What would you like to introduce to readers in this series?

“Seeing the Universe with X-rays.” This is my research, but for many people it is difficult to visualize. The shining celestial objects in the night sky emit light of wavelengths other than just visible light; they also emit x-rays for example. But, waht are x-rays? What is x-ray spectroscopy? What do you learn from them?

In this series, I would like to familiarize you with the curious topics of x-ray observations and x-ray spectroscopy. On Earth when x-rays are used in hospitals or the security check at an airport, they show the &ldqu;shadow” of an object which the x-rays hit. In contrast, in astronomical observations instead of using an artificial x-ray source, the x-rays are emitted by the celestial objects themselves.

This article introduces a “Galaxy Cluster”, a typical astronomical object where the visible light and x-ray images are totally different. When observed by visible light, there seems to be nothing in the space, but from x-ray observation we know that actually it is filled with high-temperature gas. Our view of galaxy clusters has been changed by x-ray observations. This has implications for the astrophysics of phenomena such as galaxy cluster formation. I am happy when everyone understands this excitement.

My research field and current interests:

I research the structure formation of galaxies and galaxy clusters. focusing on high-temperature gas which radiates x-ray. I should say that right now my galaxy research and galaxy cluster research are separate. In the future, I want to do more unified research. In the near future, the ASTRO-H satellite introduced in this article will allow us to determine the gas velocity which has been unknown until now. I think that the picture of galaxies and galaxy clusters will be changed by the determination of hitherto unmeasured physical quantities.

Data

Name

Yoh Takei

Affiliation

JAXA

Job Title

Assistant Professor

Field of Expertise

X-ray Astrophysics