a, Background-corrected intensity along the (1/2, 0, -1 - l) and (h, 0, -1 - h) directions. A δℏω = 0.25 meV running average was applied to each constant wavevector scan, retaining the actual point density of the acquired data. Black line, previously determined single-magnon dispersion5. White lines, bounds of two-magnon continuum calculated from this dispersion. Red circle with cross, the point where the single-particle dispersion relation intersects the lower bound of the two-particle continuum. b, First frequency moment of measured scattering intensity integrated over different energy ranges. Red squares (total), 0.8 ≤ ℏω ≤ 5.5 meV; black circles (quasiparticle), 0.8 ≤ ℏω ≤ 3 meV; blue diamonds (continuum), 3 ≤ ℏω ≤ 5.5 meV. c, Resolution-corrected half-width at half-maximum (HWHM) of the lower energy peak throughout the range of wavevector transfer for high resolution (solid points) and low resolution (open points) data. Error bars illustrate systematic error corresponding to 10% uncertainty in the neutron beam collimation used for resolution correction.