The thermal time-of-flight spectrometer IN4 with the forward scattering detector

We report on the thermal time-of-flight instrument IN4 at the ILL, constructed keeping in mind the extension of accessible kinematic range by implementing small-angle coverage with a purpose-built forward-scattering detector. This detector has become operational recently. The time-resolution of this type of crystal monochromator time-of-flight instrument on a continuous source is briefly discussed. We conclude that IN4 with its forward scattering detector, and BRISP which is presently coming on line, form an interesting complementary pair of instruments, providing an extended (Q,ω)-range for the investigation of condensed matter.