Implantation detectors for first decay studies with FDSi

With the recent opening of the Facility for Rare Isotope Beams (FRIB) at Michigan State University, commissioning experiments have been underway for the FRIB Decay Station Initiator (FDSi) [1]. Implantation detectors serve as a vital part of the experimental setup, as they can stop the high-energy radioactive beam and then measure its subsequent decays. For FDSi, multiple position-sensitive detectors have been developed for implantation in both the discrete array and within the Modular Total Absorption Spectrometer (MTAS) [2]. The discrete array of FDSi uses a segmented inorganic scintillator coupled to a multi-anode photomultiplier tube, providing good timing resolution for neutron time of flight measurements [3]. To fit within MTAS, a brand-new smaller detector has been developed with a scintillator coupled to an array of silicon photomultipliers for millimeter position resolution at both implant and decay energies. The high position resolution allows for better correlation between beta decays and ion implantation events, and a reduction of background in measurements.

[1] https://fds.ornl.gov/initiator/

[2] M. Karny et al., NIM A 836, 83-90 (2016)

[3] R. Yokoyama et al., NIM A 937, 93-97 (2019)