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Double entry plot extracted from the analytical formulae [1]. The green lines are the IN5B resolutions vs the chopper velocity (X-axis) and the wavelength (Y-axis).
The white lines define regions with different frame overlap ratio (a region where N=3 means that we need to spin the frame overlap chopper 3 times slower - 2 neutron pulses over 3 lost - than the other choppers to avoid frame overlaping) according to the rule λ_max = 1.5 λ_o where λ_o is the incident wavelength. The numbers stands for the frame overlap ratio.

As an example, a wavelength of 5 Å and a chopper velocity of 8500rpm give a resolution of 100 µeV with a frame overlap ratio of 3 (as we are close from the boundary a ratio of 2 might be also correct).

The color scale superimposes the measured absolute flux with the above calculated figure. It combines with the measured flux (see below).

The figure 2 shows the absolute flux as measured by gold foil activation for one velocity, 8500 rpm, i.e. half the maximal velocity, for a frame overlap ratio of 1 (same velocity for all the choppers). Doubling this velocity leads to a loss of flux by a factor 2.

The neutron intensity (here the neutron current I[n/cm2/s]) depends on the incident flux, the chopper velocities and the frame overlap ratio: 

Φ_Oλ [n/cm²/s] is the absolute flux per wavelength (unknown), N is the frame overlap ratio (see Fig. 1 above) and ω is the master chopper velocity.
With I_Oλ coming from Fig. 2 above, we have then: