LAr Conditions LAr ROD Test Beam Analysis These
LAr. Conditions, LAr. ROD & Test. Beam Analysis These Athena packages under LAr. Calorimeter have been used to run on testbeam data: LAr. Conditions : a service to fetch information from certain database LAr. ROD : simulates the Read-Out Driver to reconstruct energy, time and 2 for cells presented by Kin Yip 5 Dec. , 2001
LAr. Conditions written by Alexander Undrus at BNL “LAr. Conditions” is a service package for getting OFC’s, pedestals etc. from the database using MYSQL (for now) At present, the requested data from the database are loaded into the memory at the initialization stage of “LAr. Conditions” Available at the moment : 4 parameters of OFC’s, the pedestal averages and RMS’ and adc 2 gev constants “LAr. Conditions” provides various methods to retrieve from the memory the requested information access from both BNL and CERN machines successfully 5 Dec. , 2001
LAr. ROD FEB ROD LAr. Digit (ADC's) LAr. Raw. Channel (E, T, 2) The task is to convert ADC counts of several samples stored in the LAr. Digit to energies, times and 2’s ADCi = ADCi – pedestali Energy E = ai ADCi Time T = ( bi ADCi) / E Quality 2 = ADCi - ( gi E gi’ E T) 2 where ai, bi are the optimal filtering constants (OFC’s) and gi, gi’ are the waveforms 5 Dec. , 2001
LAr. ROD (cont. ) … further complication The responsible algorithm in LAr. ROD dealing with Test. Beam reads in the necessary calibration constants (maybe run dependent ) from a (MYSQL) database Saroj Kandasamy at BNL has filled in the database for us and she will continue to do whatever it is necessary Up to now, we have pedestal average/RMS, adc gev , and 4 optimal filtering constants stored in the “noisedb” at BNL, which can be read from everywhere LAr. ROD can convert ADC’s to energies in Ge. V with all the help from LAr. Conditions, in particular to adc gev conversion factors 5 Dec. , 2001
Test. Beam Energy from the LAr. ROD Run 208850 (year 2000), Beam energy at 99 Ge. V, =3, =10 No cuts of run/trigger/beamchamber information have been made (partly because they are not easily available from LAr. TBCnv) I can obtain some of the information from the relevant global variables but these are NOT the ideal way to do so the necessary “adc gev” applied 5 Dec. , 2001 Energies of the particular one cell at =3, =10 (middle layer) using med. gain
Some complications LAr. TBCnv itself seems unable to read most of the physics runs successfully in the 2001 Test. Beam due to problem of I/O format Saroj and I have hacked into the LAr. TBCnv codes and made quite a few modifications (by checking with emtblib) in order to read the 2001 testbeam data It is listed at: http: //www. phy. bnl. gov/~kinyip/athena/changes. htm Except run/event no. , run, trigger and beam chamber information (such as tdc/time, Random, adc_s 3) are NOT provided in the current versions of LAr. TBCnv It is necessary that we have the above-mentioned information to carry out real Test. Beam analysis On the detail side, eg. , for those “High. Med” runs (each cell appeared twice, one with high gain and one with median gain), we need to do something to select the cell with the “correct” gain for later analysis 5 Dec. , 2001
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