MuonGeoModel

1
MuonGeoModel

• Available Tools
• Status

• Connection with the COOL
• Alignment (A-lines)
• Deformations (B-lines)

• Measurement surfaces
• Local-Global transforms

• Clashes
• Cutouts
• use of G4 Assemblies

2
MuonGeoModel

• Two layers in MuonGeoModel
• Raw Geometry for use in simulation
• (GeoPhys)Volume hierarchy materials
  tags/identifiers
• relative transforms
• some volumes (Detector Elements) cache full
  transforms
• deepest level in detector elements is the active
  gas volume
• some transforms are alignable
• Readout Geometry for use in reconstruction
• Detector Manager providing access to
• Detector Elements XxxReadoutElements
• provide access to readout granularity i.e. strip
  position
• Xxx Mdt multilayer
• Csc chamber layer
• Rpc module
• Tgc module
• MuonStations group of assembled Detector
  Elements with a common alignable transform

3
MuonGeoModel

• Clients of MuonGeoModel
• Simulation (Geant 4) via Geo2G4 -involves raw
  geometry-
• translates
• GeoPhysVolume tree into a G4 volume hierarchy
• Geo tags and identifiers into G4 volume names and
  copy numbers
• GeoTransforms into G4 transforms
• Digitization
• Data Preparation
• PrepRawData from RDO or from bytestream
• Services in the muon sw
• exceptions MdtCablingSvc, RpcCablingSvc
• Calibration
• Reconstruction
• exceptions MuonBoy related sw, MuFast (LVL2
  muon trigger)

-involve readout geometry-
4
MuonGeoModel

• Validation Tools Hit relocation
• test coherence between raw geometry and readout
  geometry
• Simulate geantino tracks
• hits hold an identifier Id (from G4 volume names
  copy numbers) and local coordinates Ploc in the
  sensitive volume frame
• Relocate geantino hits
• convert Ploc into a global position Pglob using
  Id and MuonGeoModel readout geometry
• Measure distance between Pglob and the geantino
  track (ideally 0)
• Code and python available in MuonSpectrometer/Muon
  GeoModelTest

10-6 mm
10-12 mm
5
MuonGeoModel

• Validation Tools AmdcMGM
• test coherence of geometry implementation in two
  independent models MuonGeoModel and Amdc
  assuming same primary numbers and definitions
• the flow
• ascii amdb (primary numbers)
• in oracle tables (via sql scripts) read by
  MuonGeoModel
• in oracle blob (dump) read by
  Amdc
• compute x,y,x of the centre of strips/wires
• compare x,y,z from GeoModel and x,y,z from Amdc
• for layout MuonSpectrometer-R-Light ? ? 0
• for layout MuonSpectrometer-R-Light-Egg-Rndm
  mostly 0, in some cases
• -under investigation- ? lt 30 microns
  (MuonboyAmdc performance OK on data simulated
  with MuonSpectrometer-R-Light-Egg-Rndm)

6
MuonGeoModel

• Graphic Tools
• HepVis very useful but with some limitations
  for complex shapes
• Volume Clash Diagnostic
• No built-in GeoModel diagnostic
• Geant4 recursive Geometry test very heavy
• Inert materials
• Barrel Toroid
• Endcap Toroids
• Feet
• Shielding
• Calorimeter Saddle (work in progress)
• No validation tools other than graphics

7
MuonGeoModel

• Alignment Constants
• Built-in GeoModel capability AlignableTransform
  NominalTransform x DeltaTransform
  
• MuonSpectrometer-R-Light-Egg-Rndm
• A-lines available in the static geometry DB
  along with P-lines
• Successful test of the implementation of
  DeltaTransforms from amdb conventions about
  A-line parameters
• Real life and Condition Data Challenge
• MuonGeoModel will get P-lines from the static
  geometry DB and A-lines from the Condition DB
  using the Interval of Validity Service in
  practice
• a Service ( a Tool) in MuonConditions/MuonCondUti
  ls provide methods to
• retrieve from the Cond.DB A-lines B-lines
  store them in StoreGate
• provide A-lines to the MuonGMMuonStations which
  update the DeltaTransform
• deployed for COOL 1.3 (atlas-rel. 12.0.5) under
  test in dev. for COOL 2.0(13.0.0)
• MuonGeoModel side ready
• These methods are registered to the IoV Service
  for call-back
• when a transition from one IoV to another occurs
  the methods are invoqued
• Data preparation and reconstruction will always
  get the updated geometry

8
MuonGeoModel

• Deformation Constants
• No Built-in GeoModel capability
• Access to B-lines from the Cond.DB can follow the
  same approach as for A-lines once B-lines
  are read, a pointer to them is assigned to the
  class describing the corresponding MDT multilayer
  - to be done (minimal intervention) -
• Use of B-lines in MuonGeoModel
• Too heavy implementing them in raw-geometry
• why simulating run-time conditions, other than
  for testing purposes ?
• a memory saving mechanism in GeoModel/G4 assumes
  a regular multilayer organization
• high risk of clashes
• Deformations must be treated in Readout Geometry
• a plan (under development and test) for
  deformations in MDT multi-layers only
• all deformations except wire sagging can be
  described with tilt and shift of individual tubes
  in the multilayer
• full MDT tube transform comes from (first to
  last)
• nominal (translations only) tube_to_multilayer
• delta_deformation - add tilt and shift in the
  multilayer frame (B-lines)
• nominal multilayer_to_station
• delta_station_alignement (A-lines)
• nominal station_to_global (P-lines)

9
MuonGeoModel

• Deformation Constants
• Deformations for reconstruction clients
• reconstruction typically uses
• tubePos() i.e. tube fullTransform applied to
  0,0,0
• transform(Identifier Id),
• surface(Identifier Id)
• normal(Identifier Id)
• which all use the tube full transform ? directly
  account for deformations
• wire-sagging will be handled in the RioCreators
  since SaggedLineSurfaces are associated to MDT
  tubes (under test in the MIG nightlies)
• Plans for testing deformations in Readout
  Geometry (including wire sagging)
• simulate single muons with a nominal geometry
  layout (R-light)
• digitize by emulating chamber distortions
• convert the hit local coordinates into nominal
  global coordinates ? point belonging to the track
• convert the global position into local
  coordinates in tilted and shifted tube (according
  to B-lines)
• use the new local coordinates to compute drift
  time
• reconstruct assuming B-lines
• code in the digitizers
• for handling wire sagging on demand available
  to be tested
• for other deformations on demand to be done
  easy once the implementation in MuonGeoModel is
  fully available

10
MuonGeoModel

• New Tracking Geometry interfaces
• surfaces, bounds, normals, center, transform(
  tube/strip dependent methods)
• Requested by generic track fitters and tracking
  (pattern recognition) tools
• all implemented (refinements needed for TGC phi
  strips)
• MDT
• from StraitLIneSurface with cylindrical bounds
  (working fine)
• to SaggedLineSurface ( SaggingLineDescriptor)
  with cylindrical bounds per each tube
• optimize the number of descriptors needs
  testing
• RPC
• PlaneSurface with rectangular bounds per gas-gap
  and per view (first local coord. is the one
  measured) parallel strips - OK
• CSC
• PlaneSurface with trapezoidal bounds per
  gas-gap and per view parallel strips OK
• TGC
• PlaneSurface with trapezoidal bounds per gas-gap
  and per view parallel wire-gangs BUT almost
  pointing phi strips ? measuring phi, not local
  cartesian x
• An option under study use a disc surface with
  trapezoidal bounds for phi-surfaces
• some work needed in the new tracking geometry
  primitives

11
MuonGeoModel

• Volume Clashes in MuonGeoModel
• discussed in more detail in the Simulation Report
• HERE try to categorize the reasons and outline
  general solutions
• Wrong implementation of primary numbers no much
  to do other than adding man-power
• Cutouts in the station mother volume
• Missing description of cutouts
• Cutouts in Amdb are described for station
  components
• in MuonGeoModel can be implemented with boolean
  operations
• BUT must be propagated to
• the embedding station mother volume
• all child volumes in the hierarchy
• implemented only in BOG otherwise conflicting
  with the ATLAS feet
• special description of the multilayers
  (sub-multilayers of different length)
• cutouts propagated, by hand, to the station
  mother volume
• no other station components affected

12
MuonGeoModel

• Actions in GeoModel
• allow to perform some operation in a recursive
  way on a geometry tree
• under development a kernel action to treat
  cutouts (subtract recursively a shape from all
  volumes in a tree)
• strictly needed to describe cutouts involving
  several components in a station BMS, BMF, etc.
• Geant4 Assemblies
• groups of volumes linked by a common transform
  (without an envelop)
• Geo2G4 translates GeoPhysVolumes with material
  Ether into G4 Assemblies
• would be ideal for stations
• no need to propagate component cutouts to the
  embedding station
• a switch to use assemblies for (some) stations in
  MuonGeoModel - done
• assemblies for stations need a new identification
  scheme to be shared by MuonGeoModel and G4
  Sensitive Detectors done
• Memory allocated per event by the simulation of
  the Muon Spectrometer
• standard (no assemblies) 390 MByte
• assemblies for all stations 600
  MByte (unfeasible)
• assemblies for BOG with cutouts 394 MByte -
  done

13
MuonGeoModelgeneral status

• OK for active elements
• almost missing for dead materials

• work in progress
• no show-stoppers foreseen

• almost there
• optimize TGC phi view

to do all new dead material blocks

• clean up clashes
• Cutouts from a general tool