International Awards for Yuto Bekki
With the help of computer simulations, the MPS researcher described the properties of the long-period oscillations of the Sun.
Dr. Yuto Bekki of the Max Planck Institute for Solar System Research (MPS), Germany received awards from two international associations of professional astronomers. He received the Patricia Edwin PhD Thesis Prize from the Solar Physics Division of the European Physical Society (EPS) and an honorable mention from the Sun and Heliosphere Division of the International Astronomical Union (IAU). Using a suite of computer simulations, which he developed from scratch, the young researcher characterized a class of long period oscillations which were recently discovered by the MPS helioseismology group. His results, in combination with ever improving observations, provide a new way of probing the Sun’s interior.
These oscillations were observed a few years ago on the solar surface as gigantic swirling motions. They have characteristic sizes in the order of hundreds of thousands of kilometers and have periods in the order of a month. These long-period oscillations owe their existence to the Sun’s rotation, which has a period of about 27 days. The oscillations can be broken down into a number of modes, each of which corresponds to a single tone of a musical instrument. Each mode is characterized by its oscillation period and its flow velocity pattern - which is observable at the solar surface. “The numerical models developed by Dr. Yuto Bekki played an essential role in the unambiguous identification of many of the Sun’s inertial modes,” explains his PhD adviser, Prof. Laurent Gizon.
By changing the parameters of the simulation, Dr. Yuto Bekki also investigated what the observable properties of the modes can teach us about the interior of the Sun. "The long-period oscillations open exciting new possibilities," explains Dr. Yuto Bekki. "These oscillations contain information about the deep convection zone of the Sun," he says. This layer of the Sun extends up to 200000 kilometers below the surface and contains motions associated with the hotter material ascending to the surface and the cooler material sinking back down. Understanding these motions is particularly important because they drive large-scale motions in the solar interior.
Dr. Yuto Bekki studied at the University of Tokyo, where he specialized on topics of solar physics for his bachelor's and master's theses. His master's thesis was awarded the Academic Achievement Award from the University of Tokyo. During the period from May 2018 to March 2022, he pursued his PhD studies at the International Max Planck Research School on Solar System Science at the University of Göttingen under the supervision of Dr. Robert Cameron and Prof. Laurent Gizon. Currently, Dr. Yuto Bekki is continuing his research at the MPS in the Solar and Stellar Interiors Department within the framework of the ERC Synergy Grant WHOLE SUN.
The EPS is a consortium consisting of the physical societies of 42 European countries. Each year, the Solar Physics Division of the EPS awards the Patricia Edwin PhD Thesis Prize for a particularly outstanding doctoral thesis. The award ceremony will take place at next year’s meeting of the Solar Physics Division of the EPS in Torino, Italy.
The IAU is the worldwide association of professional astronomers. Each year, the divisions of the IAU give honorable mentions to PhD theses from the previous year.