Imaging of Attosecond Ring Current Dynamics

When a helium atom is excited into a superposition of a $1s$ and a $np+$ state, the electron wave packet produces a ring current with attosecond scale charge density dynamics. We have studied the preparation and time dependent imaging of such a system utilizing attosecond laser pulses. The presented results are obtained from {\it ab initio} simulations of the time dependent Schr\"{o}dinger equation in the single active electron and dipole approximations. Effects of pulse length, polarization and other parameters of the imaging pulse on the obtained data will be discussed.