Acoustic emission or crackling noise is measured from an experiment on splitting or peeling of paper. The energy of the events follows a power-law, with an exponent β ∼ 1.8 ± 0.2. The event intervals have a wide range, but superposed on scale-free statistics there is a time-scale, related to the typical spatial scale of the microstructure (a bond between two fibers). Since the peeling takes place via steady-state crack propagation, correlations can be studied with ease and shown to exist in the series of acoustic events.

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