The ATLAS Tiles Hadronic Calorimeter

1. The ATLAS Tiles Hadronic Calorimeter Status Of: Construction Testing Calibration Irene Vichou, UoA Irene Vichou, HEP2003, Athens(GR)

2. Layout of the Talk • Description of the TileCal detector • Role in ATLAS • Performance issues • Achievements on the construction • Mechanics / Optics • Electronics • Pre-assembly • Calibration and Testing • Relevant performance • Steps that we still have to climb… Irene Vichou, HEP2003, Athens(GR)

3. The TileCal detector in ATLAS • Sampling Fe/Scintillator • 3 cylinders of 64 modules • Dimensions • Total weight 2900 T 64x(B~21 T / EB~11 T) • ~10K r/o channels • |h| coverage up to 1.7 R=4.3m BARREL EB R=2.3m 5.6m 2.9m Irene Vichou, HEP2003, Athens(GR)

4. TileCal principle PMT fibre tiles • Steel/Scintillating tiles and fibres • Thickness of Steel:4mm, Tile:3mm • 11 tiles radially read by 2 fibres • Segmentation easy by construction • Dh x Df = 0.1 x 0.1 • 3 radial samplings (1.4,4.0,1.8 l at h=0 ) • Good hermeticity • Nice solution for housing electronics One TileCal Module Irene Vichou, HEP2003, Athens(GR)

5. Performance issues: Energy resolution Linearity 1%-2% from few GeV to ~TeV S/N for m’s Overall ~6 (digital electronics) 3rd sampling ~2 ( for LVL1 analogue sums) Role of TileCal: Reconstruct the energy and direction of jets and hadrons Contribute to the ETmiss measurement Assist to the e/g identification (leakage cut) Help in m identification (clean signal in 3rd sampling) Monitor the luminosity by the minimum bias events current TileCal hadronic calorimeter Irene Vichou, HEP2003, Athens(GR)

6. TileCal construction (mechanics and optics) • The detector consists of 3 cylinders of 64 modules each. • All modules are constructed and instrumented optically!! Finished! Materials from 10 institutes • Delicate procedure! Optical elements per module: • 3355 (1852) tiles for a Barrel (Ext. Barrel) • Number of fibres is twice the above • 26 to 92 fibres read by a PMT Irene Vichou, HEP2003, Athens(GR)

7. TileCal Instrumentation A barrel module during optics instrumentation with tiles and fibres Irene Vichou, HEP2003, Athens(GR)

8. TileCal Modules stored Building 175 Building 185 All modules arrive at CERN for cylinder pre-assembly Irene Vichou, HEP2003, Athens(GR)

9. Optics Quality Control One readout cell All individual optical components are “seen” in this shadowgram. • A hydraulically driven Cs source system scans the cells • The individual optics elements responses are extracted • Their uniformity should be < 10% Irene Vichou, HEP2003, Athens(GR)

10. Optics Quality Results Uniformity of optics response inside a cell (goal was 10%) 7% Barrel Modules Ext. Barrel Modules 7% Irene Vichou, HEP2003, Athens(GR)

11. Preassembly of Ext. Barrel • Started in Nov 2002 and finished 3 days ago! • Reasons to pre-assemble: • Test the assembly, develop and use tooling • Correct positioning, study deformations • Steps ready to repeat in the pit • Next steps: • Dis-assemble the cylinder except 18 base modules (they will be lowered on their cradle in the ATLAS pit) • Do the same for the other two cylinders • Test dummy weight of the cryostat inside TileCal Irene Vichou, HEP2003, Athens(GR)

12. Ext. Barrel Cylinder Webcam image of the pre-assembly 3 days ago !!! Irene Vichou, HEP2003, Athens(GR)

13. The Ext. Barrel cylinder pre-assembly Ext. Barrel Cylinder Height :8.5 m Weight ~700 T Irene Vichou, HEP2003, Athens(GR)

14. Mixer Laser PMT PMT Block Divider 3-in-1 L H Mother Board Digitiser Drawer ADC Integrator Adder Optical Link Interface ROD DC Calibrations TTC TileCal Electronics Particles from detector On detector Pulse calibration Cs, MinBias particles External µ Trigger Hadron Trigger Energy Irene Vichou, HEP2003, Athens(GR)

15. Drawer Electronics Readout electronics HV distributor PMT block Assembled/tested in Athens Irene Vichou, HEP2003, Athens(GR)

16. Status of electronics • PMT Blocks (10000 in total) • 45% produced and tested at the University of Athens(materials coming from 10 other labs) • Drawers production • Series assembly just started in France • All components are available in time for production • Digitizers and Adders have started being produced in series. • External electronics • R&D almost finished, final kick-off next year (RODs, optical links) Drawers getting ready for the Barrel pre-assembly Very strict QC protocols are applied in testing our electronics either individually or in assemblies! Irene Vichou, HEP2003, Athens(GR)

17. Particle beam tests Setup for testbeam calibration e, m e, m, p • This is where the detector becomes “alive”: • TileCal tested together with ATLAS r/o and DAQ components • 1 out of 8 modules exposed • set the EM scale of the cells (pCb/GeV value) • check the uniformity • transfer of mip m’s response via Cs data across detector • setup trigger conditions • optimise hardware settings, e.g timing • test E,t reconstruction algorithms Irene Vichou, HEP2003, Athens(GR)

18. Highlights from testbeam • Electrons at 90o, pCb/GeV values in different modules: • Applied optimal filtering in pulse reconstruction online (for ROD): • improvement in E resolution by 15% for p’s • Tested m reconstruction efficiency in last sampling to assist in the LVL1 trigger (complementary to m system) • This is the last year of calibration for TileCal. • Next year’s run is combined with the EM calorimeter, including tests • at very low energies (~1 GeV). Irene Vichou, HEP2003, Athens(GR)

19. Muons Electrons Pions Simulation: use of Geant4 G3 vs G4 vs testbeam data G4 is closer to TileCal testbeam data, but improvements are expected Irene Vichou, HEP2003, Athens(GR)

20. Next important step • Certification, Calibration of Barrel modules: • Test modules equipped with electronics • Use final ATLAS r/o and DAQ hardware • Set their final operating conditions (HV, gains etc) • Store the constants in a final database for ATLAS use • Preassembly of the cylinder • Run the Cs source in full scale TileCal This will be a useful testbench on how to commission and operate the detector! It’s a complicated project and a working group is already in place. Irene Vichou, HEP2003, Athens(GR)

21. Area for certification CERN, B175 Clean area for certification and preparation Control Rooms Irene Vichou, HEP2003, Athens(GR)

22. The University of Athens ATLAS TileCal Group Members: Antonaki A., Fassouliotis D., Giakoumopoulou V., Giokaris N., Lembesi M., Manousakis A., Morphi M., Tatsis S., Tzanakos G., Vichou I. Responsibilities are: PMT blocks assembly, test and characterization Participation in: • Certification and calibration procedure: • Cs source monitoring system • Database development for final certification results • Performance studies: • Jet absolute energy scale calibration Irene Vichou, HEP2003, Athens(GR)

23. Conclusions and Outlook Up to now: • The detector construction has finished. • The pre-assembly of one wheel was successfully completed! • The performance of TileCal is well understood with testbeam and Monte-Carlo. • Electronics production is under control. Near future: • Equip all modules with electronics • Finish testbeam calibration this summer • Pre-assemble barrel and 2nd Ext. Barrel cylinder and practice on how to commission TileCal • Start assembly in the pit (mid-2004) More distant future: • Commissioning in the pit • Well-known physics to check the detector (LHC start) • Ready for more exciting physics! Irene Vichou, HEP2003, Athens(GR)