3 papers
astro-ph.HE2026
Diffusive or Ballistic? Distributions and Spectra of PeV Cosmic Rays around Microquasars
Yutaka Fujita, Rohta Takahashi, Norita Kawanaka
In the standard Galactic cosmic-ray (CR) paradigm, protons are accelerated up to ~1 PeV by Galactic sources. While supernova remnants (SNRs) have been traditionally considered as t…
astro-ph.HE2025
Hadronic origin of the very high-energy gamma-ray emission from the low-luminosity AGN in NGC 4278
Asahi Shoji, Yutaka Fujita, Norita Kawanaka +2
The Large High Altitude Air Shower Observatory has detected very high-energy (VHE) gamma rays from NGC 4278, which is known to host a low-luminosity active galactic nucleus (AGN).…
astro-ph.GA2025
Re-examination of the CO absorption line in the M87 nucleus
Norita Kawanaka, Hiroshi Nagai, Yutaka Fujita
We analyzed the archival ALMA data of the nuclear region of M87 and evaluate the molecular gas content from the CO(2--1) absorption line. We found an enigmatic variability in the a…