Hiroko
Shinnaga
Ph.D. in Science
Conduct Milky Way Galaxy Inspired Researches
新永 浩子
鹿児島大学 学術研究院理工学域理学系 物理・宇宙プログラム
〒890-0065 鹿児島市郡元 1-21-35
Department of Physics and Astronomy, Kagoshima University
1-21-35 Korimoto, Kagoshima 890-0065 JAPAN
Research Projects
We explore the mysteries of the Universe, focusing on star formation and evolution, the interstellar medium, and the roles of the magnetic field in our Milkyway Galaxy to understand how the magnetic field shapes our Galaxy, mainly using world-class radio telescopes.
1. Magnetic Fields in Star Forming Regions
Stars are born in dense molecular clouds, and magnetic fields play a crucial role in their evolution. Using astronomical polarimetry, we visualize the “invisible” magnetic field lines.
Figure 1: Visualization of magnetic field structure in a massive star-forming region.
*Figure 1: Visualization of magnetic field structure in a low-mass star-forming dense core. (Fukaya, Shinnaga et al. 2023) *
- Key Finding: Our observations revealed that magnetic fields are surprisingly well-ordered even in turbulent environments.
- Telescopes Used: ALMA, JCMT (SCUBA-2/POL-2).
2. Magnetic Fields in Evolved Stars and their Circumstellar Medium – High-Resolution Observations with ALMA, VLA, VERA
The Atacama Large Millimeter/submillimeter Array (ALMA), the Very Large Array (VLA), and the VLBI Exploration of Radio Astrometry (VERA) allows us to zoom in on the very heart of stars that are just before supernova explosions.
Figure 2: An image of a dying massive (25 Msun) star, VYCMa, with prominent mass loss activities traced using various molecular Maser lines. (Shinnaga, Oyadomari, Imai et al. 2025)
3. Roles of Magnetic Field in mass accretion onto the Super Massive Black Hole (Sgr A*) at the heart of our Milkyway Galaxy
Using JCMT SCUBA-2/POL-2 submillimeter polarization technique, we measured the 3D magnetic field strengths of the Circumnuclear Disk (CND) of surrounding Sgr A* by comparing with a self-similar accregion disk model.
Figure 3: Left: Magnetic field strengths measured in 3D in the Circumnuclear Disk (CND) based on a self-similar accretion disk model. Right: Measured polarization vectors towards the CND of our Milkyway Galaxy's SMBH Sgr A* (Sato, Shinnaga, Furuya et al. 2025)