Feature #509

Tracker Geometry

Added by Tunnell, Christopher almost 13 years ago. Updated over 11 years ago.

Target version:
Start date:
20 June 2011
Due date:
% Done:


Estimated time:


Somebody needs to write a description of the tracker MICE modules and the SCiFiDoubletParams and SciFiPlane to make sure the geometry is working. Things like are the number of fibres right? There has been some confusion related to this.

The software group requires a paragraph on the checks that have been done and what reference (ie. mice note) stores the values the geometry has been checked against.


Station_layout.ppt (254 KB) Station_layout.ppt Lysenko, Oleg, 29 October 2011 05:14
Plane_order.ppt (91.5 KB) Plane_order.ppt Lysenko, Oleg, 29 October 2011 05:14

Updated by Santos, Edward almost 13 years ago

The number of fibres corresponds to the fiducial area in all stations. We must re-think if this is the right way to do the fiducial cut. The alternative is to make the full plane a SD and apply the cut later.


Updated by Tunnell, Christopher almost 13 years ago

I would have assumed fiducial volume cuts were done for MC at the same place in the dataflow that they were done for data. At least in SNO, we always did fiducial volume (or area in this case) cuts fairly late in the game.

So you're saying that we currently only have MC for our fiducial volume?


Updated by Rogers, Chris almost 13 years ago

Agree with Tunnell - we want to see what we lose from fiducial cut (helps to understand e.g. hit in tracker 1 but no hit in tracker 0, etc)


Updated by Santos, Edward almost 13 years ago

  • Assignee set to Santos, Edward

Updated by Tunnell, Christopher over 12 years ago

  • Assignee changed from Santos, Edward to Lysenko, Oleg

Edward: can you correct what you wrote about the fibres?

Oleg: Can you add what you figured out about the geometry?


Updated by Santos, Edward over 12 years ago

- The fibre parameters used to construct the SciFi sensitive detector are compared with the ones in MICE Note 135 (this is one of the unit tests).
- The number of fibres simulated depends on the area of the sensitive detector. We extended this to the full 32 cm diameter of each station. The fiducial cut, which brings this diameter down to 30 cm can be introduced later by the user in his analysis.
- The number of channels (212, 214 or 215, depending on the station/plane) is verified in another unit test for all 30 planes of the SciFi trackers.


Updated by Lysenko, Oleg over 12 years ago

Here are a few slides made by Geoff Barber. The first slide shows the view of the station onto the polished face of the connector. In the NIM paper, this view corresponds to the right direction on Fig. 19. The second slide shows the plane order as it was built. In the beam line, an observer is placed such that 'V' plane is the closest, and 'X' plane is the furthest to him. So in fact he can see the station layout in the mirroring to what is shown on slide 1. 'V' plane has +120 degrees rotation counterclockwise with respect the observer, 'W' plane has -120 degrees correspondingly, and 'X' plane is fixed without any rotation.
All this information is reflected in MiceModule files, and was translated in a DGML format for uploading in the configuration database.
In GDML, the related orientation of the components is achieved by nesting. For example, the following expression:

<Component name = "Tracker2Station2">
<Position x = “-0.6341” y = “0.037” z = "350.0" unit = "mm"/>
<Rotation x = “0.0” y = “0.0” z = “0.0” unit = "degree"/>
<Component name = "TrackerViewV">
<Position x = “0.0” y = “0.0” z = "-0.6398" unit = "mm"/>
<Rotation x = “0.0” y = “0.0” z = “120.0” unit = "degree"/>
<Component name = "TrackerViewW">
<Position x = “0.0” y = “0.0” z = "0.0125" unit = "mm"/>
<Rotation x = “0.0” y = “0.0” z = “-120.0” unit = "degree"/>
<Component name = "TrackerViewX">
<Position x = “0.0” y = “0.0” z = "0.6648" unit = "mm"/>
<Rotation x = “0.0” y = “0.0” z = “0.0” unit = "degree"/>

shows the relative spacing and orientation of the three planes 'V','W', and 'X' with respect to the Station2 in Tracker2. So whenever the tracker and/or its station is rotated, the internal spacing and orientation of planes within single station will not change. This is very convinient and allows to avoid changing of all internal parameters if the top component is moved/rotated.


Updated by Rogers, Chris over 11 years ago

  • Assignee changed from Lysenko, Oleg to Heidt, Christopher

Chris, this is the old issue for tracker geometry/CDB... I think you are looking into this right?


Updated by Heidt, Christopher over 11 years ago

Yeah I'll look into this.

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