Otto Haxel Award for Yuto Bekki

In his doctoral thesis, the young researcher developed computer models to investigate long-period solar oscillations.

Dr. Yuto Bekki of the Max Planck Institute for Solar System Research (MPS) has been honored with the Otto Haxel Award for Physics for his doctoral dissertation. In collaboration with the German Physical Society (DPG), the Society for the Promotion of the Karlsruhe Institute of Technology (KIT) annually bestows this award upon the three best dissertations in physics from the Universities of Göttingen, Heidelberg, and KIT. During his doctorate, Yuto Bekki studied the Sun’s long-period oscillations, which had only recently been discovered by researchers at the MPS. The computer simulations developed by Yuto Bekki have made a significant contribution to identifying and characterizing these long-period solar oscillations. The award was presented at a ceremony held at KIT.

Processes and phenomena within the Sun’s interior significantly influence the nature of our star and are particularly fundamental to its magnetic activity. However, since this region is inaccessible to direct observation, researchers have long utilized helioseismology methods to gain insights into the Sun’s internal dynamics. To do this, they study solar oscillations, which propagate through the star’s interior and manifest themselves at its surface.

In this endeavor, in addition to the Sun’s “high notes”, acoustic waves with periods of around five minutes, researchers are pinning their hopes on its “low notes”: solar oscillations with periods around 27 days. The existence of such non-acoustic oscillations was predicted more than 40 years ago, but had not been identified until recently. In 2021, scientists from the MPS department “Solar and Stellar Interiors” headed by Prof. Dr. Laurent Gizon succeeded in detecting them in observational data from NASA’s Solar Dynamics Observatory (SDO), which has been continuously observing the Sun since 2010, thus providing the extensive series of observations necessary for this discovery.

As part of his doctoral thesis, Dr Yuto Bekki developed computer simulations to identify and characterize the different modes or “notes” of the long-period solar oscillations. These modes differ in their specific oscillation periods and the patterns of their flow velocity on the solar surface. Such information is crucial for developing these Sun’s “low notes” into a valuable and powerful tool for helioseismology in the coming years.

For his dissertation, the KIT Freundeskreis und Fördergesellschaft e.V., the Society for the Promotion of the Karlsruhe Institute of Technology, in cooperation with the DPG has now honored Yuto Bekki with the Otto Haxel Award of the third rank. The award commemorates Prof. Dr. Otto Haxel, who headed KIT as Managing Director from 1970 to 1975. Prior to this, the physicist held professorships at the Universities of Göttingen and Heidelberg.

Dr. Yuto Bekki studied physics at the University of Tokyo. He completed his doctoral thesis, which was supervised by Prof. Dr. Laurent Gizon and Dr. Robert Cameron, at the MPS and at the University of Göttingen as part of the International Max Planck Research School on Solar System Science. The young scientist has received numerous prizes and honors, including the Patricia Edwin PhD Thesis Prize from the Solar Physics Division of the European Physical Society, an honorable mention from the International Astronomical Union, and the Otto Hahn Medal from the Max Planck Society.