The noise on the SW channel has several origins: detector noise, amplifier noise, electric cross talk, and peak up noise.
The output signal is very small, a few mV, and the lines are very easily affected by peak up noise. To reduce the effect of the peak up noise, the signals from the 2 blind lines go through the electronic chain as if they were pixel lines. They are used as a reference for the correlated peak up noise. A correlation matrix between the pixels on the reference lines and the actual pixels must be used to remove the correlated noise.
Cross talk between pixels takes place in the connecting wires between the array and the cold electronic. Since odd and even lines have geometrically separated outputs, the cross talk has a strong parity characteristic. Echoes of a bright sources on line n is found on lines n-2 and n+2, and not on lines n-1 and n+1. A cross talk matrix must be used to remove the cross talk.
Both the correlated noise and the cross talk matrices have been measured during ground calibration. They can hardly be redetermined in flight, but a few points can be verified. They will be provided to the observer together with the standard data products.
After removal of the correlated noise, and of the cross talk, the
remaining noise can be very well modelled by a constant readout
noise and the photon shot noise. The readout noise is about 700
/px rms.
The Flight Model array has 4 low responsivity pixels, all close to
the sides of the array (Showing in black on Figure 
).