HCAL DPG Status

1. HCAL DPG Status Olga Kodolova Frank Chlebana HCAL General Meeting Apr 21, 2011

2. Current status • Done: • HCAL Calibration have been provided for CMSSW_4_2_0 • Response correction function to correct for HB channels • with missing LO filter • Online conditions have been updated • Rate of high energy hits have been reduced after HF sleeve • replacement • On going urgent tasks: • Migrating HF filters to HLT • Adding RBX/HPD noise filter in some MET trigger paths • Investigating methods to reduce L1 HF pre-triggering: apply BX-1 veto or/and develop L1 TP filters • Reducing Out Of Time pile-up

3. Calibration and condition status • 2011 startup conditions - done • ChannelQuality • Pedestals • HF gains after sleeve replacement • Response corrections with phisym (|ieta|<41) and scale (|ieta|<22-23) • Start of data taking with 3.11(4.1): • Included phi-symmetry in L1 and HLT+reco • Reprocessing with 4.2: • Include the full HCAL calibration at HLT and Reco; L1 will stay with phisym corrections • Caveat: iphi=-6, iphi=-32 • Special treatment for HLT and Reco. Response correction kept = 1 at L1.

4. L1 rate Constant Response correction for Problematic channels Iphi=-6 and Iphi=32 Note: at HLT and RECO we are using function to account for the missing neutral energy Filter at L0

5. Reconstruction and Calibration plans • Calibrations included for CMSSW4.2 • HBHE relative and absolute • HF relative • Postponed to the next release • HF absolute scale (Zee) • On going: improving calibration with higher statistics; CASTOR and ZDC calibration • Reconstruction (on going): • Minor changes in the definition of rechit bits • Unify strategy of rechit flags used for flagging noise • Include • More in: • https://twiki.cern.ch/twiki/bin/view/CMS/HcalDPG2011Tasks

6. Pre-triggering • Observe a rate from triggering in the BX-1 crossing • due to PMT window events . • Adjustment of HF signal position allows PMT • window events arriving in the earlier crossing • Possible solutions: • - Veto on BX-1 • Run 162929 looks very promising: 1 pre-triggered • event over 55794 • - L1 TP filters • Code exists but parameters need tuning and firmware requires • update. Filters rely on isolation may appear to be less effective • as occupancy increases and may disturb some physics channels

7. Pre-triggering (Jim)

8. Noise • Tuning HBHE noise filters in PU conditions from 75 ns->50ns. • First results looks promising but need extensive testing before making filters • default . • Plan to migrate HF noise filters (Topological and Pulse shape) to HLT • HF topological filter becomes less efficient with changing reconstruction from 4TS • to 2TS • HLT versions of Filters were presented to the TSG. • We prefer not to apply filters at HLT unless absolutely necessary • Some caveats: • Not RECO but AOD will be stored at Tier2-> access to TS may be • not possible unless we ask for HCAL DPG skim. • Today, after HCAL general we will have the • meeting dedicated HF noise sources

9. Out of time Pileup • Initial pileup discussion with Jetmet • https://indico.cern.ch/conferenceDisplay.py?confId=134118 • Jamboree • https://indico.cern.ch/conferenceDisplay.py?confId=134144 • Developments: • Change HBHE energy reconstruction from 4TS to 2TS • Develop filters to remove OOT pileup • Fit pulse shape train in TS2-TS9 • Plus pileup subtraction methods provided by JetMET. • Need to verify what option gives the best Jet and • MET resolution

10. HCAL Offline shifts • Shifts are on going in SINP MSU and FNAL on • daily basis.

11. HO Task force • Verify simulation of HO including SiPm • Evaluate HO usage for the different objects and • recommend appropriate reconstruction settings • Develop a calibration strategy of HO • Provide calibration constants for HO • In collaboration with JetMET demonstrate • improvements in jet reconstruction