  In a paper appearing in this issue of Physics Letters A, Ericsson et al.
raise some critical comments on the experiment [F. Cardone, R. Mignani, A.
Petrucci, Phys. Lett. A 373 (2009) 1956] we carried out by cavitating a
solution of thorium-228, which evidenced its anomalous decay behaviour, thus
confirming the results previously obtained by Urutskoev et al. by explosion of
titanium foils in solutions. In this Letter, we reply to these comments. In our
opinion, the main shortcomings of the criticism by the Swedish authors are due
to their omitting of inserting our experiment in the wider research stream of
piezonuclear reactions, and to the statistical analysis they used, which does
not comply with the rules generally accepted for samples with small numbers.
However, apart from any possible theoretical speculation, there is the basic
fact that two different experiments (ours and that by Urutskoev et al.),
carried out independently and by different means, highlight an analogous
anomaly in the decay of thorium subjected to pressure waves. Such a convergence
of results shows that it is worth to further carry on experimental
investigations, in order to get either a confirmation or a disproof of the
induced-pressure anomalous behaviour of radioactive nuclides even different
from thorium.
