Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Pointing Calibration for the Cherenkov Telescope Array Medium Size
  Telescope Prototype   Pointing calibration is an offline correction applied in order to obtain the
true pointing direction of a telescope. The Cherenkov Telescope Array (CTA)
aims to have the precision to determine the position of point-like as well as
slightly extended sources, with the goal of systematic errors less than 7 arc
seconds in space angle. This poster describes the pointing calibration concept
being developed for the CTA Medium Size Telescope (MST) prototype at
Berlin-Adlershof, showing test results and preliminary measurements. The MST
pointing calibration method uses two CCD cameras, mounted on the telescope
dish, to determine the true pointing of the telescope. The "Lid CCD" is aligned
to the optical axis of the telescope, calibrated with LEDs on the dummy
gamma-camera lid; the "Sky CCD" is pre-aligned to the Lid CCD and the
transformation between the Sky and Lid CCD camera fields of view is precisely
modelled with images from special pointing runs which are also used to
determine the pointing model. During source tracking, the CCD cameras record
images which are analysed offline using software tools including Astrometry.net
to determine the true pointing coordinates.

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The categories of this paper are: dg-ga
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The categories of this paper are: physics
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The categories of this paper are: q-fin
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The categories of this paper are: q-bio
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The categories of this paper are: hep-th
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The categories of this paper are: cmp-lg
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The categories of this paper are: hep-ph
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The categories of this paper are: cond-mat
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The categories of this paper are: hep-ex
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The categories of this paper are: q-alg
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The categories of this paper are: chao-dyn
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The categories of this paper are: nucl-ex
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The categories of this paper are: bayes-an
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The categories of this paper are: gr-qc
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The categories of this paper are: math-ph
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The categories of this paper are: patt-sol