recent atlas results woochun park @ usc physics seminar april 13, 2011 the atlas detector heavy...
TRANSCRIPT
W. Park USC Physics Seminar 1
Recent ATLAS results
Woochun Park@ USC Physics Seminar
April 13, 2011
• The ATLAS detector• Heavy Flavor Physics at ATLAS
• Observation of Charmonium, Upsilon & Charm Mesons• Inclusive differential cross-section of J/y production and Charm
Mesons.• Measurement of the fraction of non-prompt J/y decays & non-
prompt cross sections• Exclusive B-meson decays.
• Higgs Search at ATLAS (not today) • Summary and Outlook
April 13, 2011
W. Park USC Physics Seminar 2April 13, 2011
W. Park USC Physics Seminar 3
The ATLAS Muon Spectrometer
• Great stand-alone performance thanks to air core toroidal magnet field (0.3 – 1.2T)
• Designed for high pt muon sensitive to new physics.
• Fast Trigger Chambers– RPC (Resistive Plate Chambers)– TGC (Thin Gap Chambers)
• High-precision tracking chambers– MDT (Monitored Drift Tube Chambers)– CSC (Cathode Strip Chambers) 2.0 < |
h| < 2.7
• Crucial measurement by CSC before toroidal field and materials. • High counting rate area near the
beam axis ( > 200Hz/cm2)• Excellent track resolution ~60mm.• Good two track resolution• Good time resolution ~7ns
• 3 planes of trigger and precision chambers individuallyo Barrel: sagitta measuremento Endcap: point-angle measurement
MDT
TGC
CSC
RPC
April 13, 2011
W. Park USC Physics Seminar 4April 13, 2011
W. Park USC Physics Seminar 5April 13, 2011
W. Park USC Physics Seminar 6April 13, 2011
W. Park USC Physics Seminar 7
Observation of ccJ (1P) • Measurement of the cc cross-section in 7TeV pp collision is interesting
topic being actively worked by many theorists. Theoretical prediction of the cc production cross-sections is difficult due to P-wave divergences in the theory.
• One of the significant uncertainty of J/y cross-section measurement is cc
contribution through g J/ . y Measurement of cc cross-section will benefic J/y cross-section measurement.
• Two approaches:– Calorimetric Photon Information – Tracking Photon Information (ee pair conversion)
April 13, 2011
Mass (MeV) Mass-M(J/ )y BF(%) of g J/y
cc0 3414.75 317.83 1.16 ± 0.08
cc1 3510.66 413.74 34.4 ± 1.5
cc2 3556.20 459.28 19.5 ± 0.8
Very Preliminary
W. Park USC Physics Seminar 8April 13, 2011
W. Park USC Physics Seminar 9April 13, 2011
W. Park USC Physics Seminar 10April 13, 2011
W. Park USC Physics Seminar 11April 13, 2011
W. Park USC Physics Seminar 12
D*+ Cross-section Measurement using D0K3p
April 13, 2011
Validated result with independent decay channel.
W. Park USC Physics Seminar 13April 13, 2011
W. Park USC Physics Seminar 14April 13, 2011
W. Park USC Physics Seminar 15April 13, 2011
W. Park USC Physics Seminar 16
Evaluate Tracking Performance
D*+D0p; D0K3p D*+D0p; D0Kp
Preliminary
April 13, 2011
W. Park USC Physics Seminar 17April 13, 2011
W. Park USC Physics Seminar 18April 13, 2011
W. Park USC Physics Seminar 19April 13, 2011
W. Park USC Physics Seminar 20April 13, 2011
W. Park USC Physics Seminar 21April 13, 2011
12 3
W. Park USC Physics Seminar 22April 13, 2011
W. Park USC Physics Seminar 23April 13, 2011
W. Park USC Physics Seminar 24April 13, 2011
W. Park USC Physics Seminar 25April 13, 2011
W. Park USC Physics Seminar 26April 13, 2011
W. Park USC Physics Seminar 27April 13, 2011
W. Park USC Physics Seminar 28April 13, 2011
W. Park USC Physics Seminar 29April 13, 2011