WIC is, in theory, sensitive to the 135.6-nm emission of OI, and to a lesser extent the 130.4 emission, a much brighter line. We have direct observations
of the OI 1356 line in SI-13, and comparable images of LBH etc. in WIC. The question is how much of OI does WIC see.

The OI emissions in question can be characterized as follows. Inasfar as relative brightnesses go, dayglow the 130.4 line is ~10 times brighter than 135.6 in the dayglow, though in the nightglow they are comparable (meier 1991, chakrabarti, 1984). On the nightside, on the other hand, the 1304 airglow is on the order of the 1356 emission or somewhat greater. However, a view through the limb could amplify 1356 by 2-3 times.  That is taken into consideration here, as the view from SI-13 is through the nightside equatorial limb.

In the aurora, 130.4 is again ~ 10 times brighter than 135.6.

For this work, it is assumed that the total 130.4-nm emission is equal in brightness to the total LBH emission in both the aurora and the airglow, and in the lab spectrum. This is probably an underestimate, but we use this for now.

--- Two Images ---

The images discussed below are in this figure.

The image s1320001331013 shows the dayglow, auroral emissions and equatorial airglow in the 135.6 nm line of OI.

The nightside aurora is nearly as bright as the dayside at S=~50. So the auroral emissions and dayside emissions are comparable.
So estimate 1kR of 1356, 10 kR of 1304 in the aurora on the nightside. This is a reasonable estimate.

The equatorial airglow is about 30 % as bright as the aurora, i.e. ~3kR in all. Normally the contributions of 1304 and 1356 are equal, but
in limb viewing, the majority of the emission is probably 1356,  call it 2 kR of 1356 and 1kR of 1304. Nadir views of the emissions would not be as bright.

The WIC image of the same time shows the very bright dayglow as well as bright auroral emissions.

If WIC had a flat, square response from 1304-1900, about 60% of the response to the dayglow or aurora,  would be to OI, 40% to LBH. And the nightside airglow bands would be evident.

Given the actual, or rather, suspected WIC passband, approximately 16% of the response would be due to OI.
(See accompanying calculation).

In the output of plot_equator, the peak-average auroral brightness of 1300 counts would correspond to ~210 counts due to OI emissions.

Given the ratio in the 135.6-nm image, WIC should see about 1/3 of  this in the equatorial airglow. That's 70 counts. It sees 12 counts.  Yes, that's low for WIC (right at the one photon level)! This is done with 5-point smoothing and removal of a constant bias of ~355 counts, which brings a single value of the cut to 0 counts. If a fit to the slow increase in brightness as one moves right in the image were made, and that trend removed, the count rate would be smaller yet.

--- Conclusion ---

The passband as reported by MSFC is ~6 times too great in the 130.4-135.6 range. The solution to this problem is not unique, since there are two emissions in the passband and different relative weightings could be imagined which achieved the same result. I simply apply this correction evenly from 1360 on down. My adjusted numbers for the wic sensitivity are then as follows.

wsens_wic=[120.0,122.0,124.0,126.0,128.0,130.0,132.0,134.0,136.0,138.0,140.0,$
 142.0,144.0,146.0,148.0,150.0,152.0,154.0,156.0,158.0,160.0,161.4,162.0, $
 164.0,166.0,168.0,170.0,172.0,174.0,176.0,178.0,180.0,182.0,184.0,186.0, $
 188.0,190.0,192.0,194.0,196.0,198.0,200.0,202.0,204.0,206.0,208.0,210.0, $
 212.0,214.0,216.0,218.0,220.0]*10.0

sens_wic=[0.000e+00,$
 0.000e+00, 0.000e+00, 0.000e+00, 0.000e+00, 1.112e-04,$
 3.833e-04, 3.117e-04, 2.900e-04, 2.510e-03, 3.350e-03,$
 3.970e-03, 6.790e-03, 1.190e-02, 1.740e-02, 2.100e-02,$
 2.010e-02, 1.740e-02, 1.590e-02, 1.680e-02, 1.690e-02,$
 1.580e-02, 1.410e-02, 1.030e-02, 7.560e-03, 7.890e-03,$
 8.150e-03, 9.210e-03, 6.240e-03, 6.330e-03, 7.020e-03,$
 5.700e-03, 4.280e-03, 2.840e-03, 2.080e-03, 1.100e-03,$
 8.140e-04, 3.860e-04, 3.090e-04, 2.530e-04, 2.970e-04,$
 1.550e-04, 1.790e-04, 2.460e-04, 7.200e-05, 1.380e-04,$
 1.940e-04, 1.650e-04, 8.340e-05, 1.770e-04, 1.370e-04,$
 8.860e-05]

I might be accused of a cheap hack on the nightside, subtracting the gain which suits me best, but again, I could have fit the data with a parabola and looked for the equatorial airglow above _that_. That probably makes the best sense, but this works for now. If you want to reduce the short-wavelength sensitivity by more, feel free.

Other areas for error,
1) assumption of 1304 brightness relative to LBH. ( I do not believe I overestimated that, at least).
2)  difference between lab LBH spectrum and one out in real world. (Existence of contaminating lines?)