About

My friends call me Piper, Annie, Josie, or Pipes but Joanna or any nicknames you can come up with will work!

I am currently a Postdoc at Lawrence Livermore National Lab where I started in September of 2025. I work on nuclear criticality safety validation experiments and prepare benchmarks for submission to the ICSBEP. This validates neutronics codes and they nuclear data they use. I also continue to develop numerical methods for solving the radiation transport equation on CPUs and GPUs.

I graduated from Oregon State University where I got my PhD in mechanical engineering with an option in thermal fluid sciences and a minor in nuclear engineering. I defended on June 9th of 2025. My research through grad school and continuing on is in time-dependent Monte Carlo neutron transport for high performance/heterogeneous compute systems enabled by Python. This research was part of the Center for Exascale Monte Carlo Neutron Transport (CEMeNT) which was funded by the NNSA, through which I got to run transport problems on some of the largest supercomputers in the world at that time! I also worked on developing transient deterministic neutron transport algorithms for GPU computations.

The common thread in my work is how to solve radiation transport problems (mainly neutrons but also occasionally photons) on modern HPC architectures full of interesting heterogeneous structures and occasionally bespoke hardware accelerators. My work sits somewhere between numerical methods, neutral particle transport phenomena, sustainable scientific software development, and exaclass (really big) high performance computing research.

While in grad school I have worked at Advanced Micro Devices (AMD) in Data Center GPU solutions, and Los Alamos National Lab (XCP-3 & CCS-2) adding functionality to production radiation transport codes. Before that in undergrad I interned at Argonne and Thomas Jefferson National Labs where I worked on superconducting and conventional particle accelerator magnet design and optimization.

In my free time I hang out with my friends, play the tenor sax (not that well), refurbish furniture I find on the street, and make a pretty good pun every now and again. I have an adorable 40 pound dog: Rutabaga (Rudy) (Shar-Pie, Super Mutt mix) and my roommate’s dog Pamela (German Shorthair Pointer) pictured below. Rudy actually did a DNA test to figure out some of this stuff. You can see his results here.

Rudy was adopted from Heartland Humane Society and I could not recommend them more if you’re looking for a fury friend in the mid Willamette valley area.

Academic Lineage

My full academic lineage can be found thru my advisor’s (Kyle Niemeyer) Mathematics Genealogy Project profile. It’s kinda fun to go snooping around and see who you can find! (There’s)