Hello. I am an associate professor at Osaka University, interested in understanding the nature of black holes. As an astronomer, I have been working on both theoretical and observational astrophysics.
Our paper on the Zeeman effect in MAD is accepted by PASJ.
Title: On the Zeeman Effect in Magnetically-Arrested Disks.
Authors: Yoshiyuki Inoue
Magnetically arrested disk (MAD) has been argued as the key accretion phase to realize the formation of relativistic jets. However, due to the lack of magnetic field measurements of accreting systems, MAD has not been observationally confirmed yet. Here we propose that a strong magnetic field accompanied by MAD would induce the Zeeman splitting of relativistically broadened Fe Kα fluorescence lines in X-ray binaries and active galactic nuclei, where we consider a two-phase medium in the inner accretion disk, magnetically dominated hot corona and cold reflector.
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Bachelor Thesis Presentation Day
We are pleasure to hear that two excellent undergraduate students in our group defended their bachelor thesis presentations. Katsunori Kusakabe looked into the stellar magnetic field condition to realize the magnetically arrested disk in X-ray binaries. Tatsuki Fujiwara worked on 26Al gamma-ray line signals from solar bodies as well as the estimation of past cosmic-ray activity using comets. Congratulations to all of them!
Our paper on the MeV source contribution to the inner Galactic Diffuse emission is accepted by ApJ.
Title: MeV Gamma-Ray Source Contribution to the Inner Galactic Diffuse Emission .
Authors: Naomi Tsuji, Yoshiyuki Inoue, Hiroki Yoneda, Reshmi Mukherjee, Hirokazu Odaka
The origin of the inner Galactic emission, measured by COMPTEL with a flux of ∼10−2 MeV cm−2 s−1 sr−1 in the 1-30 MeV energy range from the inner Galactic region, has remained unsettled since its discovery. In this paper, we elaborate on a model of individual MeV gamma-ray sources unresolved by COMPTEL.
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Dr. Ellis R. Owen joined our group.
Our paper on ALMA detection of pc-scale blobs at the head of kpc-scale jet in NGC 1068 by ApJL.
Title: ALMA Detection of Parsec-scale Blobs at the Head of a Kiloparsec-scale Jet in the Nearby Seyfert Galaxy NGC 1068.
Authors: Tomonari Michiyama, Yoshiyuki Inoue, Akihiro Doi, Dmitry Khangulyan We present Atacama Large Millimeter/submillimeter Array observations at ≈100 GHz with 0.05 arcsec (3 pc) resolution of the kiloparsec-scale jet seen in the nearby Seyfert galaxy NGC 1068, and we report the presence of parsec-scale blobs at the head of the jet.
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Our paper on the contribution of radio galaxies to the cosmic gamma-ray background radiation is accepted by ApJ.
Title: High energy emission component, population, and contribution to the extragalactic gamma-ray background of gamma-ray emitting radio galaxies.
Authors: Yasushi Fukazawa, Hiroto Matake, Taishu Kayanoki, Yoshiyuki Inoue, Justin Finke
In this study, we systematically studied the X-ray to GeV gamma-ray spectra of 61 {\it Fermi} Large Area Telescope (LAT) detected radio galaxies. We found an anticorrelation between peak frequency and peak luminosity in the high-energy spectral component of radio galaxies, similar to blazars.
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Our Group Member, Naomi Tsuji, is now an assistant professor at Kanagawa University .
Bachelor Thesis Presentation Day
We are pleasure to hear that our excellent undergraduate student defended his bachelor thesis presentation. Tomoya Yamada worked on radio emission signals from AGN disk winds. Congratulations!
Our paper on interstellar gas heating by PBHs is accepted by JCAP.
Title: Interstellar Gas Heating by Primordial Black Holes.
Authors: Volodymyr Takhistov, Philip Lu, Graciela B. Gelmini, Kohei Hayashi, Yoshiyuki Inoue, Alexander Kusenko