T0 offline status

T0 offline status

Alla Maevskaya for T0 groupAlla Maevskaya for T0 group

INR RAS MoscowINR RAS Moscow

8 April 20088 April 2008

ALICE offline weekALICE offline week

OutlineOutline

T0 commissioning statusT0 commissioning status test February/March 2008test February/March 2008 calibration & reconstruction of runs calibration & reconstruction of runs collected during testcollected during test QAQAPlansPlans

Alla Maevskaya INR RAS ALICE offline week 8 April 2008

V0A

V0C

RB24

RB26

IP

37ps37ps37ps37psTime resolutionTime resolution

84.7884.7884.7884.78Active Active area(cmarea(cm22))

12121212# of channels# of channels

-2.9 to -2.9 to -3.3-3.3

4.5 to 4.5 to 5.05.0

h - coverageh - coverage

+70+70-350-350z-position(cm)z-position(cm)

T0-CT0-CT0-AT0-A

T0T0

T0-A T0-C

T0 detectorT0 detector

T0-C

Tatiana Karavicheva INR RAS CERN 1/04/ 2008

T0-CT0-C Installed (April 2007)Installed (April 2007) Tested with laser without Tested with laser without

magnetic field (December 2007)magnetic field (December 2007) Tested with L3 powered on 0.5 T Tested with L3 powered on 0.5 T

(February 2008)(February 2008) All hardware Installed All hardware Installed

(November 2007)(November 2007)


T0-A T0-A

Installed (February 2008)Installed (February 2008) Tested with laser with and Tested with laser with and

without magnetic field without magnetic field (February 2008)(February 2008)

All hardware InstalledAll hardware Installed

(January 2008)(January 2008)


Configuration of Hardware during the Configuration of Hardware during the February 2008 RunFebruary 2008 Run

T0-C & T0-A detector (24 modules) T0-C & T0-A detector (24 modules) Fast electronics (final version, apart from Fast electronics (final version, apart from

G&P generator module )G&P generator module ) Readout electronics (final version)Readout electronics (final version) Trigger electronics (final version)Trigger electronics (final version) HV / LV (final version)HV / LV (final version) LV (for readout crate)LV (for readout crate) Laser system (final version)Laser system (final version)


DCS/ECS/TriggerDCS/ECS/Trigger

T0 detector integrated in T0 detector integrated in ALICE DCS/ECS/TriggerALICE DCS/ECS/Trigger Global and standalone Global and standalone modes were used modes were used All trigger modesAll trigger modes (toggle, (toggle, signature, normal, random)signature, normal, random) were tested at P2 with CTPwere tested at P2 with CTP During global run not used During global run not used as trigger detector (from as trigger detector (from laserlaser)


Test Februrary/March 08Test Februrary/March 08

No data in GLOBAL runsNo data in GLOBAL runs

A lot of STANDALONE laser runsA lot of STANDALONE laser runsCalibration data was collected by DA and Calibration data was collected by DA and written in OCBD by Preprocessor.written in OCBD by Preprocessor.RAW and OCDB data registered in AlienRAW and OCDB data registered in Alien

MOOD monitoring MOOD monitoring


DA, PreprocessorDA, Preprocessor Two DAs: Two DAs:

T0Physda.cxx – equalizing channels T0Physda.cxx – equalizing channels

T0Laserda.cxx – walk correctionT0Laserda.cxx – walk correction Both set and configured on the Both set and configured on the

monitoring machinemonitoring machine Takes an input parameters file from Takes an input parameters file from

DAQDB (going to be changed before DAQDB (going to be changed before next cosmic run)next cosmic run)

Sends an output file to the FXS with Sends an output file to the FXS with the corresponding file id. the corresponding file id.

Michal Oledzki University of Jyväskylä ALICE offline week 8 April 2008

DA, PreprocessorDA, Preprocessor AliT0PreprocessorCosmic AliT0PreprocessorCosmic Has been set up and was working Has been set up and was working

together with DAs. together with DAs. Modified to work only with Laser Modified to work only with Laser

Calibration System (also in global run)Calibration System (also in global run) Processes data from DAs and stores Processes data from DAs and stores

results in OCDB. results in OCDB. DCS part still missing, to be done DCS part still missing, to be done

before next cosmic run. before next cosmic run. see more in Michal presentation on Friday

Michal Oledzki University of Jyväskylä ALICE offline week 8 April 2008

Calibration : equalizing channelsCalibration : equalizing channelsT0Physda.cxx during Data Taking (Global Run).T0Physda.cxx during Data Taking (Global Run).DA collected histograms with CFDtime1 – CFD time on DA collected histograms with CFDtime1 – CFD time on each side each side Currently, the preprocessor gets the mean of these Currently, the preprocessor gets the mean of these histograms and writes it into OCDB to be used in histograms and writes it into OCDB to be used in reconstruction as the value of shift between channels for reconstruction as the value of shift between channels for equalizing.equalizing.

The preprocessor should fit histograms and write in the The preprocessor should fit histograms and write in the OCDB the mean, sigma and number of entries. But, OCDB the mean, sigma and number of entries. But, because of not fully tuned electronics, the fitting method because of not fully tuned electronics, the fitting method used previously (with TSpectrum) was not fully functional.used previously (with TSpectrum) was not fully functional.Some of these problems are already solved, others ( we Some of these problems are already solved, others ( we hope) will be solved before the Cosmic Run May08.hope) will be solved before the Cosmic Run May08.


Calibration: amplitude-time Calibration: amplitude-time correction correction

T0Laserda.cxx during Laser Calibration Runs.T0Laserda.cxx during Laser Calibration Runs.We can measure the amplitude in 2 ways: We can measure the amplitude in 2 ways: QTC (charge-time converter) and as the difference of time QTC (charge-time converter) and as the difference of time measurements by Constant Fraction Discriminator and measurements by Constant Fraction Discriminator and Leading Edge Discriminator (LED-CFD)Leading Edge Discriminator (LED-CFD)

1MIP1MIP1MIP1MIP

10 10 MIPsMIPs

10MIPs10MIPs

08000025068005.1008000025068005.10 08000025068005.1008000025068005.10


Calibration: results for mono-Calibration: results for mono-MIP(3mips) runMIP(3mips) run 08000025081005.1008000025081005.10


beforeQTC LED-CFDLED-CFD

Calibration results for multi-MIPs Calibration results for multi-MIPs (1-10 MIPs) run (1-10 MIPs) run

1MIP1MIP

10MIPs10MIPs 1MIP1MIP

10MIPs10MIPs

08000025068005.1008000025068005.10


beforebefore QTCQTC LED-CFDLED-CFD

ReconstructionReconstruction

Choose 1Choose 1stst on the A and C side on the A and C sideCalculate T0 = (TA+TC)/2Calculate T0 = (TA+TC)/2 vertex = (TA-TC)/2+(fdZonA-fdZonA)vertex = (TA-TC)/2+(fdZonA-fdZonA)AliT0Reconstructor & AliT0Calibrator have 2 options : AliT0Reconstructor & AliT0Calibrator have 2 options : pdc and cosmicpdc and cosmic

ESDESD24 Time (UInt) 24 Time (UInt) 24 Amplitude (Float) will be in “MIPs” unit 24 Amplitude (Float) will be in “MIPs” unit T0 (UInt)T0 (UInt)Vertex (Float)Vertex (Float)


Reconstruction: mean time( T0)Reconstruction: mean time( T0)

mono-MIP multi-MIPsmono-MIP multi-MIPs


36ps 44ps

Reconstruction vertexReconstruction vertex

mono-MIP multi-MIPs


Survey data into alignment objectSurvey data into alignment object Alignment class (AliT0Align):Alignment class (AliT0Align):

• T0-C alignment based on survey dataT0-C alignment based on survey data

•Read data from survey (GRID)Read data from survey (GRID)

•Calculate x,y,z for T0Calculate x,y,z for T0

•Create AliAlignObjCreate AliAlignObj

•Store AliAlignObj to OCDBStore AliAlignObj to OCDB

T0-A to be surveyed at the end of April 2008T0-A to be surveyed at the end of April 2008

•storing fake survey datastoring fake survey data

•storing real survey data as soon as available storing real survey data as soon as available

T0 AlignmentT0 Alignment

Tomasz Malkiewicz University of Jyväskylä ALICE offline week 8 April 2008

Clearance around alignable volumesClearance around alignable volumes

T0 Alignment cont. T0 Alignment cont.

Removing all T0 overlaps (precision 0.01 [cm])Removing all T0 overlaps (precision 0.01 [cm])

Correcting macro MakeT0FullMisAlignment to properly store Correcting macro MakeT0FullMisAlignment to properly store misaligned objectsmisaligned objects

Shifts in T0 geometryShifts in T0 geometry

max shift in cm w.r.t. Global RS:max shift in cm w.r.t. Global RS:

sigmatr = 0.05sigmatr = 0.05

max rot in degrees w.r.t. Global RS:max rot in degrees w.r.t. Global RS:

sigmarot = 0.3sigmarot = 0.3

For T0 alignable volumes (24 PMTs, 12 on A- and 12 on C-For T0 alignable volumes (24 PMTs, 12 on A- and 12 on C-side) with no overlaps in the ideal geometry, there are no side) with no overlaps in the ideal geometry, there are no newly created overlaps by misaligning the volumesnewly created overlaps by misaligning the volumes

Tomasz Malkiewicz University of Jyväskylä ALICE offline week 8 April 2008

QA RAWQA RAW

QA RAW based on AMORE under construction:QA RAW based on AMORE under construction:AliT0QArec full set of needed histogramsAliT0QArec full set of needed histograms

During physics run we can take data with calibration During physics run we can take data with calibration trigger with laser data tuned on fixed amplitude.trigger with laser data tuned on fixed amplitude.Time, amplitude and T0 peaks position should be the Time, amplitude and T0 peaks position should be the same as in reference data. same as in reference data. Efficiency of each detector module should be stable.Efficiency of each detector module should be stable.

11stst prototype will be ready before Friday prototype will be ready before Friday


QA RecPointQA RecPoint Comparison between online and offline mean Comparison between online and offline mean

and vertexand vertex

Comparison between Time and Amplitude Comparison between Time and Amplitude spectra and reference spectra spectra and reference spectra

QA ESD

Comparison between amplitude measured by 2 methods


To be done - I:To be done - I:

Remove overlaps Remove overlaps before 11 Aprilbefore 11 April

Online Amore/QA Online Amore/QA next weeknext week

Update list of QA objects for what we really needUpdate list of QA objects for what we really need

Real QA with reference data Real QA with reference data


Do be done - IIDo be done - II

In time-amplitude correction procedure, improve In time-amplitude correction procedure, improve conversion of “time vs amplitude” histogram to calibration conversion of “time vs amplitude” histogram to calibration

TGraphTGraph next weeknext week

Add to the list of OCDB data table : position of peak for Add to the list of OCDB data table : position of peak for 1,2, 3… MIPs in amplitude spectra (DA & preprocessor 1,2, 3… MIPs in amplitude spectra (DA & preprocessor

type “Laser”)type “Laser”) next weeknext week

See Michal’s presentaion on FridaySee Michal’s presentaion on Friday

Write in ESD amplitude in “MIPs “ unitsWrite in ESD amplitude in “MIPs “ units next weeknext week


Documents

T0 offline status