Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Frequency response of an atomic resonance driven by weak
  free-electron-laser fluctuating pulses   Motivated by recent experiments pertaining to the interaction of weak
SASE-FEL pulses with atoms and molecules, we investigate the conditions under
which such interactions can be described in the framework of a simple
phase-diffusion model with decorrelated atom-field dynamics. The nature of the
fluctuations that are inevitably present in SASE-FEL pulses is shown to play a
pivotal role in the success of the decorrelation. Our analysis is performed in
connection with specific recent experimental results from FLASH in the soft
X-ray regime.

12
The categories of this paper are: nucl-th
20
The categories of this paper are: acc-phys
4
The categories of this paper are: cond-mat
18
The categories of this paper are: econ
19
The categories of this paper are: eess
25
The categories of this paper are: patt-sol
29
The categories of this paper are: funct-an
9
The categories of this paper are: nlin
31
The categories of this paper are: ao-sci
15
The categories of this paper are: nucl-ex
16
The categories of this paper are: stat
27
The categories of this paper are: comp-gas
33
The categories of this paper are: plasm-ph
2
The categories of this paper are: math
0
The categories of this paper are: hep-ph
34
The categories of this paper are: chem-ph