Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: The monochromator beamline at FLASH: performance, capabilities and
  upgrade plans   The monochromator beamline at the FLASH facility at DESY is the worldwide
first XUV monochromator beamline operational on a free electron laser
(FEL)source. Being a single-user machine, FLASH demands a high flexibility of
the instrumentation to fulfil the needs of diverse experiments performed by a
multidisciplinary user community. Thus, the beamline has not only been used for
high-resolution spectroscopy that it was originally designed for, but also for
pump-probe experiments controlling the temporal-spectral properties at moderate
resolution, and as a filter for high harmonics of the FEL at very low
resolution. The present performance and capabilities of the beamline are
discussed with emphasis on particularities arising from the nature of the FEL
source, and current developments are presented aiming to enhance its
capabilities for accommodating a wide variety of experiments.

10
The categories of this paper are: q-bio
13
The categories of this paper are: quant-ph
1
The categories of this paper are: cs
18
The categories of this paper are: econ
8
The categories of this paper are: hep-ex
24
The categories of this paper are: dg-ga
7
The categories of this paper are: hep-th
37
The categories of this paper are: supr-con
30
The categories of this paper are: q-alg
19
The categories of this paper are: eess
27
The categories of this paper are: comp-gas
12
The categories of this paper are: nucl-th
9
The categories of this paper are: nlin
0
The categories of this paper are: hep-ph
4
The categories of this paper are: cond-mat
20
The categories of this paper are: acc-phys