Kohei Ichikawa (PhD Candidate, Department of Astronomy, Kyoto University)

In your view, what makes this meeting unique?

Ichikawa: I think EAYAM is unique in being supported by the East Asian Core Observatories Association (EACOA). The goal of EACOA is to promote dialogue and collaborations between the four big astronomical observatories in the East Asian region: NAOJ, ASIAA, the Korea Astronomy and Space Science Institute (KASI), and the National Astronomical Observatories of China (NAOC). The meeting really encourages graduate students and postdocs to interact informally and to spark new collaborations.

What does your role as a member of the Scientific Organizing Committee involve?

Ichikawa: I have three main roles. One is to discuss the scientific goals of EAYAM 2015 with other Scientific Organizing Committee members in the four regions to maximize international ties and future collaborations in East Asia. This time, the focus is on sharing knowledge about professional development and career paths for researchers, so we tried to include two panel discussions about topics such as work-life balance, challenges faced by postdocs, and outreach activities. The second is the reviewing process. We selected invited speakers, reviewing all of the abstracts submitted for the meeting and finalized about 60 presentations. I reviewed in the field of galaxies and black holes. The third involves organizing funds for travel and accommodation for participants from each country. This is essential in order to lower the barrier for participants -- especially for graduate students who don't have their own grants -- to attend EAYAM.

Could you please talk us through your area of specialization?

Ichikawa: I'm tackling the issue of how supermassive black holes arise. There are tremendous numbers of galaxies in the universe, and now astronomers believe there is at least one supermassive black hole in the center of each galaxy. Even in our galaxy, in the galactic center, astronomers now know that there is one supermassive black hole with a mass about 106 times that of the Sun! But nobody knows how such supermassive black holes were formed. I've been studying active galactic nuclei (AGN), where supermassive black holes are in a rapidly evolving stage due to great mass accretion from the surrounding area. They are very bright due to the release of gravitational potential by the accretion onto the supermassive black holes. Therefore, we can observe very distant AGN from the Earth, meaning that younger supermassive black holes can be investigated through AGN.

What kind of telescopes do you use to observe AGN?

Ichikawa: Basically AGN are very bright in all wavelengths, but two wavelength bands are especially important in understanding the growth of supermassive black holes. One is X-ray, as X-ray emission originates from the accretion disk and around the hot electron coronal region, meaning that X-ray traces the inherent AGN power. Japan's X-ray satellite Suzaku is a suitable telescope to observe such X-ray emission. The other important emission is infrared, as infrared emission originates from surrounding dusts heated by the central engine. By observing in the infrared band, we can estimate how much of the dusts, or "fuel" of AGN, are located around the central engine, and we can calculate how much of the dusts can accrete to the central engine (and finally to the supermassive black holes) in the future. Japan's Subaru telescope in Hawaii is a suitable telescope to observe those infrared bands. I generally use those telescopes as well as combining other observational data, for example, from Japan's infrared satellite AKARI, and NASA's X-ray satellite Swift.

What would be the best way to view your publications?

Ichikawa: All of our work is archived under the "astro-ph" category on arxiv.org, an open access database with e-prints in astronomy, physics, mathematics, computer science, quantitative biology, quantitative finance and statistics. It was started by Cornell University. There are mirror sites located all over the world. There's one located in Kyoto University at the Yukawa Institute for Theoretical Research. My publication list is also available from my website.

That sounds fascinating. In addition, I understand you are involved in public engagement projects such as Kyoto Science Sequence (KSS). Could you tell us a little more about this project?

Ichikawa: Yes. Although outreach activities have become more and more widespread in recent years, my colleagues and I realized that very rarely do these events cover cutting-edge research for high-school students who already have a great interest in science. So, we launched KSS in 2013 specifically to connect graduate students or postdocs with high school students. In addition to making communication materials aimed at high-school level, we also arrange to give talks at high schools. This is mutually beneficial because graduate students or postdocs can gain experience giving one-hour presentations and hone their communication skills, while high school students can gain insights into new research fields and think about future career paths. I was a founding member and have served as president of the KSS project since 2014.

And finally, what would be your advice to early-career researchers interested in continuing their astronomical studies at Kyoto University?

Ichikawa: Keep active! It's important to attend as many seminars in your department as possible, even if they don't necessarily relate to your main research interests, and don't hesitate to ask questions. If you come up against any hurdles, reach out and ask -- somebody may have experienced the same things. Make lots of friends by attending conferences and meetings. They will be your potential collaborators. And finally, read papers that helped to define the fundamental principles in your field. This knowledge will be indispensable in your future research and collaborations.

Kohei Ichikawa is a PhD candidate at the Department of Astronomy, Kyoto University. He obtained his bachelor's and master's degrees in astronomy from Kyoto University in 2010 and 2012 respectively. He received a JSPS Research Fellowship for Young Scientists in 2012 and is a member of the Astronomical Society of Japan. Since 2014, he has served as president of Kyoto Science Sequence, a science communication group organized by graduates of Kyoto University.