Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Prototype Schwarzschild-Couder Telescope for the Cherenkov Telescope
  Array: Commissioning the Optical System   A prototype Schwarzschild-Couder Telescope (pSCT) has been constructed at the
Fred Lawrence Whipple Observatory as a candidate for the medium-sized
telescopes of the Cherenkov Telescope Array Observatory (CTAO). CTAO is
currently entering early construction phase of the project and once completed
it will vastly improve very high energy gamma-ray detection component in
multi-wavelength and multi-messenger observations due to significantly improved
sensitivity, angular resolution and field of view comparing to the current
generation of the ground-based gamma-ray observatories H.E.S.S., MAGIC and
VERITAS. The pSCT uses a dual aspheric mirror design with a $9.7$ m primary
mirror and $5.4$ m secondary mirror, both of which are segmented. The
Schwarzschild-Couder (SC) optical system (OS) selected for the prototype
telescope achieves wide field of view of $8$ degrees and simultaneously reduces
the focal plane plate scale allowing an unprecedented compact ($0.78$m
diameter) implementation of the high-resolution camera ($6$mm/ $0.067$deg per
imaging pixel with $11,328$ pixels) based on the silicon photo-multipliers
(SiPMs). The OS of the telescope is designed to eliminate spherical and comatic
aberrations and minimize astigmatism to radically improve off-axis imaging and
consequently angular resolution across all the field of view with respect to
the conventional single-mirror telescopes. Fast and high imaging resolution OS
of the pSCT comes with the challenging submillimeter-precision custom alignment
system, which was successfully demonstrated with an on-axis point spread
function (PSF) of $2.9$ arcmin prior to the first-light detection of the Crab
Nebula in 2020. Ongoing and future commissioning activities are reported.

26
The categories of this paper are: bayes-an
22
The categories of this paper are: chao-dyn
23
The categories of this paper are: solv-int
28
The categories of this paper are: alg-geom
25
The categories of this paper are: patt-sol
18
The categories of this paper are: econ
35
The categories of this paper are: mtrl-th
14
The categories of this paper are: math-ph
5
The categories of this paper are: gr-qc
34
The categories of this paper are: chem-ph
4
The categories of this paper are: cond-mat
11
The categories of this paper are: hep-lat
27
The categories of this paper are: comp-gas
32
The categories of this paper are: atom-ph
37
The categories of this paper are: supr-con
2
The categories of this paper are: math