Update README.md

sevdokim · shahor02 · commit cc5297b2e52c · 2021-09-24T20:57:43.000+02:00
diff --git a/Detectors/CPV/README.md b/Detectors/CPV/README.md
@@ -16,8 +16,8 @@ Triggered events are packed within each HeartBeatFrame. More info about data for
 
 ## Reconstruction
 The reconstruction is steered via [o2-cpv-reco-workflow](https://github.com/AliceO2Group/AliceO2/blob/dev/Detectors/CPV/workflow/src/cpv-reco-workflow.cxx) executable.
-#### First,
-it starts directly on FLP. Raw data is provided to [RawToDigitConverter](https://github.com/AliceO2Group/AliceO2/blob/dev/Detectors/CPV/workflow/src/RawToDigitConverterSpec.cxx) 
+#### 1. Raw to digits
+It starts directly on FLP. Raw data is provided to [RawToDigitConverter](https://github.com/AliceO2Group/AliceO2/blob/dev/Detectors/CPV/workflow/src/RawToDigitConverterSpec.cxx) 
 which converts raw format to cpv [digits](https://github.com/AliceO2Group/AliceO2/blob/dev/DataFormats/Detectors/CPV/include/DataFormatsCPV/Digit.h) and [trigger records](https://github.com/AliceO2Group/AliceO2/blob/dev/DataFormats/Detectors/CPV/include/DataFormatsCPV/TriggerRecord.h).
 Digits are calibrated objects: RawToDigitConverter reads 
 [pedestals](https://github.com/AliceO2Group/AliceO2/blob/dev/DataFormats/Detectors/CPV/include/DataFormatsCPV/Pedestals.h), 
@@ -32,20 +32,68 @@ o2-cpv-reco-workflow --input-type raw --output-type digits --disable-mc --disabl
 If there is no need to calibrate digits, add `--pedestal` flag to `o2-cpv-reco-workflow` then digit signal will be equal to raw amplitude. Such mode is used for pedestal calibration (see below).
 If you want to redirect stream of digits to root file then remove `--disable-root-output`.
 If you want to process MC and you need digits to be labeled according to corresponding primary particles then remove `--disable-mc` flag.
+Raw decoding itself is done by [RawDecoder](https://github.com/AliceO2Group/AliceO2/blob/dev/Detectors/CPV/reconstruction/include/CPVReconstruction/RawDecoder.h) class.
 
-#### Second, 
-output of previous command is stream of digits and triggers records. It's expected that the stream from FLP goes to EPNs where clusterization procedure is expected to run.
+#### 2. Digits to clusters
+Output of previous command is stream of digits and triggers records. It's expected that the stream from FLP goes to EPNs where clusterization procedure is expected to run.
 Clusterization is also steered by `o2-cpv-reco-workflow` executable. In order to run clusterization on digits, run 
 ```shell
 o2-cpv-reco-workflow --input-type digits --output-type clusters --disable-mc --disable-root-output
 ```
-The output of the command is stream of [clusters](https://github.com/AliceO2Group/AliceO2/blob/dev/DataFormats/Detectors/CPV/include/DataFormatsCPV/Cluster.h) and corresponding trigger records.
-Then clusters are ready to be compressed to CTF and to be keeped on storage. 
+The output of the command is stream of [clusters](https://github.com/AliceO2Group/AliceO2/blob/dev/DataFormats/Detectors/CPV/include/DataFormatsCPV/Cluster.h) and corresponding trigger records. Clusterization is done by [Clusterer](https://github.com/AliceO2Group/AliceO2/blob/dev/Detectors/CPV/reconstruction/include/CPVReconstruction/Clusterer.h) class.
+
+#### 3. Clusters to CTF
+Then clusters are ready to be compressed to Compressed Time Frame and to be kept at storage. Try to convert  
+<!-- add here info how to run CTF creator -->
+
 
 ## Simulation
+Simulation is organized as follows: 
+#### 1. Creation of hits
+[Hits](https://github.com/AliceO2Group/AliceO2/blob/dev/DataFormats/Detectors/CPV/include/DataFormatsCPV/Hit.h) are objects which keep information about signals such as energy depositions created by single primary particles in detector channels. Hit creation is done by [Detector](https://github.com/AliceO2Group/AliceO2/blob/dev/Detectors/CPV/simulation/include/CPVSimulation/Detector.h) class. To run hits creation type 
+```shell
+ o2-sim -n10 -g boxgen --configKeyValues 'BoxGun.pdg=11 ; BoxGun.prange[0]=10.; BoxGun.prange[1]=15.; BoxGun.phirange[0]=260; BoxGun.phirange[1]=280; BoxGun.number=50; BoxGun.eta[0]=-0.125 ; BoxGun.eta[1]=0.125; ' -m CPV
+```
+This command will generate 10 events (`-n 10` option) with uniform particle generator (`-g boxgen` option) which generates 50 electrons (`BoxGun.number=50; BoxGun.pdg=11`) with flat momentum distribution in range from 10 GeV/c to 15 GeV/c (`BoxGun.prange[0]=10.; BoxGun.prange[1]=15.;`), flat azimuthal angle phi distribution in range from 260 to 280 degrees (`BoxGun.phirange[0]=260; BoxGun.phirange[1]=280;`), flat pseudorapidity distribution in range from -0.125 to 0.125 units (`BoxGun.eta[0]=-0.125 ; BoxGun.eta[1]=0.125;`), and finally hist only for CPV are created (`-m CPV`). Result of this command is file o2sim_HitsCPV.root containing hits and some other important stuff.
+
+#### 2. Hits to digits
+Hits from different primaries then needed to be merged and electronic noise to be added in order to obtain  digits from hits. This can be done with [Digitizer](https://github.com/AliceO2Group/AliceO2/blob/dev/Detectors/CPV/simulation/include/CPVSimulation/Digitizer.h) workflow. Run
+```shell
+o2-sim-digitizer-workflow --onlyDet CPV
+```
+in order to do so. It merges hits and adds electronic noise to merged signals. Electronic noise is simulated as 3 sigma pedestal jitter.  As a result the file 
+You can add `--configKeyValues 'CPVSimParams.mCCDBPath=localtest'` option in order to avoid connection to CCDB and use ideal pedestals (sigma = 1.5 ADC counts for all channels). You can also choose how much sigmas to use for noise simulation providing `--configKeyValues 'CPVSimParams.mZSnSigmas=X'` option, where X is floating point number.
+
+#### 3. Digits to raw
+Digits can be converted to raw data format using [RawWriter](https://github.com/AliceO2Group/AliceO2/blob/dev/Detectors/CPV/simulation/include/CPVSimulation/RawWriter.h) class. Try to run 
+```shell
+o2-cpv-digi2raw -o raw/CPV
+```
+This command will read digits from cpvdigits.root by default and produce raw/CPV/ folder with config and raw files. Digits to raw conversion is done by [RawWriter](https://github.com/AliceO2Group/AliceO2/blob/dev/Detectors/CPV/simulation/include/CPVSimulation/RawWriter.h) class. You can specify `--ccdb-url localtest` option in order to use dummy calibration. IMPORTANT is to use same CCDB path as you used at previous step i.e. hits to digits conversion. Input file also can be changed by providing `-i /path/to/file.root` option.
+
+
+Raw file is ready to be read as normal raw data file and be processed normally with full reconstruction chain like that:
+```shell
+o2-raw-file-reader-workflow --input-conf raw/CPV/CPVraw.cfg |  o2-cpv-reco-workflow --input-type raw --output-type digits --disable-mc --disable-root-output |  o2-cpv-reco-workflow --input-type digits --output-type clusters --disable-mc
+```
+
 
 ## Calibration
 
 ## Quality Conrol
 
 ## Local testing
+#### Simulation
+```shell
+o2-sim -n10 -g boxgen --configKeyValues 'BoxGun.pdg=11 ; BoxGun.prange[0]=10.; BoxGun.prange[1]=15.; BoxGun.phirange[0]=260; BoxGun.phirange[1]=280; BoxGun.number=50; BoxGun.eta[0]=-0.125 ; BoxGun.eta[1]=0.125; ' -m CPV
+o2-sim-digitizer-workflow   --onlyDet CPV #consider to add --configKeyValues 'CPVSimParams.mCCDBPath=localtest' to use ideal pedestals for noise simulation
+o2-cpv-digi2raw -o raw/CPV 
+```
+#### Reconstruction
+```shell
+o2-raw-file-reader-workflow --input-conf raw/CPV/CPVraw.cfg |  o2-cpv-reco-workflow --input-type raw --output-type digits --disable-mc --disable-root-output |  o2-cpv-reco-workflow --input-type digits --output-type clusters --disable-mc
+```
+#### Pedestal calibration
+```shell
+o2-raw-file-reader-workflow --input-conf CPVraw.cfg  | o2-cpv-reco-workflow --input-type raw --output-type digits --disable-mc --disable-root-output --pedestal | o2-calibration-cpv-calib-workflow --pedestals --max-delay 0 --tf-per-slot 100 | o2-calibration-ccdb-populator-workflow
+```
