1 / 11

A Software Service Routine describing the Atlas Inner Detector Materials

A Software Service Routine describing the Atlas Inner Detector Materials. Steve Armstrong, Christian Hansen and Rikard Sandstr ö m November 2002, Uppsala This talk can be found at http://chansen.home.cern.ch/chansen/WORK/talks.html. Introduction - LHC.

phila
Download Presentation

A Software Service Routine describing the Atlas Inner Detector Materials

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. A Software Service Routine describing the Atlas Inner Detector Materials Steve Armstrong, Christian Hansen and Rikard Sandström November 2002, Uppsala This talk can be found at http://chansen.home.cern.ch/chansen/WORK/talks.html Christian Hansen, CERN

  2. Introduction - LHC The Large Hadron Collider (LHC) at CERN ATLAS, A Toroidal LHC ApparatuS Christian Hansen, CERN

  3. Introduction – Inner Tracker Measures the directions, momenta, and charge of particles produced in each proton-proton collision • Consists of three different systems • Pixel Detectors • Silicon Strip Detectors, SCT • Transition Radiation Tracker, TRT • All in a solenoidal magnetic field parallel to the beam axis Christian Hansen, CERN

  4. Introduction – Reconstruction 10 azimuthal positions from Pixel and Strip detectors (r < 50 cm) 36 azimuthal positions from TRT (50 cm < r < 100 cm) These signals are sorted into patterns produced by helical trajectories Then directions, momenta and charge for the particles are determined It is needed to select 1 interesting event out of 10 million background events The particle tracks can be distorted by the material of the detector For more accurate reconstruction the information about the material in the detector will be provided to the reconstruction packages by the Material Integration Service (MIS) Christian Hansen, CERN

  5. Introduction - MIS Material Information for ID is presently hard coded differently in various Reconstruction Packages Our goal is to provide a service reading from GEANT ID descriptions Christian Hansen, CERN

  6. Use of GEANT Example of a parameter set • User defined number of Geantinos sent out spherically (TRTSimG4, Zalite) 26. Production of a GeantinoMap: #179 < ProduceGeantinoMap = 1 > #180 < NbrOfGeantinoStepsInPhi = 10 > #181 < PhiMax = 90 > #182 < PhiMin = 0 > #183 < NbrOfGeantinoStepsInEta = 10 > #184 < EtaMax = 2.5 > #185 < EtaMin = 0. > • Geantinos take new StepPoint for each new material element encountered • For each StepPoint, RadiationLength is given from GEANT4 Christian Hansen, CERN

  7. VolumeElement Vs. GeantinoStep Approach VolumeElement (VE) Approach: GeantinoStep (GS) Approach: • ID is segmented into cylindrical VolumeElements (VE) • Each VE has an average RadiationLength ( X0 ) • User specified line between x1 and x2 intersects VEs and the x/X0 is determined • Suitable for fine spaced structures • In TRT used for wires, gas, straws, radiator and twistor • Geantinos take a new step for each new material • Each GS are saved with its RadiationLength ( X0 ) • The line between x1 and x2 has GS projected on to it and x/X0 is determined • Suitable for disjoint structures • in TRT used for support, module, SCTService and cooling Christian Hansen, CERN

  8. MIS – VolumeElement Approach • Each VE gets its average RadiationLength (X0j) from intersecting geantinos • Each VE gets the length that the line between x1 andx2 is intersecting it (xj) • The xj / X0j, for each intersected VE are summed together Christian Hansen, CERN

  9. MIS – The Geantino Step Approach • For large structures (like support) the GeantinoSteps and X0 are saved • GeantinoSteps are projected on to line between x1 andx2 Works in 3D!!! • RadiationLengthFraction between x1 andx2 is sum of ProjectionSteps (xi /X0i ) Christian Hansen, CERN

  10. PRELIMINARY!!! RadiationLengthFraction (x/X0)for TRT Step Approach An attempt to reproduce G4 values by the use of Step Approach and VolumeElement Approach Disagreement since the methods are under development VolumeElement Approach Christian Hansen, CERN

  11. MIS G4 G3 Muon Release Future Plans • Pixels: Working with Davide Costanzo’s G4Pixel • SCT: Plan to work with Andrea Dell’Acqua’s G4Sct • Continue to validate results (converting to G4) • Benchmark speed / optimize performance • Continuing to encounter substantial challenges using ATLSIM(Hope to continue work with Fred Luehring (TRT) and Pavel Nevski) • Have had nice discussions with Ada Farilla and Armin Nairz • Have given status tutorial of MIS to Armin • Difficult to assign dates – work preliminary • May not be possible to include in Release 5.0.0 • Everything in /afs/cern.ch/c/chansen/PUBLIC/ Draft to ATLAS note is being prepared and available : /afs/cern.ch/user/c/chansen/PUBLIC/MATERIALINTEGRATIONSERVICE/DOCUMENT/mis.tex Christian Hansen, CERN

More Related