Presentation is loading. Please wait.

Presentation is loading. Please wait.

Relativistic Heavy Ions Experiment III Strangeness and Heavy Flavour.

Similar presentations


Presentation on theme: "Relativistic Heavy Ions Experiment III Strangeness and Heavy Flavour."— Presentation transcript:

1 Relativistic Heavy Ions Experiment III Strangeness and Heavy Flavour

2 V 0 -Topology K 0     Kink-Topology K ±      Discovery of Strange Particles

3 --  K0K0 -- p ++ -- Associated Production of Strange Particles

4 K - + p   0  + K 0    0 (  S = -1, weak interaction)  p+  - (  S = -1, weak interaction) Multiple Strange Particles:  (Cascades)

5 Main Strangeness Carriers in A+A Collisions: K and  ss = Strangeness Conservation  K 0 (ds)K + (us)  Isospin Symmetry  K - (us)K 0 (ds)  Isospin Symmetry   (uds)  >>  If baryon density is high

6 Multiple Strange Particles from String Fragmentation M. Bleicher et al., Phys. Rev. Lett. 88 (2002), 202501

7 Strange Particle Production by qq- and Gluon-Fusion

8 Particle Identification in NA49 dE/dx measured in TPCs  Large acceptance  Resolution 3-4% Time-of-flight  Mid-rapidity  Resolution 60 ps Example: Pb+Pb @ 40 AGeV p dE/dx

9 Time Projection Chamber: NA49 Main-TPC Field cage Vertex-TPC

10 TPC (NA49): Working Principle

11 High Voltage-Electrode (100 kV) Fieldcage Readout Chamber Time Projection Chamber: ALICE Volume: 88 m 3 Drifttime 88  s Number of readout channels: 570132 E-Field 510 cm

12 ALICE-TPC

13 TPC (ALICE): Working Principle of Readout Chambers Gas amplification at the anode wires Induced signal on pads:  x/y-coordinates Drifttime  z-coordinates Signalheight  Energy loss of particles  Particle identification beam axis

14 Strangeness via V 0 Topology

15 Invariant Mass Spectra of K 0 s,  -,  - in Pb+Pb m inv (  +,  - ) (GeV/c 2 ) Entries K0sK0s --

16 NA57 @ SPS

17 NA57 Setup

18 Strange Particle Reconstruction in NA57 Si Pixels telescope target  1 M channels B 30 cm 5 cm    1.4 T 60 cm

19 Strangeness Enhancement by NA57

20

21 Energy Dependence of Particle Ratios  K +  /  +   K -  /  -   /   /   -  /   - +  +  /  UrQMD + HSD E.L. Bratkovskaya et al., PRC 69 (2004), 054907 Statistical hadron gas: P. Braun-Munzinger, J. Cleymans, H. Oeschler, and K. Redlich Nucl. Phys. A697 (2002) 902  s = 1

22 Heavy Flavour

23 M. Mangano, hep-ph/0411020 Beauty Production at the Tevatron (Run1+2, 2003)

24 Jet Quenching

25 Energy Loss of Heavy Quarks light (M.Djordjevic PRL 94 (2004))

26 acceptance: p t > 0.2 GeV/c r  1.5 GeV/c D 0  K + +  - c  ~ 124  m Reconstruction of D-Mesons

27 D-Mesons w/o Vertex-Reconstruction

28 Energy Dependence of cc-Cross section

29 Primary Vertex B e X d0d0 rec. track B   e  + X c  ~ 500  m semi-leptonic Reconstruction of B-Mesons

30 B  J/  + X Reconstruction of B-Mesons

31 Transition Radiation Produced by charged particles passing the border between two media of different di-electricity constant Predicted by V.L. Ginzburg and I.M. Frank 1946 Properties:  Energyspectrum in keV-region  Emissionangle ~1/  (Lorentz-Factor) Spectrum and yield determined by:  Number and distance of borders  Thickness and plasma frequency of materials  Velocity of charged particle (  ) Possible radiators:  Regular foil stack  Fiber materials  Foam-like materials measured spectrum for electrons with 2 GeV/c momentum

32 Zählgas: Xe/CO 2 Driftlänge: 3cm Transition Radiation Detector Electron-/pion-discrimination: e - (p = 5 GeV/c):   10000  - (p = 5 GeV/c):   36 Radiator made of microfibers Polypropylene, 17  m

33 TRD Setup in ALICE TRD in numbers:  540 chambers  6 planes  18 sectors (supermodule)  Total area: 736 m 2 (3 tennis courts)  Gasvolume: 27,2 m 3  Resolution (r  ) 400  m  Number of read out channels: 1.2  10 6 TRD Supermodule TPC

34 Expected Di-Electron Spectrum


Download ppt "Relativistic Heavy Ions Experiment III Strangeness and Heavy Flavour."

Similar presentations


Ads by Google