EMCAL Offline Software

1. EMCAL Offline Software J.L. Klay Lawrence Livermore National Lab ALICE-EMCAL

2. Current Status Most of the infrastructure is complete and preliminary algorithms for the reconstruction are in place. Particle identification software and the calibration procedures/database interface code need more manpower. The offline software is being developed by a small team that is currently co-managed by Gustavo Conesa Balbastre at Frascati and Jennifer Klay at LLNL, with Bill Mayes of University of Houston serving as Calibrations Coordinator. We have a dedicated discussion list (alice-emcal-offline@cern.ch) and (semi-)monthly teleconferences. More dedicated manpower is needed now to move the effort forward at a pace that will allow the fast turnaround from first data to first physics. Some of the current players: Alberto Pulvirenti, Guenole Bourdaud, Cynthia Hadjidakis, Gustavo Conesa, Jenn Klay, Joern Putschke, Magali Estienne, Alexei Pavlinov, Marco van Leeuween, others… ALICE-EMCAL

3. Geometry • A mostly final geometry has been implemented, subject to minor modifications as the new prototype is developed. • Geometry software is complete and workable for now. • 10+2x0.5 Supermodule EMCal is included in the PDC06 simulations (“Trd1”) Documentation of EMCal setup and some accessor methods still to be completed ALICE-EMCAL

4. Data Structures • EMCal data structures for raw, reconstructed and event summary data (ESD) have been defined and are in use within the PDC06. • ESD has reconstructed clusters and “Pseudoclusters”, which are structures that hold all tower ADC info for EMCal -- re-calibration, jet energy backgrounds, etc. • ALICE would like us to utilize root-ized data structures for future testbeam and cosmic calibrations • Final raw data structures must be defined and the mapping of raw data stream to offline structures (electronics channel number to ALICE offline numbering) has not yet been implemented. • Data I/O adheres to ALICE standards. ALICE-EMCAL

5. Simulation • Simple creation of detector digits from simulated hits is implemented. (Hits2Digits, Hits2SDigits) • Once the electronics are finalized, the APD and FEE response parameters must be applied to correctly transform simulated hits to detector digits. • Algorithm to convert simulated digits to raw data format for full reconstruction has been implemented. (Digits2Raw) • How do we want to incorporate embedded simulated signals with raw data? (“Raw2SDigits”) ALICE-EMCAL

6. Alignment • Alignment data for the supermodule locations has been implemented with placeholders to be replaced by survey data after installation. • Code for testing reconstruction from misaligned supermodules in simulations is implemented. • Updates to utilize global alignment algorithms (AliAlignObj, etc.) to be checked in soon (JLK). ALICE-EMCAL

7. Calibrations • EMCal calibration data requirements and parameter sources defined and submitted to the ALICE Offline Board. • Pedestals • Energy scale from physics (MIP, electron pi0) • Relative tower gain from LED • Environmental variables (APD voltage, Temperature, etc.) • Calibration data structures for pedestal/energy calibration have been defined with placeholder values. • Connection with the ALICE online and database framework (SHUTTLE) have not yet been initiated, but volunteer (Gustavo) will start work on it soon. • No calibration strategies nor procedures to derive real constants from data have yet been defined or implemented. ALICE-EMCAL

8. Trigger • Code to generate EMCal trigger signals (following PHOS) from data has been implemented. • Trigger performance should be studied with data from PDC06 and additional simulations of Pb+Pb collisions to optimize EMCal trigger definitions. Many synergies with PHOS have made EMCal software easier -- adapted code ALICE-EMCAL

9. Reconstruction • A first iteration EMCal clusterizer using nearest neighbor clustering has been implemented. • Reconstructed clusters are stored in the AliESD structure for analysis. • Pseudoclusters and “Clusterv1” available in ESD • Preliminary cluster/track matching is almost complete. Code will be checked in soon (~days) -- electron id/cluster matching studies should begin. • After testbeam studies of the final EMCAL design are complete, reconstruction of simulated data should be matched to testbeam results. ALICE-EMCAL

10. Particle Identification • Preliminary /hadron discrimination algorithm based on cluster size exists. • Cluster shape fitting for particle identification needs to be implemented and optimized. • Electron identification requires track matching, which is now nearly ready, volunteers? • Preliminary invariant mass algorithm for 0 identification is implemented, but cut optimization for different 0 opening angles/transverse momentum regions is still under study. Lots of PDC06 data to be evaluated… ALICE-EMCAL

11. Analysis • No simple analysis algorithms, e.g. such as for extracting particle spectra for RAA studies, have yet been attempted. • Cone jetfinder algorithm with background subtraction methods for heavy ion collisions has been written and detailed studies of the EMCal + fast ALICE tracking have been performed, more studies under way • Jet-splitting corrections for the cone jetfinder are done, further evaluation needed. • Evaluation of the performance of FastJet, a kT jetfinder based on geometric nearest neighbor clustering for large multiplicity environments, using the EMCAL clusters and ALICE tracking in the works, needs more people ALICE-EMCAL

12. What’s needed now (FY07)? • Reconstruction: • •Work on track matching, PID: electrons, /h discrimination, 0 finding with PDC06 data • Analysis: • • Get jetfinder ready for charged only analysis to be used with next year’s p+p data (use PDC06 data now) • • Work on electron analysis with ALICE tracking and TRD, study track-matching to EMCal clusters and electron tagging within jets with PDC06 data • Calibrations: • • Prepare for/analyze new testbeam data (also within AliRoot framework) • Prepare for cosmic calibrations: data in ALICE format and develop cosmic calibration software within AliRoot (avoid duplicated effort) • • Implement MIP calib placeholder tables/constants in DB using cosmic calibrations • • Implement tables/constants for dead areas, hot towers, etc. in DB with procedures/code for how to fill/use them • Simulations: • • EMCal embedding procedure within existing AliRoot framework • Trigger: • • Study trigger with PDC06 p+p data using existing software, revise as needed ALICE-EMCAL

13. User environment On pdsf, multiple software versions available to users: /common/alice/AliRoot old --> v4-04-11 pro --> v4-04-Release (PDC06) new --> v4-04-Rev-08 (PDC06 with updates/bug fixes) HEAD (updated nightly) /common/alice/geant3 v1-5 v1-6 /common/alice/fluka v2005-6 /common/alice/root v5-11-02 v5-11-06 v5-13-02 Picks the pro version by default To get ALICE environment: source /common/alice/alisetup.csh source /common/alice/alisetup.csh <version> source /common/alice/alisetup.csh <version> <wrkdir> Useful if you have your own development directory ALICE-EMCAL

14. What you’ll see: pc2602 57% source /common/alice/alisetup.csh ########################################### ------------>Welcome to ALICE<------------- Currently available software versions are: new-->v4-04-Rev-08 (Updated PDC06 release) pro-->v4-04-Release (PDC06 release) old-->v4-04-11 (Older stable release) HEAD (nightly rebuilt version) Please make sure your environment is set for =====>Scientific Linux (sl302)<====== ########################################### Setting up default ALICE environment <I>------------Info-----------------<I> Setting up the following environments: ROOT: /common/alice/root/v5-11-06 ALICE: /common/alice/AliRoot/pro ALIEN: /common/alice/alien FLUKA: /common/alice/fluka/v2005-6 GEANT3: /common/alice/geant3/v1-5/root_v5-11-06 CVSROOT: :pserver:cvs@alisoft.cern.ch:/soft/cvsroot <I>------------Info-----------------<I> pc2602 58% ALICE-EMCAL

15. Development option If you are going to write software for the EMCal, you’ll want to set up your own development area, but you don’t want to check out/compile all of AliRoot We have a development script that will help you set up a working area: source /common/alice/setupEMCALDev.csh <version> <wrkdir> You only need to do this once, then whenever you log in, just set up the environment to point to your working area: source /common/alice/alisetup.csh <version> <wrkdir> ALICE-EMCAL

16. setupEMCALDev.csh pc2602 51% cd work/test2/ pc2602 52% source /common/alice/setupEMCALDev.csh new . <I> Saving old LD_LIBRARY_PATH and PATH settings <I> Setting up base AliRoot version ########################################### ------------>Welcome to ALICE<------------- Currently available software versions are: new-->v4-04-Rev-08 (Updated PDC06 release) pro-->v4-04-Release (PDC06 release) old-->v4-04-11 (Older stable release) HEAD (nightly rebuilt version) Please make sure your environment is set for =====>Scientific Linux (sl302)<====== ########################################### <I>------------Info-----------------<I> Setting up the following environments: ROOT: /common/alice/root/v5-13-02 ALICE: /common/alice/AliRoot/new ALIEN: /common/alice/alien FLUKA: /common/alice/fluka/v2005-6 GEANT3: /common/alice/geant3/v1-6/root_v5-13-02 CVSROOT: :pserver:cvs@alisoft.cern.ch:/soft/cvsroot <I>------------Info-----------------<I> ALICE-EMCAL

17. setupEMCALDev.csh (cont’d.) <I> Creating the working directory <I> Linking all common AliRoot files here <I> Removing link for library (we need a local file here to contain the new EMCAL library) <I> Removing link for include (we need a local one here for clean compiling) <I> Removing link for bin, (we need a local copy of the aliroot executable) <I> Making a local bin directory <I> Removing the link to the CVS directory (we need a local one to check-out files) <I> Removing link to ALIROOT subdirectory (maybe this is not really necessary, but we do it just to be on the safe side) <I> Copying ALIROOT files from the local $ALICE_ROOT (or get from the cvs server afterward, of you prefer) chmod: failed to get attributes of `new': Too many levels of symbolic links <I> Removing link for EMCAL subdirectory (we need to put the real files here) <I> Copying EMCAL files from the local $ALICE_ROOT (or get from the cvs server afterward, if you prefer) <I> Creating library directory <I> Linking all common libraries here <I> Removing link to EMCAL library, we will compile our own <I> Fixing ALICE Environment variables ########################################### ------------>Welcome to ALICE<------------- Currently available software versions are: ALICE-EMCAL

18. setupEMCALDev.csh (cont’d.) new-->v4-04-Rev-08 (Updated PDC06 release) pro-->v4-04-Release (PDC06 release) old-->v4-04-11 (Older stable release) HEAD (nightly rebuilt version) Please make sure your environment is set for =====>Scientific Linux (sl302)<====== ########################################### <I>------------Info-----------------<I> Setting up the following environments: ROOT: /common/alice/root/v5-13-02 ALICE: /eliza5/alice/jklay/work/test2/new ALIEN: /common/alice/alien FLUKA: /common/alice/fluka/v2005-6 GEANT3: /common/alice/geant3/v1-6/root_v5-13-02 CVSROOT: :pserver:cvs@alisoft.cern.ch:/soft/cvsroot <I>------------Info-----------------<I> ############################################################################ Just cd to $ALICE_ROOT, compile with gmake, and type rehash. You should be all set. ############################################################################ pc2602 53% ALICE-EMCAL

19. AliRoot Resources • Peter Hristov (and others) have put together a document that can help you get started… • http://aliceinfo.cern.ch/Offline/AliRoot/primer.html • How to set up the detector configuration/Monte Carlo generator • How to run a simulation • How to do reconstruction • How to perform an analysis on the ESD (Event Summary Data) • The Offline webpages have also improved quite a bit and provide lots of details: • http://aliceinfo.cern.ch/Offline/ • And of course, there are the mailing lists: alice-emcal-offline@cern.ch, alice-off@cern.ch ALICE-EMCAL