Approaching the mystery of the Fermi bubble, the Galactic center

Researchers from Waseda University, the University of Tokyo, RIKEN and Kanazawa University found evidence that the Fermi bubbles erupting from the Galactic center and the giant loop structures observed from X-ray monitoring are both traces of a massive explosion which occurred 10 million years ago.

When the bubbles expand, it is thought that the surrounding high-temperature gas was compressed and heated to form a giant loop structure. The research team conducted a systematic observation and analysis centered on the Japanese X-ray astronomical satellite, Suzaku, for five years since 2013. It became clear how the now-calm galaxy actively repeated explosions 10 million years ago and went through extreme evolution.

Their research was published in The Astrophysical Journal on July 25, 2018.

Reference

• Diffuse X-Ray Emission from the Northern Arc of Loop I Observed with Suzaku
• Masahiro Akita, Jun Kataoka, Makoto Arimoto, Yoshiaki Sofue, Tomonori Totani, Yoshiyuki Inoue, and Shinya Nakashima
• Published in The Astrophysical Journal on July 25, 2018