This error term is effected by

Error term	Relevant subsection
Atmospheric scintillation and thermal background fluctuations	9.3
Wavefront corrugations before and after the StS	5.3
Wavefront corrugations before FSU spatial filter	7.3
Refractive index of air and colour of correlated flux	12.3
Wavefront amplitude and phase fluctuations above M1	4.3
Effect of detector noise and photon shot noise	10.3
Internal vibration in the VLTI	8.3