Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: The ALFA Laser and Analysis Tools   The optimal performance of adaptive optics systems can only be maintained if
the wavefront reference is bright and compact. Experience has shown that both
of these important criteria are remarkably difficult to achieve with laser
guide stars, and this contribution gives an account of the methods by which
ALFA attempts to reach them. First, the production of a high quality, high
power laser beam is described. However, this quality is unavoidably compromised
along the path to the launch telescope. In order to rectify this, a new set of
diagnostic tools which monitor the quality of the out-going beam has been
installed, and these are also described. Lastly, we outline a number of
possible modifications on which we are working. If successful, these may allow
a substantial improvement in the beam quality.

11
The categories of this paper are: hep-lat
19
The categories of this paper are: eess
29
The categories of this paper are: funct-an
35
The categories of this paper are: mtrl-th
26
The categories of this paper are: bayes-an
28
The categories of this paper are: alg-geom
2
The categories of this paper are: math
1
The categories of this paper are: cs
31
The categories of this paper are: ao-sci
18
The categories of this paper are: econ
8
The categories of this paper are: hep-ex
21
The categories of this paper are: adap-org
32
The categories of this paper are: atom-ph
24
The categories of this paper are: dg-ga
37
The categories of this paper are: supr-con
0
The categories of this paper are: hep-ph