Recent News


The first Program Advisory Committee (PAC) meeting for FRIB concluded on August 13, 2021. Eighty-two experiment proposals had been submitted to PAC1 of FRIB for evaluation of their scientific merit and feasibility. The MoNA Collaboration, working together with other researchers outside the collaboration, submitted three proposals, two of which were approved for beam time by the PAC! This is a very good outcome for the collaboration, since the proposal selection is highly competitive.


The two approved proposals are:

21016 C. Hoffman First observation of neutron-unbound 30F
21066 T. Baumann Neutron-Unbound Excited States in 53,55Ca
(approved with limited beam time to investigate 53Ca)


These two experiments will push the invariant mass measurements of the collaboration to heavier systems. While the measurement of 30F will determine the ground-state characteristics of this unbound nucleus, the investigation of the neutron-rich 53Ca focuses on neutron-unbound excited states, which will help to pin down theoretical calculations that possibly can shed light onto the location of the neutron drip line for calcium. Only about 30% of the requested beam time could be approved, due to the high demand for FRIB.


By the numbers, the PAC-recommended experiments following peer review represent (compared to the request):

  • 34 (out of 82 requested) experiments
  • 3,108 hours (out of 9,784 hours) beam-on-target hours
  • 4,122 facility-use hours
  • 401 (out of 597) individuals
  • 25 (out of 30) countries represented
  • 24 U.S. states
  • 88 institutions
  • 15 out of 17 National Academies benchmarks for FRIB


Summer project fun!

Paul Gueye's summer student, Maya Wallach, created a fun and interesting way to display information about our research. Just click on a nucleus in the chart of the nuclides to get information about the nature of the nucleus and any of our experiments with it. Or you can play the chart like a piano. It's great fun and a novel way to display nuclear physics research.

Try it here, Musical MoNA

E19013 - Last MoNA Experiment of the CCF era, completed!

With a Herculian effort by all the NSCL/FRIB members of the collaboration, a complex triple coincidence experiment to explore reactions leading to 12Be in the final state. The neutron-unbound nucleus 13Be is known to decay to 12Be + n with a relativley low resonance energy but previous experiments had left it unclear whether the ground state of 12Be or its 0+ isomer was populated in the final state. This leads to a significant ambiguity in constructing the level-scheme. To resolve this ambiguity, we performed a triple coincidence (fragment, neutron, and microsecond-delayed gamma-rays). This experiment was run in September of 2020 during the COVID pandemic. A small group of faculty, staff, post-doctorial researchers, and graduate students setup, ran the experiment, and packed away the devices. This invloved moving several miles of cables, a few tons of detectors, and synchronizing three distinct data acquisition system. Many thanks from the rest of the collaboration!

MoNA in S2
Detector telescope

Figure 1: Experimental setup showing CAESAR (CsI) surrounding the charged partcile telescope which detects delayed gamma-rays from stopped 12Be nuclei, and MoNA which detects the prompt neutrons from the in-flight decay of 13Be into 12Be + n.
Figure 2: Experimental setup showing CAESAR (CsI) surrounding the charged partcile telescope which detects and stops 12Be nuclei from the in-flight decay of 13Be. This telescope was designed, developed, and tested by Prof. Nathan Frank of Augustana College with MRI funding from the NSF (Grant 1827840).