  We present the results of our Moon impact flashes detection campaigns
performed around the maximum activity period of the Perseid meteor shower in
2012 and 2013. Just one flash produced by a Perseid meteoroid was detected in
2012 because of very unfavourable geometric conditions, but 12 of these were
confirmed in 2013. The visual magnitude of the flashes ranged between 6.6 and
9.3. A luminous efficiency of 1.8 $\times$ 10$^{-3}$ has been estimated for
meteoroids from this stream. According to this value, impactor masses would
range between 1.9 and 190 g. In addition, we propose a criterion to establish,
from a statistical point of view, the likely origin of impact flashes recorded
on the lunar surface.
