Yajie Yuan
Co-I (Neutron Stars)
I am an assistant professor in the Department of Physics at Washington University in St. Louis. My research interests cover a wide range of high energy phenomena powered by black holes and neutron stars. One of the key questions I hope to answer is how the energy from the central engine eventually goes into high energy particles and radiation. This involves an interplay between general relativity, astroplasma physics, radiation mechanisms and sometimes quantum electrodynamics, in extreme regimes that are not accessible in terrestrial laboratories.
I use both theoretical analysis and state-of-the-art, large scale numerical simulations to model plasma dynamics and particle acceleration processes in these extreme environments. In the past, I have built first-principles models to explain the powerful γ-ray flares from the Crab pulsar wind nebula and from active galactic nuclei; I have carried out detailed studies of electron-positron pair production and γ-ray emission processes in black hole magnetospheres, which may explain the behavior of nearby supermassive black holes M87 and Sgr A∗ in the high energy band; recently I have been developing self-consistent scenarios for fast radio bursts powered by magnetars; I am also building models for the energy source behind the enigmatic, compact X-ray emitting corona in active galaxies and black hole X-ray binaries.
Currently we are in a particularly good position to unveil many of the mysteries of black holes and neutron stars: we have unprecedented multi-wavelength and multi-messenger coverage, which keeps bringing us new discoveries that reveal the extreme plasma environment around black holes and neutron stars; meanwhile, advance in numerical techniques allows ab-initio simulations of the underlying physical processes. I am excited to join our SCEECS colleagues on these endeavors.
Five recent relevant references
Yuan, Y., Beloborodov, A. M., Chen, A. Y., Levin, Y., Most, E. R., & Philippov, A. A. (2022). Magnetar Bursts Due to Alfvén Wave Nonlinear Breakout. The Astrophysical Journal, 933, 174. https://doi.org/10.3847/1538-4357/ac7529
Yuan, Y., Beloborodov, A. M., Chen, A. Y., & Levin, Y. (2020). Plasmoid Ejection by Alfvén Waves and the Fast Radio Bursts from SGR 1935+2154. The Astrophysical Journal Letters, 900, L21. https://doi.org/10.3847/2041-8213/abafa8
Chen, A. Y., & Yuan, Y. (2020). Physics of Pair Producing Gaps in Black Hole Magnetospheres. II. General Relativity. The Astrophysical Journal, 895, 121. https://doi.org/10.3847/1538-4357/ab8c46
Yuan, Y., Spitkovsky, A., Blandford, R. D., & Wilkins, D. R. (2019). Black hole magnetosphere with small-scale flux tubes—II. Stability and dynamics. Monthly Notices of the Royal Astronomical Society, 487(3), 4114. https://doi.org/10.1093/mnras/stz1599
Yuan, Y., Nalewajko, K., Zrake, J., East, W. E., & Blandford, R. D. (2016). Kinetic Study of Radiation-reaction-limited Particle Acceleration During the Relaxation of Unstable Force-free Equilibria. The Astrophysical Journal, 828, 92. https://doi.org/10.3847/0004-637X/828/2/92