31st International Seminar on Interaction of Neutrons with Nuclei: Fundamental Interactions & Neutrons, Nuclear Structure, Ultracold Neutrons, Related Topics (ISINN-31)

Monitoring Neutron Spectrum of Reactor IBR2 Using New Direct Beam Detection System at Small Angle Neutron Scattering Spectrometer (YuMO)

29 May 2025, 15:05

15m

Room V6 (4th floor)

Parallel session 3 Parallel Session 3: Neutron detection & Methodical aspects/Physics of ultracold neutrons

Speaker

Ahmed Elmekawy (JINR)

Description

The specific geometry of small angle neutron scattering spectrometer YuMO, a central
hole along the neutron beam direction through the two scattering detectors reaching to direct
beam detector (DBD) located at 35 meters from moderator [1-3]
DBD importance return to determine the transmittance of the sample as a function of
wavelength, due to peculiarities of normalization when the ratio between the scattering values
from the sample and the vanadium standard become close to each other. Additional information
about the procedure can be found in [1,2]. Also to monitor occurring changes at reactor power
on long term.
The new direct beam detector at YuMO is a proportional gas detector with solid state
Boron converter [4-8]. Here we present recording for IBR2 neutron spectrum with different
reactor power by processing empty beam spectrum on DBD, it was shown that the detector
works effectively. Also, comparison between new and old DBD detector showed that both are
stably working. However new DBD have higher efficiency.