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Centrality-Dependent Modification of Jet-Production Rates in Deuteron-Gold Collisions at √sNN=200 GeV

Jet production rates are measured in p+p and d+Au collisions at √sNN=200 GeV recorded in 2008 with the PHENIX detector at the Relativistic Heavy Ion Collider. Jets are reconstructed using the R=0.3 anti-k_t algorithm from energy deposits in the electromagnetic calorimeter and charged tracks in multiwire proportional chambers, and the jet transverse momentum (p_T) spectra are corrected for the detector response. Spectra are reported for jets with 12<pT<50 GeV/c, within a pseudorapidity acceptance of |η|<0.3. The nuclear-modification factor (R_dAu) values for 0%–100% d+Au events are found to be consistent with unity, constraining the role of initial state effects on jet production. However, the centrality-selected RdAu values and central-to-peripheral ratios (R_CP) show large, pT-dependent deviations from unity, challenging the conventional models that relate hard-process rates and soft-particle production in collisions involving nuclei.

RHIC ; PHENIX, d+Au collision ; Jet ; 200 GeV ;

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