Kristopher Yirak

Kristopher Yirak is studying heterogeneity in stellar jets, the effect of jets on self-gravitationally-bound systems, the single- and multi-mode Rayleigh-Taylor instability, and other laboratory astrophysics. Kris got his BS in physics & BS in astronomy from the University of Washington in 2004. While at the UW he was involved with the Undergraduate Radio Astronomy Group, which he headed in his senior year. In 2004 he was awarded the Higgs/Osborne Prize for having shown "exceptional ability in laboratory courses." His participation in observations at the ​Manastash Ride Observatory in the summer of 2003 provided data for an ApJ ​publication. Kris worked for two years on the ​ZaP Flow Z-Pinch Project, PI'ed by Uri Shumlak in the Dept. of Aeronautics & Astronautics at the UW.

Kris is a recipient of the Frank J. Horton Fellowship at the University of Rochester. He has been a participant in two of the ​JETSET conferences, in ​January 2007 in Sauze d'Oulx, Italy and ​January 2008 in Galway, Ireland. His work consists primarily of modelling energetic outflows from young stellar objects (YSOs), the progenitors of stars. Employing the flexibility and robustness afforded to him by the AstroBEAR AMR code, he has been able to explore dynamic parameter regimes previously uninvestigated. In particular, his work suggests a reinterpretation of outflows not as smoothly varying beams of material but instead as collimated, episodic, clustered outbursts.

Kris, with assistance from Brandon Shroyer, is working to implement the ​HYPRE suite of solvers in AstroBEAR. Such implementation will allow AstroBEAR users to take advantage of AMR while employing important physics such as self-gravity, explicit resistive diffusivity, and (at some point) radiation transport.

Kris currently has two publications in ApJ, with several more in preparation. Kris anticipates defending in the Spring of 2010.