  Emission line at the energy ~3.55 keV detected in different galaxies and
galaxy clusters has caused a lot of discussion in high-energy astrophysics and
particle physics communities. To reveal the origin of the line, we analyzed
publicly available observations of MOS cameras from XMM-Newton cosmic
observatory - the instrument with the largest sensitivity for narrow faint
X-ray lines - previously combined in X-ray sky maps. Because of extremely large
timescale needed for detailed analysis, we used the wavelet method instead.
Extensive simulations of the central part of Andromeda galaxy are used to check
the validity of this method. The resulting list of wavelet detections now
contains 235 sky regions. This list will be used in future works for more
detailed spectral analysis.
