Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: On the possiblity of using vertically pointing Central Laser Facilities
  to calibrate the Cherenkov Telescope Array   A Central Laser Facility is a system composed of a laser placed at a certain
distance from a light-detector array, emitting fast light pulses, typically in
the vertical direction, with the aim to calibrate that array. During
calibration runs, all detectors are pointed towards the same portion of the
laser beam at a given altitude. Central Laser Facilities are used for various
currently operating ultra-high-energy cosmic ray and imaging atmospheric
Cherenkov telescope arrays. In view of the future Cherenkov Telescope Array, a
similar device could provide a fast calibration of the whole installation at
different wavelengths. The relative precision (i.e. each individual telescope
with respect to the rest of the array is expected) to be better than 5%, while
an absolute calibration should reach a precisions of 4-11%, if certain design
requirements are met. Additionally, a preciser monitoring of the sensitivity of
each telescope can be made on time-scales of days to years.

35
The categories of this paper are: mtrl-th
19
The categories of this paper are: eess
12
The categories of this paper are: nucl-th
37
The categories of this paper are: supr-con
26
The categories of this paper are: bayes-an
10
The categories of this paper are: q-bio
31
The categories of this paper are: ao-sci
34
The categories of this paper are: chem-ph
27
The categories of this paper are: comp-gas
9
The categories of this paper are: nlin
18
The categories of this paper are: econ
21
The categories of this paper are: adap-org
32
The categories of this paper are: atom-ph
8
The categories of this paper are: hep-ex
14
The categories of this paper are: math-ph
22
The categories of this paper are: chao-dyn