Atomic mass measurements provide fundamental information about the nature of the nucleus due to the mass lost to binding energy in nucleosynthesis. At the Low Energy Beam and Ion Trapping (LEBIT) facility at the Facility for Rare Isotopes Beams, mass measurements of nuclei across the nuclear chart are performed to improve our understanding of the formation of the elements, explosive astrophysical events, the structure of the nucleus, and even fundamental symmetries of the universe.Type-I x-ray bursts are particularly complex and exciting sites of nucleosynthesis. A neutron star in a binary system slowly consumes its companion, building up a proton rich crust so hot and dense that it spontaneously undergoes rapid nuclear fusion across its entire surface, generating massive amounts of energy over the course of a few minutes, and emitting powerful bursts of x-rays detectable on earth. Then they do it again every few hours. These events are the site of the rapid proton capture (rp) process. In this work, a high-precision mass measurement of phosphorus-27, an isotope with a 260 ms lifetime-less than the blink of an eye-is discussed. Its impact on the path of the rp process and therefore the energyproduced in x-ray burst is investigated using a complex supercomputer simulation. Based on the results, the importance in astrophysics of having precision measurements over theoretical predictions and high performance simulations over simple approximations is discussed.With the transition from the National Superconducting Cyclotron Laboratory (NSCL) to the Facility for Rare Isotope Beams (FRIB), a plethora of rare isotopes previously beyond the reach of nuclear physicists due to low production rates and short half-lives have become available. To measure the masses of these exotic isotopes, new tools have been implemented at LEBIT. The Phase Imaging Ion Cyclotron Resonance (PI-ICR) Technique is one of these tools, and it has vastly improving experimental sensitivity. As with any technique requiring parts-per-billions level precision, it is full of complications in hardware, software, and understanding of systematic uncertainties. These challenges and how they have been overcomewill be discussed. Finally, preliminary results of PI-ICR proof of effectiveness will be shown: successful PI-ICR mass measurements of two rare isotopes produced by FRIB, the previously known 105Sn and the world's first mass measurement of 22Al.
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