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• compact.xml: defines the geometry in terms of detector modules, each of which corresponds to classes in GeomConverter - used by GeomConverter and LCSim
• detector.properties: other (non-geometry) detector parameters
• SamplingFractions: sampling fractions for each calorimeter
• LCDD file for the geometry: generated from the compact.xml - used by SLIC

Current "official" geometries

Conventions followed for all geometries unless noted otherwise:

• Beam spot on target defines (0, 0, 0); Y is vertical, Z points down the magnet bore

HPS-Proposal2014-v3 (three versions with different B-fields)

Official geometry for 2014 run studies.

• SVT rotated 30.52 mrad around target; single sensors for layers 1-3, double sensors with double readout (unganged) for layers 4-6
• ECal flange is tesselated solid: face at z=1318 mm and photon hole aligned at 30.52 mrad from target
• Front face of ECal crystals is z=1393 mm; ECal aligned so the photon beam intersects centerline of ECal at its front face

HPS-TestRun-v3

Official geometry for 2012 test run as-built.

• Current best guess at alignment of SVT
• Plate-and-pipe ECal flange
• ECal as surveyed

Adding a new detector

• make a subdirectory of hps-detectors/detectors; name of the subdirectory is the name of the detector
• add name of the detector to detectors/taglist.txt
• copy from another detector: compact.xml, detector.properties, SamplingFractions
• in compact.xml: change name and comment in <info> block
• in detector.properties: change name, change ConditionsReader if necessary (TestRunConditionsReader for 2012 test run, HpsConditionsReader for 2014 run) - both of these lines are required
• use GeomConverter to make LCDD file: see below

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