1. The Transient Universe: AY 250 Spring 2007 New High Energy Telescopes Geoff Bower

2. The Transient Universe: AY 250 Spring 2007 EGRET Instrument on CGRO –NASA Great Observatory 20 MeV – 30 GeV 1500 cm^2 5 arcmin for strong sources

3. The Transient Universe: AY 250 Spring 2007 EGRET

4. The Transient Universe: AY 250 Spring 2007 Hartman et al 1999 271 sources 66 blazars 5 pulsars 170 unidentified

5. The Transient Universe: AY 250 Spring 2007 EGRET Blazars Mattox et al 1997

6. The Transient Universe: AY 250 Spring 2007 Compact & Flat Spectrum

7. The Transient Universe: AY 250 Spring 2007 Compact

8. The Transient Universe: AY 250 Spring 2007 Variable Mukherjee et al 1997

9. The Transient Universe: AY 250 Spring 2007 3C 279 Wehrle et al 1997

10. The Transient Universe: AY 250 Spring 2007 Ubertini 2007

11. The Transient Universe: AY 250 Spring 2007 Dominant in Energy

12. The Transient Universe: AY 250 Spring 2007 Extragalactic Background EGRB Narumoto & Totani 2006

13. The Transient Universe: AY 250 Spring 2007 GLAST

14. The Transient Universe: AY 250 Spring 2007

15. Michelson 2007

16. The Transient Universe: AY 250 Spring 2007

24. Padovani 2007

25. The Transient Universe: AY 250 Spring 2007 MAGIC result

26. The Transient Universe: AY 250 Spring 2007

27. HESS Atmospheric Cherenkov detector array 100 m^2 collecting area 5 deg FOV 0.16 deg resolution

28. The Transient Universe: AY 250 Spring 2007 HESS Camera 960 PMT pixels

29. The Transient Universe: AY 250 Spring 2007

32. Imaging Rejection of Cosmic Rays

33. The Transient Universe: AY 250 Spring 2007 Stereoscopic Vision

34. The Transient Universe: AY 250 Spring 2007 Cherenkov Basics Energy Range –1 TeV photon produces 100 photons/m^2 on the ground –Sensitivity set by ability to reject cosmic rays Effective Collecting Area –Not 4 x 100 m^2 –But 50,000 m^2 Light pool area (250 m diameter) Stereo vision –To reconstruct signal direction, reject cosmic rays

35. The Transient Universe: AY 250 Spring 2007 Cosmic Ray Discrimination