1. Telescope Array Experiment: Status and Prospects Pierre Sokolsky University of Utah

2. Cosmic Ray Spectrum

3. 5σ Observation of the GZK Suppression (mono)

4. HiRes/Auger spectra comparison Auger confirms all spectral features of HiRes spectrum

5. UHECR Status and Issues GZK cutoff exists – HiRes and PAO observe at 5-6 sigma level Anisotropy ( sources ) remain unclear- 2-3 sigma correlation in South with AGN’s (PAO), no correlations in North (HiRes). Composition – light (proton) favored by HiRes. Light- heavy-light(?) favored by PAO >>> A lot more work is required >>> Unravelling galactic/extragalactic transition

6. Motivation for TA AGASA and HiRes give conflicting results on GZK. Why? Increase SD by 10 x. Coincident event observation with FD. Keep AGASA and HiRes energy scales Hybrid events > calibrate SD SD 10 x higher statistics than HiRes

27. Motivation for TALE Sources of cosmic rays above knee (1015 eV) are unknown. What is the Emax of the galactic accelerator? Connect energy scale established by GZK to all the other structures in the cr spectrum ( ankle, second knee etc.) Study the composition change from galactic to extragalactic cosmic rays.

30. TALE Proposal under consideration by PASAG

31. Thank You !