If this is the current waveform from an electronic ballast it is not a very good ballast. It is important the waveform be symmetrical to avoid mercury alloyed plating forming on one end of the bulb.
Many of the cheap battery operated flourescent light ballast have unsymmetrical waveforms. The bulb life is greatly shortened and you usually see a black plating spot on one end of the bulb.
Not knowing exactly what and how you are measuring it you might be corrupting the waveform with the ground side scope connection. If you are using a dual channel scope suggest you put it in differential mode and use the two probe tips to measure across the resistor.