06/Feb/2009 High pT Physics, PragueShinIchi Esumi, Univ. of Tsukuba1 Interplay between jet and v 2 ShinIchi Esumi Inst. of Physics, Univ. of Tsukuba measurements and simulations

06/Feb/2009 High pT Physics, PragueShinIchi Esumi, Univ. of Tsukuba2 RHIC 200GeVSPS 17GeVRHIC 62GeV PHENIX nucl-ex/ S.Kniege, ISMD 2007 jet pp Au Jet suppression modification with 2-particle  correlation

06/Feb/2009 High pT Physics, PragueShinIchi Esumi, Univ. of Tsukuba3 3<p T trig <4GeV/c & 1.0<p T asso <1.5GeV/c 20-60% STAR  =  associate -  trigger (rad) Jet modification and geometry (and v 2 ) QM08: STAR, PHENIX QM04: STAR Mach-cone shape depends on R.P. angle. Mach-cone is a source of of v 2

06/Feb/2009 High pT Physics, PragueShinIchi Esumi, Univ. of Tsukuba4  ASSO. -  TRIG. < 0  ASSO. -  TRIG. > 0 in-pl. out-of-pl.

06/Feb/2009 High pT Physics, PragueShinIchi Esumi, Univ. of Tsukuba5 (1) (2) (3) (4) (5) (6) (7) (8)(1) (2) (3) (4) (5) (6) (7) (8) shape(1) = f 1 (x) shape(2) = f 2 (x) shape(3) = f 3 (x) shape(4) = f 4 (x) shape(5) = f 5 (x) = f 4 (-x) shape(6) = f 6 (x) = f 3 (-x) shape(7) = f 7 (x) = f 2 (-x) shape(8) = f 8 (x) = f 1 (-x) (1) (2) (3) (4)(5) (6) (7) (8) trigger particle  ASSO  TRIG ) < 0  ASSO  TRIG ) > 0  ASSO  TRIG (rad) (1) (2) (3) (4) Simulation Study  ASSO  TRIG (rad) (5) (6) (7) (8)

06/Feb/2009 High pT Physics, PragueShinIchi Esumi, Univ. of Tsukuba6 Simulation (1) (2) (3) (4) (5) (6) (7) (8)(1) (2) (3) (4) (5) (6) (7) (8) in-plane (5)(4) (3)(6) (2)(7)(8)(1) two-particle correlation trigger angle selection among (1) - (8) regions  ASSO  TRIG (rad) * two different ways of mixing (top: r.p. random, bottom: r.p. aligned) * flow subtraction (two components flow+jet model, with inclusive flow measurement, with zyam-like normalization) in-planeout-of-plane

06/Feb/2009 High pT Physics, PragueShinIchi Esumi, Univ. of Tsukuba7 Simulation (5)(4) (3)(6) (2)(7)(8)(1) (4) + (5) (3) + (6) (2) + (7)(1) + (8) (1) (2) (3) (4) (5) (6) (7) (8)(1) (2) (3) (4) (5) (6) (7) (8) in-plane  ASSO  TRIG (rad) trigger angle selection among (1) - (8) regions top : left-right separated trigger w.r.t. R.P. bottom : left-right non-separated line : average of all (1) - (8) with experimental E.P. resolution ~0.7 in-planeout-of-plane flow-subtracted correlation

06/Feb/2009 High pT Physics, PragueShinIchi Esumi, Univ. of Tsukuba8 Simulation (5)(4) (3)(6) (2)(7)(8)(1) (4) + (5) (3) + (6) (2) + (7)(1) + (8) (1) (2) (3) (4) (5) (6) (7) (8)(1) (2) (3) (4) (5) (6) (7) (8) in-plane flow-subtracted correlation  ASSO  TRIG (rad) trigger angle selection among (1) - (8) regions in-planeout-of-plane top : left-right separated trigger w.r.t. R.P. bottom : left-right non-separated line : average of all (1) - (8) with true R.P. (resolution = 1.0)

06/Feb/2009 High pT Physics, PragueShinIchi Esumi, Univ. of Tsukuba9 Simulation in-planeout-of-plane flow-subtracted correlation  ASSO  TRIG (rad) no R.P. dependence on jet shape (This will be a pure non-flow.)

06/Feb/2009 High pT Physics, PragueShinIchi Esumi, Univ. of Tsukuba10 RHIC 200GeV Au+Au, mid-central collisions at mid-p T region (1-4 GeV/c) with v 2 = 0.1 ~ 0.2 * Significant semi-hard (mini-jet) fraction relative to soft-thermal contribution ~ several*10% * Significant v 2 effect from the semi-hard component relative to soft-thermal particle v 2 ~ several*10% * Significant smearing on jet shape even with  R.P. ~ 0.7 But it’s not really because of poor accuracy of E.P. angle, it’s more because mini-jets push up the inclusive v 2 which is subtracted. * RHIC data analysis is in progress… * E.P. can also be biased by correlated pair even with large  gap…

06/Feb/2009 High pT Physics, PragueShinIchi Esumi, Univ. of Tsukuba11 STAR Preliminary Ridge Jet 3<p T trig <4, 1.5<p T trig <2.0 GeV/c QM08 STAR STAR  (rad)  Ridge “jet” Au+Au, 200 GeV Ridge shape depends on R.P. angle. Ridge is a source of of v 2 Jet does not depends on it Jet reduces v 2  (rad)  PYTHIA p+p away side (in d  ) of one di-jet can be near side (in d  ) of another di-jet

06/Feb/2009 High pT Physics, PragueShinIchi Esumi, Univ. of Tsukuba12  (rad)  PYTHIA p+p trigger near side away side y x  (1)away side of a back-to-back(b-t-b) jet is wider in  than in  (2)If there are two parallel b-t-b jets, away side of one b-t-b jet can be near side of the another b-t-b jet. (3)Suppression as well as modification of b-t-b jet would depend on relative angle w.r.t. almond geometry, we know this from v 2 measurement and believe this is the major source of v 2 at high p T. (4)Therefore, there should be inter b-t-b jets correlation give by the geometry from (3), this could make near side ridge like effect, especially if the effect (3) has shaper dependence than v 2 (=cos2x). (5)We always measure inclusive v 2, which includes the effect (3). Therefore any modification which could generates the elliptic anisotropy would be included in the measured v 2. (6)We subtract BG contribution with this v 2 from (5) by maximizing BG contribution assuming zero jet yield at minimum at any d . (7)If near and away side jets overlap each other, this subtraction underestimates the jet yield and can change the extracted jet shape. (8)If you extract angular dependence of jet w.r.t. R.P., the results will easily be affected by the choice of v 2 from (5).