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Title: Azimuthal flow of decay photons in relativistic nuclear collisions

Journal Article · · Physical Review. C, Nuclear Physics
; ;  [1]
  1. Variable Energy Cyclotron Centre, 1/AF Bidhan Nagar, Kolkata 700 064 (India)

An overwhelming fraction of photons from relativistic heavy-ion collisions has its origin in the decay of {pi}{sup 0} and {eta} mesons. We calculate the azimuthal asymmetry of the decay photons for several azimuthally asymmetric pion distributions. We find that the k{sub T} dependence of the elliptic flow parameter v{sub 2} for the decay photons closely follows the elliptic flow parameter v{sub 2}{sup {pi}}{sup 0} evaluated at p{sub T}{approx_equal}k{sub T}+{delta}, where {delta}{approx_equal}0.1-0.2 GeV, for typical pion distributions measured in nucleus-nucleus collisions at relativistic energies. Similar results are obtained for photons from the 2-{gamma} decay of {eta} mesons. Assuming that the flow of {pi}{sup 0} is similar to those for {pi}{sup +} and {pi}{sup -} for which independent measurements would be generally available, this ansatz can help in identifying additional sources for photons. Taken along with quark number scaling suggested by the recombination model, it may help to estimate v{sub 2} of the parton distributions in terms of azimuthal asymmetry of the decay photons at large k{sub T}.

OSTI ID:
20863875
Journal Information:
Physical Review. C, Nuclear Physics, Vol. 74, Issue 4; Other Information: DOI: 10.1103/PhysRevC.74.044901; (c) 2006 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA); ISSN 0556-2813
Country of Publication:
United States
Language:
English