Echoes of Crab Pulsar Giant Radio Pulses

Occasional anomalous scattering of the Crab nebula pulsar radio pulses has been attributed to refraction from nebular plasma passing near the line of sight to the star. The scattered emission has been termed a pulse “echo” or “ghost”. We present here two days of high time resolution observations of individual giant radio pulses taken using the Very Large Array. The observations reveal echo emission at shorter time lags than has been seen before. An analysis of the characteristics of our echo component leads us to believe this phenomenon to be of a different nature than previously reported echo events.