Events Archive

Events Archive

Heliophysics Seminar, Dr. Vadim Roytershteyn
Tue, May 13, 2025, 2:00 pm3:00 pm

Title: Large-Amplitude, Short-Wavelength Fluctuations of Electric Field in the Transition Region of Collisionless Plasma Shocks

Dr. Vadim Roytershteyn, Space Science Institute, Boulder CO

Collisionless shocks are ubiquitous in space and astrophysical plasmas, where they often mediate conversion of flow energy into…

Heliophysics Seminar, Dr. Andrew Dimmock
Tue, Apr 29, 2025, 2:00 pm3:00 pm

Title: Exploring interplanetary shocks with Solar Orbiter

Dr. Andrew Dimmock, The Swedish Institute of Space Physics (IRF)

Shocks are ubiquitous throughout the universe: around stars, supernova remnants, active galactic nuclei, binary systems, comets, and planets, and are known to be efficient particle accelerators…

Heliophysics Seminar, Dr. Michael Hahn
Tue, Apr 15, 2025, 2:00 pm3:00 pm

Title: Velocity and Density Fluctuations in the Quiet Sun Corona

Dr. Michael Hahn, Columbia Astrophysics Laboratory, Columbia University

Some wave-driven models of coronal heating hypothesize that interactions between Alfvenic waves and density fluctuations enhance the rate of turbulent dissipation and thereby…

Heliophysics Seminar, Prof. Ellen Zweibel
Tue, Apr 1, 2025, 2:00 pm3:00 pm

Title: Collisionless Heating in Clusters of Galaxies

Prof. Ellen Zweibel, Departments of Physics & Astronomy, University of Wisconsin-Madison

Clusters of galaxies are pervaded by plasma which is hot, tenuous, magnetized, and host to a population of relativistic cosmic rays. The cooling time of this gas…

Heliophysics Seminar, Dr. Michael Terres
Tue, Mar 18, 2025, 2:00 pm3:00 pm

Title: Investigating Energy Exchange and Wave-Particle Interactions in the Solar Wind

Dr. Michael Terres, Center for Astrophysics | Harvard & Smithsonian 

Turbulence transfers energy from larger to smaller scales, wherein kinetic processes culminate in dissipation. In the context of the weakly collisional,…

Heliophysics Seminar, Mr. Hezekiah Grayer II
Tue, Mar 4, 2025, 2:00 pm3:00 pm

Title: On shock formation in collisionless plasma

Mr. Hezekiah Grayer II, Department of Mathematics (Program in Applied & Computational Mathematics), Princeton University

Collisionless shocks in space plasma are frequently observed in settings where the plasma is compressed against a magnetosphere (e.g., Earth’s…

Heliophysics Seminar, Dr. Alfred Mallet
Tue, Feb 18, 2025, 2:00 pm3:00 pm

Title: Suppression of Reconnection Onset by Flow Shear

Dr. Alfred Mallet, Space Sciences Laboratory, UC Berkeley

Reconnection is regularly observed at current sheets in the solar wind at 1AU, and the scalings of these current sheets suggest that they are dynamically formed by the turbulence itself. Theoretical…

Heliophysics Seminar, Dr. Riddhi Bandyopadhyay
Tue, Feb 4, 2025, 2:00 pm3:00 pm

Title: Chaotic Signal in Turbulent Space Plasmas

Dr. Riddhi Bandyopadhyay, Department of Astrophysical Sciences, Princeton University

Most space and astrophysical plasmas are considered to be in turbulent state, often characterized by stochastic fluctuations. Many laboratory experiments and numerical simulations…

Heliophysics Seminar, Dr. Imogen Gingell
Tue, Dec 17, 2024, 2:00 pm3:00 pm

Title: Magnetic Reconnection in the Transition Region of Collisionless Shockwaves

Dr. Imogen Gingell, School of Physics & Astronomy, University of Southampton

Observations by Magnetospheric Multiscale have demonstrated that magnetic reconnection occurs at Earth's bow shock, typically at thin current sheets…

Heliophysics Seminar, Dr. Valentin Skoutnev
Tue, Dec 3, 2024, 2:00 pm3:00 pm

Title: Tayler Instability Revisited

Dr. Valentin Skoutnev, Department of Physics, Columbia University

Tayler instability of toroidal magnetic fields is broadly invoked as the main trigger for turbulence and angular momentum transport in stellar radiative zones. I will discuss a recent systematic revision of the…