Parameters of the NERA spectrometer for cold and thermal moderators of the IBR-2 pulsed reactor

The inverted geometry time-of-flight spectrometer NERA designed for simultaneous investigation of elastic and inelastic neutron scattering was constructed on a 100 meter long flight path of the IBR-2 reactor at JINR, Dubna, Russia. Spectrometer parameters were optimized for the thermal neutron spectrum of a water moderator at 330 K. Recently, a new type of cold neutron source operating at 30 K was installed in the sector of six horizontal channels. The cold source in combination with the water moderator allows one to effectively use incident neutrons in wide range of wavelengths.