1. Relativistic Heavy Ions Experiment IV Photons and Neutral Mesons

2. Time Evolution of a Heavy Ion Collision

3. Photon Sources in A+A Collisions

4. Hard direct Photons E.M. Bremsstrahlung Prompt Photon Sources in p+p Reactions

5. Prompt Photons Photons from Jet-Fragmentation Fraction of Prompt Photons in p+p Reactions

6. Photon Spectrum in p+p

7. Photons in p+p and p+A

8. Thermal photons from the hot medium Jet-photon conversion in the medium Additional Photon Sources in A+A

9. Turbide, Rapp, Gale, Phys. Rev. C 69 (014903), 2004 Theoretical Expectation in A+A

11. Rear View of Leadglass Block (Super Module)

12. Lead Glass Calorimeter in WA98

13. Electromagnetic Calorimeter in PHENIX

14. PHENIX Experiment

26. Photons from Radiative Decays in Pb+Pb at 158AGeV

27. Background Photons from Radiative Decays

28. Systematic Errors of Direct Photon Measurement in Pb+Pb

29. Ratio of Measured to Background Photons

30. Direct Photon Spectrum in Pb+Pb at 158AGeV

31. k t -broadening + T i = 205MeV no k t -broadening + T i = 270MeV Turbide, Rapp, Gale, Phys. Rev. C 69 (014902), 2004 Prompt and Thermal Photons in Pb+Pb at 158AGeV

32. T i = 214 - 255 MeV QGP + HG + pQCD (Non-boost inv. hydro) Huovinen, Ruuskanen, Räsänen (Nucl. Phys. A 650 (227) 1999) T i = 213 - 234 MeV Pure HG + pQCD (Non-boost inv. hydro) T i = 335 MeV,   = 0,2 fm/c QGP + HG + pQCC (Bjorken hydro) Svrivastava (nucl-th/0411041) 250 < T i < 370 MeV, 0,5 <   < 3 fm/c QGP + HG + pQCDRenk (Phys.Rev.C67:064901,2003) T i = 250 - 270 MeV,   = 0,5 fm/c QGP + HG + pQCD without k T T i = 205 MeV,   = 1 fm/c QGP + HG + pQCD with k T Turbide, Rapp, Gale (Phys.Rev.C69:014903,2004 ) Theoretical Descriptions and Initial Temperatures T i

33. p+p measurement scaled with N coll Prompt Photons in Au+Au,  s = 200GeV

34. Direct Photon Measurement via Virtual Photons phase space factor form factor invariant mass of Dalitz pair invariant mass of virtual photon Compton q  g q e+e+ e-e- 00 e+e+ e-e-  

35.    S/B=~1    Direct Photon Measurement via Virtual Photons

36.    S/B=~1    calculated from Dalitz formula measured R data ÷ RR RR R direct measured with EMCal Direct Photon Measurement via Virtual Photons