  A new multiplex-type inelastic neutron scattering spectrometer, HOrizontally
Defocusing Analyzer Concurrent data Acquisition spectrometer (HODACA), was
recently developed and built at the C1-1 cold neutron beam port in JRR-3. The
spectrometer is suitable for dynamics measurements in the energy range of $-1$
meV $\lesssim \hbar \omega \lesssim$ 7 meV, catering to a broad array of
research fields in physics and material science. HODACA combines 24 detectors
and 132 pieces of analyzer crystals and has an estimated measurement efficiency
that is 70 times greater than the existing conventional triple-axis
spectrometer at the C1-1 beam port. The concept, design, specification, and
results of commissioning experiments are described.
