1 / 84

Review of Scalar Meson Production at = 7TeV in CMS, U(1)' Gauge Extensions of the MSSM and

Review of Scalar Meson Production at = 7TeV in CMS, U(1)' Gauge Extensions of the MSSM and Calorimetry for Future Colliders. Thesis Defense. Burak Bilki. June 16, 2011. The Compact Muon Solenoid (CMS) Detector at the Large Hadron Collider (LHC). CMS Subdetectors.

shiloh
Télécharger la présentation

Review of Scalar Meson Production at = 7TeV in CMS, U(1)' Gauge Extensions of the MSSM and

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. Review of Scalar Meson Production at = 7TeV in CMS, U(1)' Gauge Extensions of the MSSM and Calorimetry for Future Colliders Thesis Defense Burak Bilki June 16, 2011

  2. The Compact Muon Solenoid (CMS) Detector at the Large Hadron Collider (LHC)

  3. CMS Subdetectors

  4. CMS Subdetectors – Transverse Slice http://cms.web.cern.ch/cms/Detector/FullDetector/index.html

  5. CMS Data Taking First collisions at =900 GeV started in 2009. First =7 TeV collision was in March 2010. In 2010, integrated luminosity reached ~50 pb-1. Two distinct run periods based on beam settings: Run2010A and Run2010B. By the end of 2011, an integrated luminosity of 3-4 fb-1 is within reach. The reasonable target by the end of 2012 is 10 fb-1.

  6. Scalar Meson Production at = 7TeV in CMS

  7. Reason of Interest Whether the scalar mesons really exist or not is an important problem in hadron physics. It is still a difficult yet interesting topic. They have the same quantum numbers as the vacuum (JPC=0++) hence they can condense into the vacuum and break a symmetry such as a global chiral symmetry. There are several theoretical models for their structures (diquark-antidiquark bound states, glueballs, molecules, etc.). I=1/2 states: (or ), . I=1 states: , . I=0 states: (or ), , , , .

  8. Search for Scalar Meson Production in Process • Datasets: • /MuOnia/Run2010A− Dec22ReReco_v1/RECO • /MuOnia/Run2010B− Dec22ReReco_v1/RECO • MC Simulation (for acceptance): • /Psi2SToJpsiPiPi_2MuPEtaFilter_7TeV-pythia6/Fall10 - START38_V12-v1/GEN-SIM-RECO • Search Path: • Reconstruct . • Reconstruct . • Look at mass spectrum.

  9. Search for Scalar Meson Production in Process • Level 1 (hardware) muon trigger selection “L1_DoubleMuOpen OR L1_DoubleMu3”. • Search for two oppositely charged muons with pt > 2 GeV/c (transverse momentum). • Require at least 10 hits in the silicon strip tracker and 12 hits in the entire tracker system. • Fit a vertex to the muon pair and retain if the fit is valid with a probability of at least 0.1% and the invariant mass of the muon pair is within 50 MeV/c2 of the PDG (Particle Data Group) value (3.096916 GeV/c2).

  10. Search for Scalar Meson Production in Process • Tracks • No particle ID for tracks (assign pion mass to all tracks). • Track pt > 0.4 GeV/c (transverse momentum). • Require at least 1 hit in the pixel detector and at least 10 hits in the tracker.

  11. Search for Scalar Meson Production in Process • Fit a vertex to all pions and muons with mass constraint on muons. • Retain if vertex probability is more than 2% and , • and the four tracks remain in < 1

  12. Unbinned maximum likelihood fit Green: Selection Red: Background

  13. Search for Scalar Meson Production in Process 13 T. Komada et.al., Phys. Lett. B 508, 31 (2001)

  14. Search for Scalar Meson Production in Process • Fit the mass spectrum ( ) with a coherent sum of and production amplitudes. • : production coupling • : production phase • : coupling

  15. Search for Scalar Meson Production in Process

  16. Search for Scalar Meson Production in Process Describe the gluon emission by a multipole expansion of S (and possibly D) wave. Formalism by T. Yan, Phys. Rev. D 22, 7, 1652 (1980) Implemented by CDF and BES collaborations.

  17. Search for Scalar Meson Production in Process Free (shape) parameter Higher Order terms

  18. Search for Scalar Meson Production in Process Multipole expansion Higher order multipole expansion

  19. Systematic Effects Binning: 5 MeV/c2 , 10 MeV/c2 Trigger: High Level Trigger Selection Background Bias: Differences from the fit values are added in quadratures for

  20. Systematic Effects: Binning

  21. Systematic Effects: Trigger Selection

  22. Systematic Effects: Background

  23. Search for Scalar Meson Production in Process: Summary BES BES CDF

  24. References T. Komada et. al., Phys. Lett. B 508, 31-36 (2001). M. Ishida et. al., Phys. Lett. B 518, 47-54 (2001). M. Ablikim et.al., Phys. Lett. B 598, 149-158 (2004). L. Hongbo (on behalf of BES Collaboration), Eur. Phys. J. A 31, 461-464 (2007). J. Z. Bai et al., Phys. Rev. D 62, 032002 (2000). M. Ablikim et.al., Phys.Lett.B 645, 19 (2007). D. Alde et.al., Phys. Lett. B 397, 350-356 (1997). E. M. Aitala et.al., Phys. Rev. Lett., 86, 5, 770 (2001). E. M. Aitala et.al., Phys. Rev. Lett., 86, 5, 765 (2001). H. Muramatsu et. al., Phys. Rev. Lett., 89, 25, 251801 (2002). A. Abulencia et. al., Phys. Rev. Lett. 96, 102002 (2006). T. Yan, Phys. Rev. D 22,1652 (1980). G. ’t Hooft et.al., Phys. Lett. B 662, 424-430 (2008). T. N. Pham, Phys. Lett. B 217, 165-168 (1989). L. Montanet, Nucl. Phys. (Proc. Suppl.) B 86, 381-388 (2000). N. N. Achasov, Phys. Part. Nucl. 36, 146-149 (2005) . N. N. Achasov et. al., Nucl. Phys. (Proc. Suppl.) B 162, 127-134 (2006). S. Ishida et. al., Phys. Lett. B 539, 249 (2002). G. Mennessier et. al., Phys. Lett. B 665, 205 (2008). T. Kojo et. al., Phys. Rev. D 78, 114005 (2008). CMS Collaboration, PAS MUO-10-002 (2010). K. Nakamura et. al. (Particle Data Group), J. Phys. G: Nucl. Part. Phys. 37 075021 (2010).

  25. U(1)' Gauge Extensions of the MSSM

  26. U(1)' Model

  27. U(1)' Model

  28. U(1)' Model

  29. U(1)' Model

  30. U(1)' Model

  31. U(1)' Model

  32. U(1)' Model

  33. U(1)' Model

  34. U(1)' Model Search in CMS Events of each signal type was produced by CalcHEP and hadronized by PYTHIA 6 with CTEQ6L parton distributions. Signal 4A is not analyzed a it will be heavily suppressed compared to the others.

  35. U(1)' Model Search in CMS Event Selection: (Missing transverse energy) (pseudorapidity) and gaugino masses soft-breaking mass that mixes and gauginos.

  36. U(1)' Model Search in CMS Analysis to compare MSSM andU(1)', no background study. Two medium mixing cases are investigated in U(1)' model: at scenario is considered.

  37. U(1)' Model Search in CMS - Signal 1

  38. U(1)' Model Search in CMS - Signal 1 38

  39. U(1)' Model Search in CMS - Signal 1 39

  40. U(1)' Model Search in CMS - Signal 2 40

  41. U(1)' Model Search in CMS - Signal 3A 41

  42. U(1)' Model Search in CMS - Signal 3A 42

  43. U(1)' Model Search in CMS - Signal 3B 43

  44. U(1)' Model Search in CMS - Signal 3B 44

  45. U(1)' Model Search in CMS - Signal 4B 45 45 45 45

  46. U(1)' Model Search in CMS - Signal 4B 46 46

  47. References S. Cecotti et.al., Phys. Lett. B 156, 318 (1985). G. Cleaver et.al., Phys. Rev. D 57, 2701 (1998). D. M. Ghilencea et.al., JHEP 0208, 16 (2002). D. A. Demir et.al., Phys. Rev. D 59, 15002 (1999). D. A. Demir et.al., Phys. Rev. Lett. 100, 91804 (2008). A. Ali et.al., Phys. Rev. D 79, 95001 (2009). V. Barger et.al., Phys. Lett. B 644, 361 (2007). 47

  48. Calorimetry for Future Colliders

  49. Upgrade for CMS Hadron Forward (HF) Calorimeters

  50. CMS Hadron Forward (HF) Calorimeters Interaction point (~11m this way) • The Hadron Forward (HF) Calorimeter is a part of HCAL. • One on each end of CMS, covering 3<η<5 (0.77°-5.7°). • Composed of quartz fibers embedded in a 1.65 meter steel absorber. • Two lengths of fiber • Readout boxes containing PMTs sit behind it at 3< η<3.2.

More Related