HCAL DPG News Sunanda Banerjee – SINP Olga Kodolova – SINP MSU June 7, 2012 June, 7 HCAL General S. Banerjee, O. Kodolova

HBHE drift from 2011 to 2012 HCAL General Meeting June, 7

PMT gain loss in 2012 We prepared chain for per week LED corrections but, seems, drift start to be slower PMT gain drop ~3% per 1/fb For the first 2012 week Multianode PMT are stable. HCAL General Meeting June, 7

Radiation damages HCAL General Meeting June, 7

Phi-symmetry HF calibration (2012) Without 29, 41 With 29, 41 Calibration group - HF rings are phi-symmetric within 2% - results of intercalibration doesn't allow to improve something - indications that precision of Iterative method in 2012 is worse w.r.t. 2011 HCAL General Meeting June, 7

Z->ee correction Need to account for possible radiation damage losses in HF LHC providing lots of data (20 fb this year ?) - 3-4 calibration passes? 2012 trigger improvement - L1 seeding using ECAL only - ECAL+HF selection in HLT Clear evidence of Z->ee peak With 2012 first data (up to 20th of May HCAL General Meeting June, 7

Isolated tracks Re-examine the PU contamination in 2012 data Make adjustment to the trigger to ensure it can collect useful data in the 2012 environment and beyond HCAL General Meeting June, 7

HBHE timing PFG studies HCAL General Meeting June, 7

HO issues HO response correction file is generated and will be included after ICHEP PFG studies HCAL General Meeting June, 7

HF simulation Currently there are 3 options for HF simulation: Using shower library (cannot simulate PMT hits) Full Geant4 simulation (too time consuming) Hybrid parameterization (Geant4+Gflash/showerlibrary) Now introduce identical fiducial volume cut (gaps between the wedges and some non-existing fibre locations) for all three options Also introduce some aperture cut in the parameterized approach for photons from the non-EM component. Some differences in long. shower profile Investigation continues 1 TeV π־ 1 TeV e־ HCAL General Meeting June, 7 z (mm) z (mm)

Back-up HCAL General Meeting June, 7

Radiation damages in HF: fibers 2011 Only HFM 2012 Latest results confirm raddam observation In 2011 A.Volkov, D.Elumahov HCAL General Meeting June, 7

Consequences of HF losses PMT gain loss starts to be the issue and high voltage may need to be lowering – need to verify the effect of S/N change to jet/met reconstruction Request for MC samples with the 3 times gain change was ordered to estimate the effect on the jet/met reconstruction Radiation damages of fibers need to be corrected. As rough estimation the sqrt of raddam measurement may be taken as the correction factor. HCAL General Meeting June, 7

Calibration procedure from 2011 to 2012 HPD and PMT gain drift HPD gain drift correction once per month (as in 2011) PMT gain drift correction once per week (roughly each ~1/fb) due to much higher degradation rate of gains in PMT (change w.r.t. 2011) HF Fibers degradation Radiation damage correction in HF based on the radiation damage measurements once per month (depends on the measurement) (change w.r.t. 2011) We consider HF is correctly calibrated with Z->ee corrections for the 2012 startup The above corrections as HcalGain condition IOV will be uploaded by creation to _express, _prompt and _offline tags and (by agreement) to _hlt tag HCAL General Meeting June, 7

Calibration procedure (continuation) phi-symmetry corrections with iterative and NZS method (as in 2011) during technical stops while the needed statistics is available Isolated track calibration (as in 2011) during technical technical stops while the needed statistics is available Absolute scale in HF with Z->ee corrections (Long fibers). Short fibers will be calibrated using Long fibers calibration and MC correction for ratio between Long and short taking into account RadDam estimation for Short fibers The above corrections as HcalRespCorrs condition IOV will be uploaded by approval to_express, _prompt, _offline and _hlt tags HCAL General Meeting June, 7

Sercan Sen, Lev Kheyn, Rahmat Rahmat HF simulation Sercan Sen, Lev Kheyn, Rahmat Rahmat Looks like better Performed Shower library then Gflash But dead zones in HF are not included More difference in Short fibers then in Long fibers Difference in eta Dependence between Data and MC seen In energy flow Overall problem: we do not have process that can calibrate Short fibers HCAL General Meeting June, 7

HBHE filter performance Alex Mott 1. HCAL Noise filters were deployed on MET paths last year (vetoing RBX noise flagged events with little other energy except RBX noise candidate) These filters started to be ineffective with increasing PU. 2. 2012: the new approach: try to remove the HCAL noise and evaluate the underlying event (underlying MET, for now) The behavior of filter with the first data is as expected: reduction of MET rates by 50-70%.. Need the provement that it is safe for physics. HCAL General Meeting June, 7

HO: ring0 + ring1 Including Ring0 and Ring1 improve slightly jet and MET resolution (talks from Gobinda and Caroline at the last HCAL DPG, 27th of April) Need to introduce HO both in PF and Calo Data certification for Ring0 and Ring1 started ChannelQuality status was updated yesterday/today to be included in 600pre4 for MC simulation with 530 HCAL General Meeting June, 7

LUT regeneration Recalibration was done with iterative and NZS methods Combined tag with coefficients was added as IOV to the Resp Corrections tag for LUT regeneration Pablo did LUT generation/Validation New LUTs were reported at L1 DPG and uploaded to DB before VdM scan (before 16th of April) HCAL General Meeting June, 7