Presentation is loading. Please wait.

Presentation is loading. Please wait.

Heavy Flavor and Charged Hadron Flow measurement using Silicon Vertex Detector at PHENIX Hiroshi Nakagomi for the SVX Group and the PHENIX Collaboration.

Similar presentations


Presentation on theme: "Heavy Flavor and Charged Hadron Flow measurement using Silicon Vertex Detector at PHENIX Hiroshi Nakagomi for the SVX Group and the PHENIX Collaboration."— Presentation transcript:

1 Heavy Flavor and Charged Hadron Flow measurement using Silicon Vertex Detector at PHENIX Hiroshi Nakagomi for the SVX Group and the PHENIX Collaboration Univ. of Tsukuba/RIKEN 2013/06/23 1

2 Heavy Flavor(c,b) in Heavy Ion Collisions  Mainly created at initial hard scattering  Traverse and interact with the hot and dense medium. Good probe to study hot and dense medium  Previous PHENIX HF result - R AA is suppressed ( c,b -> e) - Non zero v 2 ( c,b -> e ) Surprising result But the result is mixture of c and b -Separating c and b is needed PRL

3 η dependence of v 1, v 2,v 3  v 1 as function of η:STAR 0-40% AuAu 200GeV Phys.Rev.Lett η 3 η Phys.Rev. C AuAu200GeV 10-40% NN2012:STAR AuAu200GeV 3  v 2,v 3 as function of η:STAR - v 2 :Blue data point - v 3 :Red data point - |η|<1v 2, v 3 Flat distribution

4 Silicon Vertex Detector (VTX) 4  Silicon Vertex detector was installed from run Physics Motivation ・ Measurement of heavy flavor -Detector design ・ Barrel Type & 4 layers Inner 2 layers : pixel detector Outer 2 layers : strip detector ・ Δφ~2π ・ |η|<1.2 VTX:|η|<1.2 MPC:3.1<|η|<3.7 BBC:3.0<|η|<3.9 CNT:|η|<0.35 SMD/ZDC η dN/dη

5 VTX Track Reconstruction 5 VTX DC+PC RICH TOF EMCAL Central Arm DcTrack B3 B2 B1 B0 VTX  VTX Standalone Tracking - VTX can reconstruct charged particle tracks (require more than 3 hits on VTX) - Low momentum resolution - |η|<2.0 - Measurement Primary Vertex  Central Arms + VTX tracking - Central Arms track is associated with the VTX clusters(charged particle hits) - High momentum resolution - |η|< Measurement DCA There are two types of tracking

6 Separating c and b using DCA Lifetime (c  ) D 0 : 125  m B 0 : 464  m DCA Au D B e e Side View of VTX We know the shape of each component from PYHIA simulation. By simultaneous fitting of DCA distribution, each component can be separated statistically. D and B mesons travel before semi-leptonic decay to electron  Measure DCA to separate c and b components of heavy flavor spectra. DCA corresponds to the life time. 6

7 b->e/(c->e+b->e) in pp collision  Separate b->e, c->e  Consistent with previous PHENIX result and FONLL calculation 7

8 v 2 、 v 3 and Event Plane resolution 8  p T /η dependence of v 2, v 3 - CNT- SVX track |η|< standalone track |η|<1.5  η dependence of event plane resolution - Spectator vs Participant EP correlation - Participant vs Participant EP correlation

9 Analysis Method : Event Plane Method 9 Event Plane(The angle a lot of the particles are emitted in) The angle the particles are emitted in x y Event Plane with elliptic moment

10 10 BBC South/North/South + North centrality[%]/ CNT+VTX tracks (CNT tracks was associated with stand-alone track of VTX) or VTX standalone tracks Track reconstruction Event Plane measurement η BBC North BBC South φ 2π 0 VTX CNT Analysis Method : Event Plane Method

11 v 2 and v 3 of charged hadron has reduced background by application of DCA cut < 200um. v 2 are consistent with previous measurements of  0 v 2 in high p T region. 11 PHENIX v 2,v 3 : p T dependence (CNT+VTX tracks) PHENIX Extend to high p T region for v 3. Good agreement with previous data in low p T region. A non-zero v 3 is still observed in high p T region.

12 v 2 :p T dependence(VTX standalone tracks) 12  Comparison with previous PHENIX result (PRL ) v 2 using CNT tracks and v 2 using VTX standalone tracks - Standalone tracks p T region is 0.25

13 v 2 : η dependence(standalone tracks)  Comparison to PHOBOS v 2 - PHOBOS : centrality 25-60%, p t > 0[GeV/c] - PHENIX : centrality 20-60%, 0.25


14 Event Plane Resolution: η dependence SVX 0.5η slice EP resolution : 12 EP |η|<3  EP resolution reflects amplitudes of v n in sub-events and their Multiplicity layer0 layer1 layer2 layer η BBC SMD BBC SVX EP Resolution Raw EP Correlation SMD/BBC EP Resolution 14

15 EP Resolution : Similar to v 1 distribution Depend on SMD Plane: SMD S> SMD SN > SMD N 15

16 Strong centrality dependence At η=0, Multiplicity is high. Triangular shape No EP selection dependence EP Resolution : 16

17 At Mid-rapidity, data points are minus value, - Momentum Conservation The data points become plus value at the rapidity EP is measured, - Non flow effect EP Resolution : η>0 η<0 17

18 Similar to Psi2 Correlation using SMD The data points become lager at the rapidity EP is measured - Non flow Effect EP Resolution : 18

19 Similar to Psi2 Correlation – Symmetry distribution Weak Centrality dependence like v3 EP Resolution : 19

20 Summary 20  Heavy Flavor Separate c and b in pp collision  Event Plane resolution (SVX 0.5 slice) Psi1 vs Psi1 - Spectator vs Participant : similar to v1 、 Depend on SMD( SMD S > SMD SN > SMD N) - Participant vs Participant : momentum conservation, non flow Psi1 vs Psi2 - Spectator vs Participant : similar to v2 Psi2 vs Psi2 - Similar to Psi2 resolution using SMD, non flow Psi3 vs Psi3 - Similar to Psi2 resolution distribution  Charged Hadron v 2, v 3 p T dependence|η|<0.35 : Consistent with previous result p T dependence |η|<1.5 : Consistent with previous result below 1 [GeV/c] η dependence : Consistent with PHOBOS result

21 v 2 : 21 VTX 0.5-η slice VTX cluster(charged particle hit) Z 0 layer0 layer1 layer2 layer3 Used clusters were in these region was measured in this region(Δη=0.5) BBC South BBC North Δη=0.5 centrality[%] Au+Au √S NN = 200GeV

22 22 VTX 0.5-η slice VTX cluster(charged particle hit) centrality[%] I divided VTX into 12 parts by 0.5η slice layer0 layer1 layer2 layer3 η η coordinate Au+Au √S NN = 200GeV v 2 :

23 layer0 layer1 layer2 layer η I calculated correlation between BBC NS and these region. 23 VTX 0.5-η slice VTX cluster(charged particle hit) centrality[%] Au+Au √S NN = 200GeV v 2 :

24 24 VTX 0.5-η slice VTX cluster(charged particle hit) centrality[%] centrality[%] η Au+Au √S NN = 200GeV v 2 :

25 v2:v2: 25  η dependence of v 2 using cluster(charged particle hit) - no BG subtraction and no p t selection  v 2 around EP measurement region is higher than v 2 in other region - Non flow effect is seen - Non flow effect seems to be asymmetry. We should separate Mid-rapidity side : Δη=1.5, Forward rapidity side : Δη=1 η EP measurement region(0.5<η<1) Au+Au √S NN = 200GeV performance plot

26 η v2:v2: 26 0<|η|<0.50.5<|η|<1 1<|η|< <|η|<2 Au+Au √S NN = 200GeV  v 2 using EP measured in other rapidity region( Black:η 0) In other EP measurement regions, v 2 distributions also look asymmetry. performance plot

27 EP Resolution : BBC Psi2, Psi3 27

28 EP Resolution : SMD Psi1, Psi2 28

29 29 dN/dη

30

31

32


Download ppt "Heavy Flavor and Charged Hadron Flow measurement using Silicon Vertex Detector at PHENIX Hiroshi Nakagomi for the SVX Group and the PHENIX Collaboration."

Similar presentations


Ads by Google