Magnetic reconnections in laser-produced plasmas have been investigated in order to gain a better understanding of microscopic electron dynamics, which is relevant to space and astrophysical phenomena. Researchers from Osaka University, in collaboration with researchers from the National Institute for Fusion Science and other universities, have reported direct measurements of pure electron outflows relevant to magnetic reconnection using a high-power laser, Gekko XII, at Osaka University’s Institute of Laser Engineering. Their findings have been published in the journal Scientific Reports.
Magnetic reconnection is a key process in many space and astrophysical phenomena, including solar flares and magnetic substorms, in which magnetic energy is released as plasma energy. It is well understood that electron dynamics play critical roles in the magnetic reconnection triggering mechanism. However, observing the tiny electron scale phenomena in the vast universe has been extremely difficult.
As a result, the researchers were able to create situation-only electrons that were directly coupled with magnetic fields in laser-produced plasmas. Laboratory astrophysics provides access to the miniature universe.
“The key players in space plasmas can sometimes be found on a small scale. Even with cutting-edge numerical simulations, it is extremely difficult to see their actions in large-scale space phenomena “ToseoMoritaka, the study’s author, explains. “Laser experiments can now set up a new stage to illuminate their actions. The findings will connect various observations and simulations at the macroscopic and microscopic levels.”
For the first time, the pure electron outflow associated with electron-scale magnetic reconnection has been measured in laser-produced plasmas using collective Thomson scattering measurements.
“The findings of this study are applicable not only to space and astrophysical plasmas, but also to magnetic propulsion of spacecrafts and fusion plasmas,” explains study lead author Yasuhiro Kuramitsu.
“Macroscopic phenomena such as magnetic reconnections and collisionless shocks are governed by microscopic electron dynamics. This is a unique and universal property of plasma that is not found in other gases or liquids. This can now be addressed in laboratories through direct local measurements of the plasma and magnetic field. We will model long-standing open problems in the universe in laboratories. Knowing the nature of plasmas may lead to the discovery of, say, fusion plasma.”