A MEASUREMENT OF THE ANGULAR RESOLUTION OF AIR SHOWERS A USING THE MUONIC COMPONENT AT GROUND LEVEL

The angular resolution of cosmic ray air showers is found to be 13.4 mr using single tracks and as good as 2 to 4 mr from all of the tracks for selected events by using the muonic component of air showers and a fine grained calorimeter. The sample of events was 8776 events triggered by an air shower array in which 3 to 76 muons were reconstructed. There was very little dependence of the single track angular resolution on either the number of muons or the shower angle.