1 / 23

Calibration of Trigger Thresholds in Calorimeter and Drift Chamber Using Kaon Decay Events

This study focuses on the tuning of trigger simulation parameters and calibration of calorimeter and drift chamber thresholds using prompt photons from KS→π0π0 events during the 2001 and 2002 data-taking periods. An effective threshold is derived by comparing photon cluster energies with trigger sector responses under specific unbiasing conditions. The calibration employed various data samples, particularly from neutral kaons, and examined the impact of hardware changes on trigger responses through a comprehensive analysis of data and simulation comparisons to optimize detection efficiency.

otto
Télécharger la présentation

Calibration of Trigger Thresholds in Calorimeter and Drift Chamber Using Kaon Decay Events

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. Tuning of trigger simulation parameters • (Bossi, Moulson, Palutan, Sciascia) • Calorimeter trigger thresholds calibration using • prompt photons from KSp0p0 events (2001 • and 2002 data). • Driftchamber trigger threshold calibration using • KSp+p- and K+K- events (2001 and 2002 data).

  2. Calorimeter trigger • An effective threshold is evaluated comparing the energy of a photon cluster (from KSp0p0 events) with the trigger sector response. An unbiasing condition is imposed to the remaining clusters of the event (two sectors fired). • During 2001 and 2002 data taking periods, a dishmap with unbalanced endcap thresholds has been used. A single step has been applied to the hardware thresholds of some endcap sectors at the beginning of 2002 data taking, to recover 2001 running condition. • Data samples used for calibration (neutral kaons DST’s): • 2001 run 20800-21800 = 37 pb-1 • 2002-ini run 23600-23980 = 26 pb-1 • new hardware map starting from run 24036 • 2002-mid run 24700-25000 = 17 pb-1 • 2002-end run 26090-26500 = 45 pb-1

  3. Barrel thresholds in the standard trigger simulation 2002-ini MC Th (MeV) data Z (cm)

  4. 2002-mid + 2002-end MC data

  5. Data/MC comparison after calibration: Barrel 2002-ini

  6. Data/MC comparison : Endcap unbalanced Short modules (HOT) Beside the Beam pipe (WARM) Th (MeV) Th (MeV) BEAM BEAM Y (cm) Y (cm) out of acceptance 2002-ini

  7. Data/MC comparison : Endcap COLD Th (MeV) 2002-ini Y (cm)

  8. Data/MC comparison for charged pions (KSp+p-) The effective threshold is computed on clusters associated to charged pion tracks (well separated pion clusters + unbiasing procedure) Th (MeV) NB: the threshold have been calibrated on photons 2002-ini Z (cm)

  9. Data/MC relative spread: photons on barrel Th (MeV) 2002-end 2002-ini 10% band Z (cm)

  10. Data/MC relative spread: photons on HOT sectors 2002-end 10% band 2002-ini

  11. Data/MC relative spread: photons on WARM sectors 2002-end 10% band 2002-ini

  12. Data/MC relative spread: pions on barrel 2002-end 2002-ini 10% band

  13. MC efficiency spread for a +/- 5% overall threshold drift p0p0p0 KSp0p0 p+p-p0 d 0.5% Ke3 Km3 KL decay

  14. MC efficiency spread for a +/- 5% overall threshold drift KSp+p- p0p0p0 p+p-p0 d 1% Ke3 Km3 KL decay

  15. Photon probability to fire the fifth plane A better tuning is needed if the T3 filter has to be simulated...

  16. DC trigger: T2D effective threshold • No hardware monitor on the • superlayer response (MC tuning can be performed only on the global trigger decision ) • T2D decision is processed after 1.3ms of integration (also in the simulation) • The ADC counts from the hardware monitor of the CAFFE board are not easily translated into a number of hits •  the T2D responseis correlated with the total number of reconstructed hits •  it is important to take into account the charged BKG • (gg events + insert module) e (T2D) KSp+p- MC K+K- MC + bkg DC hits

  17. MC + different bkg samples e (T2D) fixed MC th For each period ~1 pb-1 of gg events has been filtered to get the charged BKG sample. DC hits

  18. data/MC comparison: 2002-end sample e (T2D) A single T2D threshold value (72 hits within 1.3 ms) fits approximately both the neutral and charged kaon efficiency profiles DC hits

  19. data/MC comparison: 2002-ini sample e (T2D) The same T2D threshold is applied to the different samples (as in the real hardware maps) DC hits

  20. data/MC comparison: 2001 sample e (T2D) DC hits

  21. hardware/bkg/calibration stability Th(data) Th(data) - Th(MC) 2001 2002 2001 2002 RMS kpm = 2.5 RMS k0 = 1.9

  22. ± 2 ± 2 ± 1 Effective Threshold vs T2D Threshold (MC)

  23. MC efficiency spread for ± 1 hit threshold shift Th D K+K- 75.0% 2.4% KSKL 60.6% 1.3% KSp+p- KLpen87.9% 0.7% KLpmn 87.7% 0.7% KLp+ p- p087.0% 0.7% p-p+p062.5% 3.2%

More Related