1 / 20

Observables in heavy-ion collisions at CMS

Observables in heavy-ion collisions at CMS. Haidong Liu 2009-10-21. outline. The CMS detector Review of the ‘golden’ observables Other interesting observables for me LHC schedule (latest version). CMS detectors. Silicon pixel detector Silicon microstrip tracker

axelle
Download Presentation

Observables in heavy-ion collisions at CMS

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Observables in heavy-ion collisions at CMS Haidong Liu 2009-10-21

  2. outline • The CMS detector • Review of the ‘golden’ observables • Other interesting observables for me • LHC schedule (latest version)

  3. CMS detectors • Silicon pixel detector • Silicon microstrip tracker • Electromagnetic Calorimeter • Hadronic Calorimeter • Superconducting Solenoid • Muon detectors • Drift Tubes (barrel) • Cathode Strip Chambers (endcaps) • Resistive Plate Chambers (barrel+endcaps) • CASTOR Calorimeter (forward) • Zero Degree Calorimeter (forward) (Jet with cone size R=0.5)

  4. Low pT PID spectra for Pb+Pb @ 5.5 TeV

  5. Event plane resolution b=9fm of Pb+Pb collisions -- the expected resolution is 0.37 rad with ECAL NA49 Phys. Rev. C 68 034903 PHOBOS nucl-ex/0610037 PHOBOS Nucl. Phys. A 774 523–26 STAR AIP Conf. Proc. 870 691–4 Voloshin S A and Poskanzer A M Phys. Lett. B 474 27–32 Kolb P F, Sollfrank J and Heinz U W ,Phys. Rev. C 62 054909 Teaney D, Lauret J and Shuryak E V nucl-th/0110037 Φsimu-Φreco J. Phys. G: Nucl. Part. Phys. 34 (2007) 2307-2455

  6. high pTcharged particle spectra Expected reach (0.5 nb-1): pT~ 300 GeV/c (inclusive hadrons)

  7. Jet Jet ET distributions for 1 month data Jet ET reco resolution

  8. Expected quarkonia signalsin one month data (di-muon) J. Phys. G: Nucl. Part. Phys. 34 (2007) 2307-2455 Assuming no quarkonia suppression Acceptance Solid line: Both μ |η|<2.4 dashed line: Both μ |η|<0.8

  9. (arbitrary) Stat. errors of Y’/Y ratios Curves are calculations for different initial conditions and different assumption of Tdiss

  10. Z0μμ signal 1 month data: ~11000 (Z μμ) J. Phys. G: Nucl. Part. Phys. 34 (2007) 2307-2455

  11. Tagged Jet An ideal way to measure parton energy loss in the medium

  12. Other interesting observables • Open charm & bottom • DK+π • DK+μ+νμ (K μ correlations) • B+J/psi K+ (BR~0.001) • B0J/psi K0 (BR~0.001) • X-section and flow are both very interesting • Z boson reconstruction • Ze+e- (BR 3.4%) • ZJets

  13. For B and D reconstruction • Low pt track efficiency is not bad • Ks can be reconstructed nicely • dEdx can help on PID pion efficiencies in pp and PbPb collisions Ks in pp Pixel+tracker

  14. DK+e+νe(K e correlations at STAR) PYthia simulation at 200 GeV 3<pT(e)<6 GeV/c 3<pT(e)<6 GeV/c Φ<36 degree

  15. DK+e+νe(K e correlations at STAR) Run5 & Run6 pp data

  16. Z boson reconstruction • Ze+e- (BR 3.4%) • Large energy electrons (>50 GeV) identification should be easy • ZJets • Huge background • Depends on the study of the jet reco algorithm

  17. LHC schedule • Preparing for mid-November start of beam operations • A few weeks for first collisions from then • First 7 TeV collisions in week before Christmas break • Initial operations at 7 TeV (3.5+3.5) • “Energy scan” (0.9, 7, 8-10TeV) • Pb+Pb run still scheduled at the end of p+p run • Now foreseen to start Nov 1 2010

  18. Thank you

  19. pp@14TeV L~1034cm-2s-1 PbPb@5.5TeV L~1027cm-2s-1 CMS detectors • Silicon pixel detector • Silicon microstrip tracker • Electromagnetic Calorimeter • Hadronic Calorimeter • Superconducting Solenoid • Muon detectors • Drift Tubes (barrel) • Cathode Strip Chambers (endcaps) • Resistive Plate Chambers (barrel+endcaps) • CASTOR Calorimeter • Zero Degree Calorimeter (Jet with cone R=0.5)

  20. Photon tagged jets CMS NOTE HIN-07-002 Quenched FF Unquenched FF models used in this analysis PYQUEN: selected QCD channels w/ jet quenching PYTHIA: selected QCD channels w/o jet quenching HYDJET: underlying corresponding Pb+Pb events Isolated photon + away side jet Ratio of quenched and unquenched FF Detailed quantitative studies of medium-induced parton energy-loss possible.

More Related