The Neutron Emission Ratio Observer NERO at the National Superconducting Cyclotron Laboratory

The new neutron counter NERO (Neutron Emission Ratio Observer) was built at the National Superconducting Cyclotron Laboratory (NSCL) for measuring $P_{\rm n}$ values of neutron-rich nuclei produced as fast fragmentation beams. The design was motivated by the requirement of being coupled to the NSCL beta counting system, so that $\beta$-decay particles and neutrons emitted from implanted nuclei can be measured simultaneously, while keeping a high efficiency. The detector's performance and main features will be discussed, as well as recent measurements done at NSCL for astrophysical studies of the r-process.