The Telescope Array Experiment: The Search for The Clusters in The Northern Hemisphere Sky with A Large Scintillator Array

In addition to the existence of extremely high energy cosmic rays (EHECRs) above GZK cutoff, the results of AGASA shows the clustering of EHECRs above 1019.6 eV. Confirming such clusters and identifying the corresponding astronomical object is crucial to understand the origin of EHECRs. The northern hemisphere sky is ideal for this purpose since the deflection by the galactic magnetic field is expected to be small and uniform compared to the southern hemisphere. In this paper, we report a design of the large ground array placed at the center of the hybrid-TA experiment. The array has an acceptance 9 times larger than AGASA. Using this detector, the cluster in the northern hemisphere will be searched with an angular resolution better than 1 degree