Wave Heating of the Solar Corona by Dr. Michael Hahn скачать в хорошем качестве

Wave Heating of the Solar Corona by Dr. Michael Hahn

This lecture was recorded on February 13th, 2026. About February's Featured Lecture: The solar corona is the outer layer of the Sun, which is visible from Earth during solar eclipses. At one million degrees, the temperature of the corona is much greater than that of the underlying photosphere, which is only about 6000 K. Understanding the heating of the corona has been a longstanding problem in astrophysics for over 80 years and we still do not have a complete answer. One theory for coronal heating invokes plasma waves, especially Alfven waves which form ripples in the magnetic field. Alfven waves are generated by convection in lower layers of the Sun and carry energy into the corona where the waves are dissipated converting the energy they carry into particle heating. Observations support the view that Alfven waves can carry and dissipate sufficient energy to heat much of the corona. In fact, the Alfven waves appear to dissipate more rapidly than was originally expected. In order to understand this rapid dissipation, we are conducting laboratory experiments in order to study the physics these waves under controlled conditions similar to the corona. Although our experiments are designed to understand the Sun, the same plasma physics plays an important role in plasmas on Earth, such as in fusion devices. In this way, insights from studying the Sun are improving both our understanding of astrophysics and our ability to model and control artificial plasmas. About Dr. Michael Hahn: Dr. Hahn has been interested in astronomy since he was young, and he was an amateur astronomer as a hobby when he was in school. He went to Carnegie Mellon to study Physics, graduating in 2005. During that time, he did a summer research internship at Montana State University, on the topic of solar physics. He thought the Sun was interesting, but at the time he worried it was too narrow a topic to focus on. Reasoning that the Sun is a big ball of plasma, he decided to study plasma physics and obtained a PhD in that topic from the Applied Physics department at Columbia. Next, he moved two buildings over and joined the Columbia Astrophysics Laboratory, originally to work on topics related to atomic physics and spectroscopy. Since then, he has been able to combine all of his interests in spectroscopy, solar physics, and laboratory plasmas. *We apologize for the poor audio balance during some of the video segments*