Relativistic Heavy Ions

Experiment IV

Photons and Neutral Mesons

Time Evolution of a Heavy Ion Collision

Photon Sources in A+A Collisions

Hard direct Photons

E.M. Bremsstrahlung

Prompt Photon Sources in p+p Reactions

Prompt Photons

Photons fromJet-Fragmentation

Fraction of Prompt Photons in p+p Reactions

Photon Spectrum in p+p

Photons in p+p and p+A

Thermal photons fromthe hot medium

Jet-photon conversionin the medium

Additional Photon Sources in A+A

Turbide, Rapp, Gale, Phys. Rev. C 69 (014903), 2004

Theoretical Expectation in A+A

Rear View of Leadglass Block (Super Module)

Lead Glass Calorimeter in WA98

Electromagnetic Calorimeter in PHENIX

PHENIX Experiment

Photons from Radiative Decays in Pb+Pb at 158AGeV

Background Photons from Radiative Decays

Systematic Errors of Direct Photon Measurement in Pb+Pb

Ratio of Measured to Background Photons

Direct Photon Spectrum in Pb+Pb at 158AGeV

kt-broadening +Ti = 205MeV

no kt-broadening +Ti = 270MeV

Turbide, Rapp, Gale, Phys. Rev. C 69 (014902), 2004

Prompt and Thermal Photons in Pb+Pb at 158AGeV

Ti = 214 - 255 MeVQGP + HG + pQCD(Non-boost inv. hydro)

Huovinen, Ruuskanen, Räsänen (Nucl. Phys. A 650 (227) 1999)

Ti = 213 - 234 MeVPure HG + pQCD(Non-boost inv. hydro)

Ti = 335 MeV, = 0,2 fm/c

QGP + HG + pQCC(Bjorken hydro)

Svrivastava (nucl-th/0411041)

250 < Ti < 370 MeV,0,5 < < 3 fm/c

QGP + HG + pQCDRenk (Phys.Rev.C67:064901,2003)

Ti = 250 - 270 MeV, = 0,5 fm/c

QGP + HG + pQCD without kT

Ti = 205 MeV, = 1 fm/c

QGP + HG + pQCD with kT

Turbide, Rapp, Gale (Phys.Rev.C69:014903,2004 )

Theoretical Descriptions and Initial Temperatures Ti

p+p measurementscaled with Ncoll

Prompt Photons in Au+Au, s = 200GeV

Direct Photon Measurement via Virtual Photons

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Direct Photon Measurement via Virtual Photons

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Direct Photon Measurement via Virtual Photons

Direct Photon Measurement via Virtual Photons

Direct Photon Measurement via Virtual Photons