Welcome!

I am Jing-Ze Ma (马竟泽), a theoretical and computational astrophysicist. I am currently a final-year PhD student at Max Planck Institute for Astrophysics, working with Selma de Mink and closely collaborating with Rüdiger Pakmor, Andrea Chiavassa, and Stephen Justham. I grew up in Beijing, China. Before moving to Germany, I obtained my bachelor’s degree at Tsinghua University in China in 2022.

I am interested in the 3D radiation magnetohydrodynamics of any multi-scale astrophysical object. I am the developer of the new radiation transport module in the 3D moving-mesh code AREPO.

Based on this technical advancement, I am currently leading the AREPO-Star project, targeting at multi-scale 3D radiation hydrodynamics of massive stars, binaries, and associated transients. The same technique can be used for other systems, e.g. black hole accretion, protoplanetary disks, star formation, etc.. For anyone interested, I am happy to discuss about possible applications of the code in your favorite astrophysical object.

I like to talk to other astrophysicists and get to know their works. I also enjoy hiking and singing with the choir.

What’s new?

Try this interactive 3D rendering below! Rotate the 3D star with your mouse or fingers, and zoom in-and-out to explore its multi-scale aspherical circumstellar material and rainy convection!

(Cyan: Iso-density surface of the circumstellar material. Orange: Temperature field. Blue: Warm upflow. Red: Cold dense downdraft. Based on the 10 Msun 3D red supergiant stars simulated with AREPO)

Fast rendering: https://jingzema.com/AREPO-RSG/arepo_rsg_csm_fast.html

Video download: https://drive.google.com/drive/folders/1DhW4L3ryYtekgJM2MGuWkzXvS3hBu-xK?usp=share_link

Arxiv paper: Using 3D simulation, we found that the red supergiants develop strong global pulsations hundreds of years before they die, which eject dense material into the stellar surroundings. This provides a new view of the origin of the circumstellar material seen in interacting supernovae. We predict the progenitor pulsations and highly-confined circumstellar material should be present in most hydrogen-rich supernovae, which can be tested with Vera Rubin Observatory and incoming ultra-violet satellites such as ULTRASAT and UVEX.

Using 3D simulation, we also found that the text-book view of convection we see in boiling water is not what is happening near the surface of giant stars. Instead, the surface convection is driven by cold rains of material rapidly cooled. Those rains merge into larger streams as they penetrate deeper inside the star. We predict that this rainy convection inside the star leaves its imprint in the stellar atmosphere, and can be seen in the most advanced telescopes such as ALMA.

(Orange: Temperature field. Blue: Warm upflow. Red: Cold dense downdraft. Based on the 10 Msun 3D red supergiant stars simulated with AREPO)

Higher resolution: https://jingzema.com/AREPO-RSG/arepo_rsg.html

Faster rendering: https://jingzema.com/AREPO-RSG/arepo_rsg_fast.html

Video download: https://drive.google.com/drive/folders/1DhW4L3ryYtekgJM2MGuWkzXvS3hBu-xK?usp=share_link