in the range 3 . 10(-4)<x(BJ)<6 .
10(-3) and 10<Q(2)<100 GeV2.