Tomography%20of%20High-Energy%20Nuclear%20Collisions%20with%20Photon-Hadron%20Correlations

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Tomography of High-Energy Nuclear Collisions with
Photon-Hadron Correlations
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Hanzhong Zhang, J. F. Owens, Enke Wang and X.-N.
Wang , Phys. Rev. Lett. 98, 212301
(2007) Phys. Rev. Lett. 103, 032302 (2009)
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?????????????QGP
Computed Tomography (CT)
RHIC/LHC--QGP
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Jet quenching (Jet energy loss)
X.-N.Wang and M.Gyulassy, Phys.Rev.Lett.68,1480(1
992)
??????????QGP????,???QGP???? ???????,??????,????(?
QGP??? ??????)?
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Single jet Dijet
Gamma-jet
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Single and di-jet ?????,????
Hanzhong Zhang, J. Owens, EnkeWang and X. N.
Wang, Phys. Rev. Lett. 98(2007)212301
Dihadron
Single Hadron
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NLO pQCD ???????? Gamma-Jet
LO (tree level)
NLO corrections (e.g. 2?3)
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Energy loss parameter
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Enke Wang , X. -N. Wang , PRL87(2001)142301)
Hanzhong Zhang, J. Owens, Enke Wang and X. N.
Wang, J. Phys. G., 34(2007)S801
dihadron
single hadron
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????????
The per-trigger photon-hadron spectra
D_AA (z_T)??????????????????????????????????. Some
times we call D_AA as the photon-triggered hadron
fragmentation functions
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Hanzhong Zhang, J. F. Owens, E. Wang and X.-N.
Wang , Phys. Rev. Lett. 103 032302, 2009 Eur.
Phys. J. C61 825-828, 2009.
pp

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• In pp ,NLO pQCD ?????,??????????,???????????????
• In AuAu,?????????????????

AuAu
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z_T????? --- ???????
??????????? ??,???????, ???????z_T?? ??? ?
?????(???)????, z_T?????,??????????????? ?????????
?,???????????QGP??
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z_T????? --- ???????
?????????? ??,???????? ??,???????? ?z_T????? ?
?z_T?????,??????????????? ???QGP??,??????????????
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??? ???????????????????QGP?????,??????????????
QGP????. ??????????,??QGP???????,??,??????qhat
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Thank for your attention!
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The fragmentation of the jets off the dense matter
medium
vacuum
(X. -N. Wang , PRC70(2004)031901)
The jet energy loss in a 1D expanding system
Energy loss parameter
(a parameterization form of theory calculations)
Enke Wang , X. -N. Wang , PRL87(2001)142301)
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NLO results for prompt photons in pp
Data with IC
PHENIX, PRL 98 (2007) 012002
the measured photon samples are expected to be
isolated from parton jet activity.
Because of IC selected at RHIC, most
fragmentation contributions from parton jets are
taken out.