Low Temperature Plasma for Astrochemistry: Toward a Further Understanding with Continuous and Precise Temperature Control*

Astrochemistry is concerned with understanding the chemical evolution in the universe. Despite the harsh and unfavorable conditions, active organic syntheses occur throughout the universe. Laboratory experiments that simulate the conditions of the target astrophysical environment have been used to study the nature and abundances of molecules. In such laboratory simulations, discharge plasma can be used to simulate the energetic processes that occur in the universe. We review the use of discharge plasma in the domain of astrochemistry by considering Titan as an example. Additionally, we discuss the necessity for a plasma source whose temperature can be well controlled at ranges below room temperature (300 K) to simulate the low temperatures that are representative of astrophysical environments. Finally, we present a recent advancement achieved by our group in using cryoplasma, whose temperature can be controlled in a continuous and precise manner below room temperature, to simulate the chemical processes that occur on the surfaces of icy bodies in the outer solar system. © 2020 The Japan Society of Plasma Science and Nuclear Fusion Research