Notes for geometry downloads.

The geometry may be accessed using the "download_geometry.py" script in the MAUS bin/utilities directory. This script downloads a set of GDML files from the Configuration database, and extracts a ParentGeometryFile in the MICE Module format. This file contains the magnetic field definitions and the reference to the top level GDML file to be used in the simulation. The detector geometry files are also translated into MICE Modules for the purpose of the reconstruction geometry and are similarly referenced in the ParentGeometryFile, but not accessed for the purpose of the construction of the simulation geometry.

Geometries can be downloaded by geometry ID number, by run number, or by extracting the "current" geometry. The geometry has a set of currents in the beam line and solenoid magnets consistent with a 6-200 MeV beam. When downloading a geometry consistent with a given run the beam line and cooling channel currents for that given run will also be downloaded and the currents will be read into the ParentGeometryFile. An example of this download is

$MAUS_ROOT_DIR/bin/utilities/download_geometry.py
            --geometry_download_by "run_number" 
            --geometry_download_run_number 7472

Other beam line settings can be easily accessed by use of the download by run number, however solenoid current are not yet accessible in this way. To alter solenoid currents a geometry must be downloaded by ID number, and a cooling channel tag must be supplied. An example download command is supplied below.

$MAUS_ROOT_DIR/bin/utilities/download_geometry.py 
               --geometry_download_by "id" 
               --geometry_download_id 72
               --geometry_download_coolingchannel_tag  “NoField" 
               --geometry_download_beamline_tag "6-200+M0" 

Geometry Descriptions

ID Run number range Valid Dates Technical Drawing MICE Notes Comment
162 7066 - 7185 20 June 2015 - 12 July 2015 TD-1189-3752.pdf 436, 458, 464, 468, 469 June running. Tracker volumes filled with air. Evacuated LH2 vessel in AFC
161 7186 - 7468 13 July 2015 - 7 Oct 2015 TD-1189-3752.pdf 458, 464, 469, 470, 471, 472 Positions of EMR, TOF2, KL corrected after July move. Tracker volumes filled with air. Evacuated LH2 vessel in AFC.
160 7469 - 7496 7 Oct 2015 - 12 Nov 2015 TD-1189-3752.pdf 458, 464, 469, 470, 471, 472 Positions of EMR, TOF2, KL corrected after July move. Tracker volumes filled with air. Evacuated LH2 vessel in AFC. Opera field map for 4T field included in geometry download (for maus > v1.4.0).
148 7507 - 7547 24 Nov 2015 - 7 Dec 2015 TD-1189-3752.pdf 458, 464, 469, 470, 477, 472 Position of TOF1 altered after fix to upstream helium volume. Tracker volumes filled with helium.
166 7548 - 7583 12 Dec 2015 - 17 Dec 2015 TD-1189-3752.pdf 458, 464, 469, 470, 477, 472 Xenon at STP placed in LH2 vessel within the AFC. Tracker volumes filled with helium.
167 7584 - 7591 17 Dec 2015 - 17 Dec 2015 TD-1189-3752.pdf 458, 464, 469, 470, 477, 472 LH2 vessel filled with He in AFC. Tracker volumes filled with helium.
168 7622 - 7708 23 Feb 2016 - 8 March 2016 TD-1189-3752.pdf 458, 464, 469, 481, 483, 484, 485, 486 Empty AFC. Tracker volumes filled with helium. LiH in Mice Modules but not in GDML.
165 7709 - 7876 11 March 2016 - 14 April 2016 TD-1189-3752.pdf 458, 464, 469, 481, 483, 484, 485, 486 LiH Disk in AFC. Tracker volumes filled with helium.
172 7928 - 27 June 2016 - TD-1189-3752.pdf 458, 464, 469, 483, 491, 490, 492, 494 Empty AFC. Detector, and AFC positions updated to match surveys.

Superseded geometry descriptions

ID Run number range Valid Dates Technical Drawing MICE Notes Comment
114 7066 - 7185 20 June 2015 - 12 July 2015 TD-1189-3752.pdf 436, 458, 464, 468, 469 June running. Tracker volumes filled with air. Evacuated LH2 vessel in AFC
115 7186 - 7468 13 July 2015 - 7 Oct 2015 TD-1189-3752.pdf 458, 464, 469, 470, 471, 472 Positions of EMR, TOF2, KL corrected after July move. Tracker volumes filled with air. Evacuated LH2 vessel in AFC.
116 7469 - 7496 7 Oct 2015 - 12 Nov 2015 TD-1189-3752.pdf 458, 464, 469, 470, 471, 472 Positions of EMR, TOF2, KL corrected after July move. Tracker volumes filled with air. Evacuated LH2 vessel in AFC. Opera field map for 4T field included in geometry download (for maus > v1.4.0).
120 7507 - 7547 24 Nov 2015 - 7 Dec 2015 TD-1189-3752.pdf 458, 464, 469, 470, 477, 472 Position of TOF1 altered after fix to upstream helium volume. Tracker volumes filled with helium.
121 7548 - 7583 12 Dec 2015 - 17 Dec 2015 TD-1189-3752.pdf 458, 464, 469, 470, 477, 472 Xenon at STP placed in LH2 vessel within the AFC. Tracker volumes filled with helium.
123 7584 - 7591 17 Dec 2015 - 17 Dec 2015 TD-1189-3752.pdf 458, 464, 469, 470, 477, 472 LH2 vessel filled with He in AFC. Tracker volumes filled with helium.

Notes from May 31 2016 Release

  • Change material of diffuser helium side window to 1mm aluminum from 3mm polycarbonate
  • Move Q8 20 cm upstream

Notes from April 29 2016 Release

  • Minor correction to the Maus Information file to allow the diffuser irises to appear in the geometry
  • Corrected the absorber definitions in the July, Oct, and Dec geometries.

Notes from April 5 2016 Release

Updates include

  • Corrections to the tracker position supplied by Francois (really introduced February 2015)
  • Corrections to the quad positions suggested and supplied by Francois.
  • Corrections to the Ckov and TOF materials (as supplied by Lucien and Durga)
  • Addition of Empty AFC and LiH absorber geometries with fits for positions of PID detectors based on surveys published 7 March 2016.

Notes from Dec. 21 2015 Release

Updates include

  • Corrections to the solenoid field positions and rotations as supplied by Victoria.
  • Corrections to the positions of the Trackers in the upstream and downstream solenoids as provided by Melissa.
  • Corrections to the Tracker wire plane definitions as provided by Chris Heidt.
  • Re-parametrization of the EMR GDML file to allow for the definition of sensitive detector volumes.
  • Re-ordering of the TOF planes as provided by Durga.
  • Minor correction to the survey fits in response to a bug found in the rotation matrix (with no significant impact to the results).

Notes from Feb. 23 2016 Release

Updates include

  • Corrections to the tracker planes to extend the wires to the full extent of the frame radius (from half).
  • Added alignment information for the trackers based on the analytical alignment of Francois Drielsma.
  • To be used under the assumption that the reconstruction uses the same rotation conventions as the simulation (see below discussion).

Geometry Validations

Beam line tags of interest in CDB

There will be occasions when the simulation calls for a specific setup in the beam line and it is not sufficient to use an existing run. The settings for these cases can be extracted from the CDB using the following tagged settings. A run that was set using the following settings is also provided as an example.

Tag Example Run Comment
PionReference-NoDS
RefRun w/DS
RefRun w/o DS
ToF-Calib-NoDS
ToF-Calib+150
ToF-Calib+300
270+NoDS
300+NoDS
3-140+M0 Lowest order 3 pi 140 MeV positive muon beam
3-200+M0 Lowest order 3 pi 200 MeV positive muon beam
3-240+M0 Lowest order 3 pi 240 MeV positive muon beam
6-140+M0 Lowest order 6 pi 140 MeV positive muon beam
6-200+M0 Lowest order 6 pi 200 MeV positive muon beam
6-240+M0 Lowest order 6 pi 240 MeV positive muon beam
10-140+M0 Lowest order 10 pi 140 MeV positive muon beam
10-200+M0 Lowest order 10 pi 200 MeV positive muon beam
10-240+M0 Lowest order 10 pi 240 MeV positive muon beam
6-200+M0_lowDS
6-200+M0_highDS
6-200+M0_lowD2
6-200+M0_highD2
6-200+MatchNoDiff1
6-200+Match1NoDiff1
6-200+M0-UpScan1
6-200+M0-UpScan2
6-200+M0-UpScan3
6-200+M0-UpScan4
6-200+M0-UpScan5
6-200+M0-UpScan6
6-200+M0-UpScan7
6-200+M0-UpScan8
6-200+M0-UpScan9
6-200+MatchDown1
6-200+MatchDown3_NoDS

Cooling Channel tags in the CDB

These are the tags for the cooling channel currents that are contained in the CDB.

Tag Example Run Comment
StepIV-Off
SSU-100A-22Sep2015
US-fullflip-DS-off-11Sept2015
SSU-ECE-07Oct2015
SSU-SSD-06pi200+solenoid
NoField
StepIV-06pi200+solenoid
fcu-sol+100-5Dec2015
FieldOff
half-current-DS-24July2015
153MeV-flip-DSM1-off
SSU-06pi200+solenoid

Regarding Rotations in the Global Coordinate System

The coordinate system in the geometry is taken from the surveyor's coordinates (rotating x to y, y to z, and z to x) such that z is in the beam line direction (toward the West wall), x is toward the South wall, and y is up. The origin is defined by an extrapolation to the centre of the beam line from a brass plate on the floor beneath D2. Rotations on the other hand are taken from the CLHEP code which is used by both GEANT4 and ROOT. In GEANT4 (and by extension MICE Modules) these right handed rotations are applied to the coordinate system of an object rather than the object itself, producing an apparent left handed rotation of objects. This system of rotations, if you consider the Tait-Bryan rotation angles of theta_y (yaw) theta_x (pitch) and theta_z (roll), will produce anti-clockwise rotations of an object about the axis (when viewed in the axis direction) when a positive rotation is applied. The figure below illustrates this point using four sets of arrows defining a coordinate system with short arrow representing the x direction and the long arrow representing the z direction when no rotations are applied. The figure was generated using a GDML file with GEANT4 by applying rotations of 30 degrees along each rotation axis, as labelled.

g4_rotation_angles.png (25.8 kB) Bayes, Ryan, 22 January 2016 10:17

TD-1189-3752.pdf (97.5 kB) Bayes, Ryan, 28 January 2016 09:52