主持人：刘四明教授

时间：2022年12月3日（周六）19：00

ZOOM：95150896241

入会密码：289633

题目：Magnetohydrodynamic Turbulence and Cosmic Ray Transport

主讲人：Huirong Yan professor/ Leading Scientist

2015 - present W3 chair professor at Institut für Physik und Astronomie, Universität 

Potsdam; and Leading Scientist at DESY Zeuthen

2009 – 2015 Research Professor, Kavli Institute for Astronomy & Astrophysics, 

Peking University

2008 - 2010 Theoretical Astrophysics Program Prize Fellow, U Arizona

2005- 2008 Postdoctoral Fellow, Canadian Institute of Theoretical 

Astrophysics (CITA), Toronto

2005.8 PHD Dept. of Astronomy/ University of Wisconsin-Madison/ Unites States of 

America

2002.6 M.Sc. Dept. of Astronomy/ University of Wisconsin-Madison/ Unites States of 

America

1998 .7 B.Sc. Astrophysics at Peking University/ China

Current research interests

Turbulence and Plasma Astrophysics

Space physics

Cosmic Ray and High Energy Astrophysics

Interstellar medium

Plasma instabilities and their Astrophysical Implications

Atomic alignment and Astrophysical Magnetic Fields

Physics of Interstellar and Circumstellar Dust

Awards

2019.8-9 Visiting scholarship, KITP program “Multiscale Phenomena in Plasma 

Astrophysics”,USA

2013 Helmholtz Distinguished Professorship

2013 - 2014 Labex scholarship, France

2012 - 2015 Winner of Templeton senior grant from Beyond the Horizons program: Grants

 for Research on Big Questions in Astronomy, Astrophysics and Cosmology sponsored by

 Templeton foundation (US) and Chinese Academy of Science

2012 Visiting Professorship, International Institute of Physics, Brazil (3 months)

2012.1 Visiting Professorship, GCOE Program, Nagoya University, Japan

Abstract

Cosmic ray propagation is determined by the properties of interstellar turbulence. The multiphase nature of ISM and diversity of driving mechanisms give rise to spatial variation of turbulence properties. A new chapter of CR propagation research has begun when studies of particle transport and interstellar turbulence can confront each other. I shall report our current understandings of MHD turbulence and particle transport. In particular, the proportion of magnetosonic modes is revealed to increase with increasing compressive forcing from turbulence simulations, which entails an extra spatial dependence of cosmic rays transport.Both theoretical and observational studies will be presented. With the advanced technique we developed, it is found that Alfven and magnetosonic modes are distinguishable from observations. Clear signatures of critically balanced turbulence as well as the compressible modes are revealed from space/astro plasma in conjunction with the behavior of particle transport. Different regimes of particle transport, e.g., diffusion vs. superdiffusion, isotropicvs. anisotropic diffusion, will be discussed in relation to turbulence properties.