Profile data is availaible here: Z(#4)

This subsection is heavily paraphrased from the UKIDSS website, technical section - filters.

The bandpass of the WFCAM Z filter (0.83-0.925µm) was designed to provide a reasonable match to the effective wavelength of the SDSS z' bandpass, but with a rectangular profile, and avoiding the atmospheric absorption band near 0.95µm. The two bandpasses are compared in Figure 2.4, “UKIDSS WFCAM Z filter profile”. The specified WFCAM Z profile is shown in red. The array quantum efficiency is approximately flat over this wavelength range. The SDSS z' bandpass is defined by the long-pass z' filter and the falling q.e. of the CCDs towards longer wavelengths, multiplied by the atmospheric transmission. The normalised z' system throughput is shown as the grey dash-dot line. The effective wavelengths of the WFCAM Z and SDSS z' bandpasses are 0.876µm and 0.887µm, respectively (effective wavelength as defined by Schneider et al. (1993) ApJ, 264, 337).