1 / 17

Tridas Scenario and Physics Channels

Luminosity: 2x10 33 cm -2 s -1 Tridas scenario: 50 kHz Level-1 trigger rate (16 kHz with safety factor) 8 physics channels studied (A-H) A: Smuons at Snowmass point 1a - m L m L with m L -> m   B: Charginos/neutralinos at Snowmass point 1a -      

gyan
Télécharger la présentation

Tridas Scenario and Physics Channels

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. Luminosity: 2x1033 cm-2s-1 • Tridas scenario: 50 kHz Level-1 trigger rate (16 kHz with safety factor) • 8 physics channels studied (A-H) • A: Smuons at Snowmass point 1a - mLmL with mL -> m • B: Charginos/neutralinos at Snowmass point 1a -  • with  ->  and  -> ;  -> ;  -> e • C: Gluinos/squarks Snowmass point 1a • D: Gluinos/squarks Snowmass point 2 • E: Sparticles JetMet mSUGRA4 • F: Sparticles JetMet mSUGRA5 • G: Sparticles JetMet mSUGRA6 • H: WW with W -> mn (benchmark channel) ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ Tridas Scenario and Physics Channels

  2. Snowmass point 1a Snowmass point 2 Parameter Choice tan  = 10, sgn(m) = + A0 = - 100 GeV (A,B,C) A0 =  GeV (E,F,G)

  3. mSUGRA Jet and Missing ET distributions

  4. Monte Carlo Input A, B, C, D, H: PYTHIA 6.158 E, F, G: ISAJET 7.51 Parton distribution functions CTEQ5L used for all channels. 1000 events for SUSY channels, 2000 events for WW channel. On average 3.5 minimum bias events produced with PYTHIA 6.158 added.

  5. Detector and Trigger Simulation CMSIM 125 used for hit simulation, separately for signal and pile-up. Digis produced with ORCA 6, mixing signal plus in-time pile-up. Out-of-time pile-up simulated by superposing bunch crossings -5, …, +3. HCAL non-linearity correction applied. Intrinsic RPC noise not added due to CPU time constraints. Level-1 performance simulated in ORCA. Bit-wise arithmetic used wherever possible. Results are given at the end of the Level-1 chain, i.e. at the output of the Global Trigger.

  6. Trigger Menu Thresholds chosen to yield total rate of 16 kHz, which are allocated to physics triggers at Level-1. Muon thresholds are from the DAQ/HLT TDR. Bandwidth quota is divided into four roughly equal groups: /  e /ee / Jets, ET sums and combinations Total rate is smaller than sum of rates for 4 groups due to overlaps. } 3.6 kHz } 4.3 kHz } 3.0 kHz } 3.6 kHz

  7. Nr. of events passing L1 trigger in its fiducial volume Efficiency = Nr. of events generated (no geometrical restrictions) Efficiencies Individual efficiency: eff. of a trigger as if it were the only trigger applied In practice: triggers overlap Additional efficiency: events found by previous trigger not counted (order of trigger conditions relevant) Exclusive efficiency: eff. for events found by one and only one trigger

  8. Efficiencies A-D, H (WW)

  9. Efficiencies E, F, G (mSUGRA) Efficiencies at the upper mass reach of Tevatron Run II

  10. Total Efficiencies Channel Total efficiency A 93.4 % B 72.3 % C 97.9 % D 100.0 % E 96.2 % F 96.3 % G 88.9 % H 81.3 % Chargino/neutralino channel has lowest efficiency.

  11. ~ ~   : generated ET vs h of highest-ET electron ET is either low or electrons are outside trigger acceptance

  12. ~ ~   : generated ET and E of invisible particles Can trigger on missing ET help? Invisible ET about the same for accepted and rejected events, whilst E is higher for rejected than accepted events! Rejected events tend to balance their contributions in ET . Probability for cancellation high due to many invisible particles.

  13. Effects of thresholds, resolution, acceptance For a qualitative appreciation of the different effects the m and mm trigger efficiencies were studied for smuons (A) (em = 92.5%, em = 68.8%) and gluinos/squarks (C) (em = 27.8%, em = 13.8%). Smuons Squarks/gluinos Generated pT of 2 highest-pT muons

  14. pT of Level-1 Muon Candidates Smuons Squarks/gluinos Single-muon threshold Level-1 pT of 2 top muons

  15. h of Generated and Level-1 Muons Generated h of 2 highest-pT muons Smuons Squarks/gluinos Level-1 h of 2 top muons m trigger acceptance boundary

  16. Conclusions • Level-1 trigger efficiencies for 7 SUSY channels and WW studied for the • initial low luminosity LHC run with scenario of 50 kHz maximum Level-1 • trigger rate • Most efficiencies are good, over 90% • Lower efficiency for charginos/neutralinos comes mainly from physics

More Related