Author/Authors :
Crevecoeur، نويسنده , , Roelof and de Schepper، نويسنده , , Ignatz and de Graaf، نويسنده , , Leo and Montfrooij، نويسنده , , Wouter and Svensson، نويسنده , , Eric and Carlile، نويسنده , , Colin، نويسنده ,
Abstract :
We show that the angular resolution Δφ and time resolution Δt of neutron time-of-flight spectrometers can be determined accurately by measuring the scattering spectrum of superfluid 4He at low temperature. The method is used to determine Δφ and Δt of the IRIS spectrometer at ISIS (UK), yielding the values (FWHM) Δφ=0.118 rad (6.8°) and Δt=212 μs, and to reinterpret the results of Blagoveshchenskii et al., showing that their measured linewidths for superfluid 4He can be ascribed solely to the effect of the angular resolution of their time-of-flight spectrometer.
