Status of the Multi-layer Active target for MoNA Experiment (MAME)

The MoNA Collaboration uses the invariant mass technique to study neutron-unbound systems at the Facility for Rare Isotope Beams (FRIB). The Collaboration developed a silicon-beryllium based active segmented target to increase the production yield and resolution of the reconstructed decay energy since the corresponding cross section for such systems is of order of 0.1-1.0 mb. This target was used successfully for two experiments (²⁶O lifetime and ³¹Ne excited states). However, the 140 mm thick silicon detectors have limitations from current saturation and radiation damage, typical for these solid-state devices, thus preventing to benefit fully from the high FRIB beam rates (which is about 4 orders of magnitude more than previous experiments). Investigation of a gas-filled time projection chamber coupled to a gaseous electron multiplier (GEM) is under development to address this issue. This Multi-layer Active Target for MoNA Experiment (MAME) is expected to enable missing mass capability by tracking recoils and fragments from reactions used to produce neutron-unbound systems. Additionally, the scalable readout system (SRS) data acquisition system is used for the high channel density readout. The calibration of the SRS system is now underway, giving preliminary data that will aid in the design of the system. The reaction mechanisms for isotope production are also being studied with a GEANT4 simulation. The status of this project will be reviewed and discussed.