hycal reconstruction: current situation current situation and future tasks. v. mochalov, ihep...

HyCal reconstruction:HyCal reconstruction: current situationcurrent situation and and future tasksfuture tasks..

V. Mochalov, V. Mochalov, IHEP (Protvino)IHEP (Protvino)

V. Mochalov. HyCal StatusV. Mochalov. HyCal Status 22July 29, 2005July 29, 2005

Part I. Calibration issuesPart I. Calibration issuesHyCal reconstruction codeHyCal reconstruction code

Cluster reconstructionCluster reconstructionTiming in HyCalTiming in HyCal

HyCal Energy CalibrationHyCal Energy CalibrationSnake Calibration and short term stabilitySnake Calibration and short term stabilityPhysics Calibration and long term stabilityPhysics Calibration and long term stability

HyCal position reconstructionHyCal position reconstructionMethodsMethodsInvestigationsInvestigations


Part II. Physics and planningPart II. Physics and planningPhysicsPhysics

StatusStatusMethodsMethodsDetector stabilityDetector stabilityRequired checks of the detectorRequired checks of the detectorRequired input information from other Required input information from other

sourcessourcesCalculation efficienciesCalculation efficiencies

PlanningPlanning


Cluster code doneCluster code doneMethods incorporated to the program Methods incorporated to the program

for Clusterfor Cluster3 different methods of coordinate 3 different methods of coordinate

reconstruction – reconstruction – I. LarinI. Larin ( (see Kelly talksee Kelly talk))Depth correction for coordinate reconstruction Depth correction for coordinate reconstruction

(photon shower) (photon shower) I. LarinI. LarinEnergy correction (from calibration) Energy correction (from calibration) I.LarinI.LarinIsland algorithmIsland algorithmDescription of the glass shower shapeDescription of the glass shower shapeMethod to calculate shower chi^2Method to calculate shower chi^2Shower leakage outside detectorShower leakage outside detector


Depth correction (Depth correction (IlyaIlya))


Energy correction (Energy correction (IlyaIlya))

Should be Should be recalculated recalculated because of because of new tagger new tagger calibration.calibration.


Glass shower shapeGlass shower shape


Cluster code to do.Cluster code to do. Cross-check of new cluster codeCross-check of new cluster code ( (DustinDustin)) Check Check shower leakage outsideshower leakage outside (recomendations (recomendations

from soft. techn.)from soft. techn.) Introduce shower leakage insideIntroduce shower leakage inside

Shower shape for PWO requiredShower shape for PWO required Study energy and coordinate reconstruction in Study energy and coordinate reconstruction in

transition regiontransition region Correction on beam angle and position Correction on beam angle and position Introduce leakage inside “holes”Introduce leakage inside “holes” Introduce “electron depth (and energy?) correction” Introduce “electron depth (and energy?) correction” Overlapping showers algorithm Overlapping showers algorithm


Timing in HyCal doneTiming in HyCal donePackage to reconstruct time for HyCal Package to reconstruct time for HyCal

triggers was developedtriggers was developed (Ilya, Dustin (Ilya, Dustin and Vasiliy)and Vasiliy)

Time calibrationTime calibration (Ilya and Dustin) (Ilya and Dustin)Functions to search Functions to search

Horizontal and vertical coincidenceHorizontal and vertical coincidenceClusters with the same timeClusters with the same timeCoincidence between Cluster and taggerCoincidence between Cluster and tagger


Pair hits in PWOPair hits in PWO


Timing calibration accuracyTiming calibration accuracy

Efficiency is Efficiency is small:small:


Timing links to doTiming links to doCross-check codeCross-check codeStudy and define all required Study and define all required

cutscutsStudy efficiency of the timing Study efficiency of the timing

reconstruction (and time reconstruction (and time offsets??) using snake offsets??) using snake calibration datacalibration data


Snake calibration statusSnake calibration status

Was done by Ilya Was done by Ilya for energy about for energy about 2 GeV2 GeV

Energy resolution Energy resolution about 1.7% about 1.7% (except ROC4) for (except ROC4) for PWO and 4% for PWO and 4% for glass.glass.

Close to expectedClose to expected But should be But should be

repeatedrepeated


Snake calibration to doSnake calibration to do

Repeat calibration due toRepeat calibration due to Take into account actual photon energy: Take into account actual photon energy:

New tagger calibration constantsNew tagger calibration constants electron beam energy (Hall C) electron beam energy (Hall C)

Take into account leakageTake into account leakage Use all energy range for calibrationUse all energy range for calibration

Repeat energy dependence Repeat energy dependence Final study of energy resolution using Final study of energy resolution using

calibration data, including dependence on calibration data, including dependence on beam energy, individual for channels ... beam energy, individual for channels ... (prepare all required for publication).(prepare all required for publication).


Short time stabilityShort time stability

Left – Left – IlyaIlya found the found the effect on LMSeffect on LMS

Possible pile-up Possible pile-up and rate and rate dependence dependence effect (effect (KellyKelly))

LMS LMS dependence dependence ((DustinDustin))


Long term stabilityLong term stabilityComparison of the first and second Comparison of the first and second

snake calibrations (electron and LMS) – snake calibrations (electron and LMS) – DustinDustin

LMS correctionLMS correctionCompton calibration data (Compton calibration data (ElenaElena))Single arm Compton for production runsSingle arm Compton for production runsPair productionPair productionpi-0 data pi-0 data


Compton conclusionsCompton conclusions Possibility to use calibration (resolution is Possibility to use calibration (resolution is

close to close to 1.7/sqrt(E)%)1.7/sqrt(E)%) Clearly seen changes on timeClearly seen changes on time Difference between photon and electron (need to Difference between photon and electron (need to

check using pair production)check using pair production) LMS is correlated, accuracy should be improvedLMS is correlated, accuracy should be improved

Final tagger reconstruction is required to finishFinal tagger reconstruction is required to finish Beam position and angle is required to finishBeam position and angle is required to finish Need to study possibility of Need to study possibility of single-arm single-arm

ComptonCompton Pair production calibration is very importantPair production calibration is very important


Position reconstructionPosition reconstruction3 different methods were introduced.3 different methods were introduced.Compton data showed the best result Compton data showed the best result

for logarithm method.for logarithm method.KellyKelly investigated 3 different methods investigated 3 different methods

for calibration datafor calibration dataDepth correction is done for photon – Depth correction is done for photon –

the same procedure is required for the same procedure is required for electronselectrons

Transition region study next month Transition region study next month


Physics statusPhysics status First version of skim files for pi0 is ready First version of skim files for pi0 is ready

(3.1M pi0's)(3.1M pi0's) Compton skim files: 2-nd versions is Compton skim files: 2-nd versions is

preparing preparing New versions will be created when final New versions will be created when final

bank structure will be prepared.bank structure will be prepared. Methods for correct mass and energy are Methods for correct mass and energy are

prepared prepared by Ilyaby Ilya Methods to calculate number of pi0 are Methods to calculate number of pi0 are

prepared prepared by Ilyaby Ilya


Energy and mass constraint Energy and mass constraint methods (methods (IlyaIlya))


pi-0 distributions (pi-0 distributions (IlyaIlya).).


Detector stability and Detector stability and required checksrequired checks

DAQ errors and it's recoveryDAQ errors and it's recoverySparcification cut investigation (Sparcification cut investigation (Nick's Nick's

talktalk))Bad/noisy channels (ADC's)Bad/noisy channels (ADC's)Trigger group stabilityTrigger group stabilityTrigger threshold and the stabilityTrigger threshold and the stability


Information required from Information required from other sourcesother sources

For calibration:For calibration:Actual electron beam energy-> tagger Actual electron beam energy-> tagger

energyenergyFor physics calibration and physicsFor physics calibration and physics

Beam position on the detectorBeam position on the detectorBeam position (and angle) on the targetBeam position (and angle) on the target

Information not used now:Information not used now:Slow control, including temperature and Slow control, including temperature and

humidityhumidity


Efficiency of the Efficiency of the reconstructionreconstruction

Trigger efficiency for whole detector Trigger efficiency for whole detector and each strip/quadrant on energyand each strip/quadrant on energy

Influence of the different cuts on Influence of the different cuts on reconstruction efficiency:reconstruction efficiency:Timing cuts;Timing cuts;Cluster energy cuts;Cluster energy cuts;Elasticity cuts;Elasticity cuts;......


Planning: Snake CalibrationPlanning: Snake Calibration

Preparation for final calibration:Preparation for final calibration: Finish tagger reconstruction – include beam Finish tagger reconstruction – include beam

energy (energy (Eric?)Eric?) Software (Leakage of the cluster):Software (Leakage of the cluster):

Prepare shower shape for PWO (Prepare shower shape for PWO (VasiliyVasiliy)) Investigate leakage procedure (see Investigate leakage procedure (see

recommendations from software technical recommendations from software technical meeting). meeting).

Add shower leakage inside calorimeter (Add shower leakage inside calorimeter (VasiliyVasiliy)) Add shower leakage to holes (Add shower leakage to holes (VasiliyVasiliy)) Find bad/noisy channels and describe them as Find bad/noisy channels and describe them as

holes (holes (who?)who?) Finish sparcification cuts (Finish sparcification cuts (Dustin?)Dustin?)


Planning: Snake Calibration Planning: Snake Calibration (ctd)(ctd)

Software (timing in the calorimeter) Software (timing in the calorimeter) Check time calibration for strips (quadrants)Check time calibration for strips (quadrants)Study and select time windows for clusterStudy and select time windows for cluster

Run final snake energy calibration for all energiesRun final snake energy calibration for all energies repeat energy dependencerepeat energy dependence for each channel for each channel

((Vasiliy+?)Vasiliy+?) Prepare Figures for publicationPrepare Figures for publication concerning concerning

energy resolution of the detector (energy resolution of the detector (VasiliyVasiliy)) LMS calibration (LMS calibration (??)) Study also the timing and trigger inefficiencies(Study also the timing and trigger inefficiencies(??) )


Compton calibration (Compton calibration (ElenaElena)) Preparations for final Compton calibration Preparations for final Compton calibration

procedure:procedure: Beam position and angle requiredBeam position and angle required !!! !!! Final tagger energy reconstructionFinal tagger energy reconstruction Software: add matrix inversion method.Software: add matrix inversion method.

Compton calibration coefficients for Compton Compton calibration coefficients for Compton data:data:

Comparison with snake calibrationComparison with snake calibration Comparison of the LMS and Compton calibrationComparison of the LMS and Compton calibration Compare different coordinate reconstruction methodsCompare different coordinate reconstruction methods

Single arm Compton Calibration on Compton (and Single arm Compton Calibration on Compton (and production!?) runsproduction!?) runs

Pair production calibration is required (Pair production calibration is required (who ?!!!who ?!!! ) )


Physics planningPhysics planning Software:Software:

Finish coordinate reconstruction procedureFinish coordinate reconstruction procedure Transition region coordinateTransition region coordinate

DAQ errorsDAQ errors Study all possible inefficiencies in Study all possible inefficiencies in

reconstructionreconstruction Compton cross-section (compare with theory)Compton cross-section (compare with theory)

Veto inefficiencyVeto inefficiency Single arm comptonSingle arm compton

Pair production cross-section (compare with Pair production cross-section (compare with theory)theory)


If compton and pair If compton and pair production production

are compatible with theory are compatible with theory we are ready we are ready

for for ππ00 data. data.

hycal reconstruction: current situation current situation and future tasks. v. mochalov, ihep...

Documents

hycal status

hycal timing

snake calibration status

repeat calibration

energy correction ilya

hycal triggers

larin energy correction

energy range