Jens Mahlmann
astrophysics-plasmaphysics-theory-models
About me
I specialize in high-energy astrophysics, focusing on plasma processes in magnetized environments such as magnetars, black holes, stars, and accretion flows. My work integrates theoretical frameworks with advanced simulations conducted on high-performance computing systems. Specifically, my primary research investigates the origins of plasma near neutron stars and the mechanisms behind the generation of radio and X-ray bursts during magnetospheric instabilities. Guided by the detailed observations and advanced theories of planetary magnetospheres, including those of Earth and Jupiter, I explore fundamental plasma processes in extreme astrophysical environments. I build trustworthy non-linear models of how electromagnetic energy within stellar magnetospheres transforms into signals observable through telescopes. With expertise in scientific code development, I customize simulations to capture the intricacies of diverse astrophysical environments ensuring the highest accuracy in modeling complex plasma dynamics. Beyond my research, I am deeply committed to fostering effective communication and conflict resolution within scientific teams. I actively incorporate these communication skills into my work environment, contributing to a collaborative and inclusive scientific community.
Magnetar Activity
Magnetars are young, highly magnetized neutron stars with decades of observational data. However, we must still explain their rich phenomenology from first principles: fast radio bursts (e.g., SGR 1935+2154), the keV peak of the persistent X-ray emission with hardening at higher energies (e.g., 1E 2259+586), and radio emission following some of their outbursts (e.g., XTE J1810−197). A significant part of magnetar bursting activity is likely driven by magnetospheric processes within or around the magnetar light cylinder. Our work answers a fundamental question of high-energy astrophysics: How do magnetars emit (coherent) radiation?
Leveraging fundamental plasma processes is a crucial tool for our work on magnetospheric dynamics. They allow insights into many exciting astrophysical phenomena. Our recent work includes magnetized Kelvin-Helmholtz modes in interacting neutron star magnetospheres, radiation drag in photon-rich shocks around cosmic explosions, and kink-unstable magnetic columns in magnetized coronae. We are passionate about conserving and further developing fundamental plasma physics intuition as an essential tool for accurately modeling magnetospheric dynamics throughout the universe.
Fundamental AstroPlasma
Computational Innovation
We develop and use highly accurate plasma simulations to identify regions of magnetic energy dissipation in compact object magnetospheres. Modern computational infrastructures are the backbone of our work. In our projects, we use high-order finite-volume methods to model magnetized environments with force-free electrodynamics and magnetohydrodynamics. Particle-in-cell (PIC) codes are powerhouses for understanding complex plasma processes on the kinetic scale. We contribute to the development of the new GPU-accelerated PIC code entity. Pushing the limits of resolved scales and the analysis of large datasets requires constant innovation. We promote this passionately.
The Journey
I will join the Department of Physics and Astronomy (Dartmouth College) as an Assistant Professor in the Winter term of 2025. I am currently a postdoc with Andrei Beloborodov and Lorenzo Sironi at Columbia University. I was previously a postdoc co-supervised by Anatoly Spitkovsky at Princeton University and Alexander Philippov at the Center for Computational Astrophysics (Flatiron Institute). I received a PhD in Physics from the University of Valencia (Spain) under the supervision of Miguel Angel Aloy Toras, and Pablo Cerdá-Durán, and a B.Sc. and M.Sc. in Physis from the University of Hannover (Germany).
Our lab at Dartmouth College has upcoming openings for graduate students and postdoc scholars! We are excited to welcome PhD students who are passionate about modeling magnetized plasmas to answer pressing questions in high-energy astrophysics. You can find information about becoming our student at the Department of Physics and Astronomy of Dartmouth College!
If you’re interested in joining the lab, please email us a description of your research interests, program goals and a CV with contact information for references to start a conversation.
Our lab believes in fostering an inclusive space where we can chase our research curiosities and passions. To ensure symbiotic mentor-mentee relationships, we hope your interests resonate with one or more of the following: plasma astrophysics, compact object magnetospheres, high-energy radiative feedback, numerical method development, big data analysis, and innovative tools for next generation plasma modeling.
Jens Mahlmann 