Maki KUROSAWA for PHENIX collaboration

1. Higher harmonics flow measurement of charged hadrons and electrons in wide kinematic range withPHENIX VTX tracker Maki KUROSAWA for PHENIX collaboration QM2012 Washington 13-18 Aug

2. Outline of the Talk • Introduction • Method of Azimuthal anisotropy Measurements • Charged Hadron v2 and v3 in AuAu 200 GeV • Transvers momentum and h dependence. • Heavy Flavor Decomposition • First Measurements of Charm v2 • Summary QM2012 Washington 13-18 Aug

3. 1. Introduction • Physics motivation to measure heavy flavor • Initial state of QGP. • Detail study of QGP due to large mass. • Silicon vertex tracker (VTX) upgrade for PHENIX • Heavy flavor tagging • spatial resolution s ~ 77mm • Large acceptance  |h| < 1.2, Df～2p • Poster : Hidemitsu ASANO on 16 Aug 2011 • Poster : Ryohji AKIMOTO on 16 Aug 2012 • Physics observables with VTX • Nuclear modification factor for heavy flavor RAA • Talk : RachidNouicer on 17 Aug 2012at 3:00 PM • Azimuthal anisotropy for heavy flavor Au Au QM2012 Washington 13-18 Aug

4. 2. Method (1) Event Plane Method : Beam Beam Counter (to avoid auto-correlation effects) Res = BBC v2 <cos2(YBBC_N- YBBC_S)> v3 VTX 0 10 20 30 40 50 60 70 80 0 10 20 30 40 50 60 70 80 centrality (%) centrality (%) Track reconstruction • VTX (high position resolution) • + Central Arm (high momentum resolution) • Central Arm track was associated with stand-alone track of VTX BBC BBC VTX f VTX Electron Identification • Electron identification detector of central arm were used. -3.9 -3.1 -1.2 1.2 3.1 3.9 h QM2012 Washington 13-18 Aug

5. 2. Method (2) • DCA decomposition of charm and bottom • D and B mesons travel before semi-leptonic decay to electron. e Side View of VTX Lifetime (ct) D0 : 125 mm B0 : 464 mm DCA D Au Au B e • We know the shape of each component from Montecarlo simulation. • By simultaneous fitting of DCA distribution, each component can be separated statistically. QM2012 Washington 13-18 Aug

6. Charged Hadron v2 and v3 • v2 and v3 of h± has reduced background by application of DCA cut < 200um. • v2are consistent with previous measurements of p0 v2 in high pT region. • Extend to high pTregion for v3. • Good agreement with previous data in low pT region. • A non-zero v3 is still observed in high pT region. PHENIX PHENIX QM2012 Washington 13-18 Aug

7. Eta Dependence of v2 for Charged Hadron (VTX Stand-Alone Tracking) • Charged hadron v2 was measured with VTX. • Event plane : BBC • Track reconstruction : stand-alone track of VTX • Good agreement with the previous results from PRL 107, 252301. • Analysis using multi-particle correlation method with VTX stand-alone track is possible in the future analysis. • No hdependence observes within • |h| < 1.2 at low pTregion. Poster : Hiroshi NAKAGOMI on 16 Aug 2012 QM2012 Washington 13-18 Aug

8. 3. Electron v2 (Conversion Electron) Inclusive electron components Associated Hit Hit by track Random hit Large background is conversion electron  DCA • Conversion tagged electrons : • Require another hits around track associated hit. • Conversion electron events • can be selected by applying • conversion tag cut + |DCA| < 300 mm Conversion Tag BG |DCA| < 300 mm charm Dalitz + Conversion B-field bottom QM2012 Washington 13-18 Aug

9. 3. Electron v2 (Conversion BG Rejected Electrons) Conversion Veto Cut BG charm Dalitz + Conversion • Conversion veto electrons : • Require no hit around track associated hit. • Charm enhanced events • can be selected by applying • Conversion veto cut + |DCA| < 200mm • Each components are decomposed by using DCA distribution. bottom BG charm Dalitz + Conversion bottom QM2012 Washington 13-18 Aug |DCA| < 200 mm

10. Electron v2 Conversion tagged electron Charm enhanced : Ratio of each components. Those values can be derived from DCA decomposition. : charm enhanced v2 (VTX-PHENIX) : charged hadron v2 (VTX-PHENIX) : PR C 84, 044905 : used three kinds of value (-0.2, 0., 0.2). Fluctuation were included in sys. error QM2012 Washington 13-18 Aug

11. 5. Charm v2 Run11 VTX-PHENIX HF v2 PRL. 84, 044905 • Non-zero v2 of charm was observed. • Obtained charm v2 was consistent with previous HF v2. • Because of small fraction of bottom at low pT, HF v2 is thought as charm v2. QM2012 Washington 13-18 Aug

12. 6. Summary • Azimuthal anisotropy measurements had been done with VTX in AuAu 200 Gev. • Used generalized event plane method. • Extend to high pT region with low background. • Measured charged hadron v2 and v3. • Charged hadron v2 at high pT region were consistent with previous results of p0 v2. • Non-zero v3 was observed at high pTregion. • h dependence of charged hadron v2 was measured using stand-alone track of VTX. • h dependence was not observed within |h| < 1.2 at low pT region. • With the DCA decomposition, first measurements of charm v2 had been done. • Non-zero v2 of charm was observed. • Next Step: • Statistic error can be improved by using remaining data and fine tuning the analysis. • Bottom v2 will be obtained by using more statistics. • Poster : Takashi HACHIYA on 16 Aug 2012 QM2012 Washington 13-18 Aug

13. Back Up Slides QM2012 Washington 13-18 Aug

14. Invariant Yield Spectra HF electrons in Au+Au at 200 GeV • Use VTX to tag Dalitz and conversion electron • Determine HF components in inclusive electron

15. Decomposition of the DCA Distributions Charm and Bottom Measurements 90% heavy flavor e • - Our p0 measurements give us a good handle on the photonic background • In addition, most conversion electron backgrounds are tagged and vetoed. • Charm and Bottom events generated by PYTHIA run through full GEANT simulation determine the DCA shape of charm and bottom decays • Charm to bottom ratio is obtained from the fit to the DCA distribution of measured electrons Photonic BG is small after conversion VETO

16. 3. Charged Hadron v2 2011 VTX-PHENIX PRL. 105, 142301 (2010) • Comparison with v2 of p0 from PRL 105, 142301 • v2 of h± has reduced background by application of DCA cut < 200um. • Results are consistent with previous measurements of p0 v2 in high pT region. QM2012 Washington 13-18 Aug

17. Charged Hadron v3 2011 VTX-PHENIX PRL. 107, 252301 • Comparison with v3 of charged hadrons from PRL 107, 252301. • Good agreement with previous data in low pT region. • In high pT region, a non-zero v3 is still observed. QM2012 Washington 13-18 Aug

18. Run11 VTX-PHENIX g v2 PRL. 84, 044905 HF v2 PRL. 84, 044905 3. Electron v2 Inclusive electron without DCA cut Photonic v2 with DCA cut Charm enhanced v2 with DCA cut + |DCA|<300mm + |DCA|<200mm : Ratio of each components. Those values can be derived from DCA decomposition. : used three kinds of value (-0.2, 0., 0.2). Fluctuation were included in sys. error : charm enhanced v2 (VTX-PHENIX) : PR C 84, 044905 : charged hadron v2 (VTX-PHENIX) QM2012 Washington 13-18 Aug

19. 3. Charged Hadron v3 Run11 VTX-PHENIX Phys. Rev. Lett. 105, 142301 (2010) QM2012 Washington 13-18 Aug

20. QM2012 Washington 13-18 Aug

21. Conversion Tagging (Isolation Cut) Primary Electron (hadron) distance distance Conversion B-field Distance by hadrons Distance by electrons Associated Hit Associated Hit Hit by track Random hit Reco track [cm]  e DCA • Hadrons • Symmetric shape  random associate • Eletrons • Asymmetric shape  pair • Same shape for all layers. • Determine isolation cut by using all layers. QM2012 Washington 13-18 Aug

22. Charged Hadron v2 Run11 VTX-PHENIX Phys. Rev. Lett. 105, 062301 (2010) ppg098 Centrality dependence of v2 as a function of pT. 5% centrality step CNT track was associated with VTX. Required isolation cut and |DCA| < 700 mm to reduce miss-association tracks except for 0-5% centrality bin. Our data is consist with the results from PPG098. QM2012 Washington 13-18 Aug

23. VTX Barrel BEAM VIEW SIDE VIEW beam QM2012 Washington 13-18 Aug