Interstellar absorptions and shocked clouds towards the supernova remnant RX J0852.0-4622

We present the results from a survey of interstellar absorptions towards the supernova remnant (SNR) RX J0852.04622. The distribution of K?i absorbers along the distance of the background stars is indicative of a local region (d < 600?pc) strongly depopulated by K?i line-absorbing clouds. This fact is supported by the behaviour of the interstellar extinction. We find four high-velocity Ca?ii components with velocities of >100?km?s-1 towards three stars and we identify these with shocked clouds of the Vela SNR. We reveal and measure the acceleration of two shocked clouds on the approaching and receding sides of the Vela SNR along the same line of sight. The acceleration, velocity and Ca ii column density of the clouds are used to probe their parameters. The total hydrogen column density of both accelerating clouds is found to be similar (similar to 6 x 1017?cm-2), which indicates that there is possibly a significant number of small-sized clouds in the vicinity of the Vela SNR.