The time evolution of uncontrolled amplifier gain transients due to dropped or cut dense-wavelength-division multiplexed channels in a broadband all-Raman amplified recirculating loop experiment is measured for different surviving channel wavelength configurations with propagation up to 7200 km. Different time signatures develop depending on whether the surviving channels are located at the long-or short-wavelength end of the spectrum. Channel power tilt and gain error within a surviving

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... group can vary with distance and are shown to correlate with growth of amplified spontaneous emission noise at the dropped channel wavelengths.