Search for sterile neutrinos at reactors

Understand

The sensitivity to the sterile neutrino mixing at very short baseline reactor neutrino experiments is investigated.

• In the case of conventional (thermal neutron) reactors it is found that the sensitivity is lost for $\Delta m^2 \gtrsim$ 1 eV$^2$ due to smearing of the reactor core size.
• On the other hand, in the case of an experimental fast neutron reactor Joyo, because of its small size, sensitivity to $\sin^22\theta_{14}$ can be as good as 0.03 for $\Delta m^2 \sim$ several eV$^2$ with the Bugey-like detector setup.