Are supernova remnants PeVatrons ?

Our latest work is accepted for publication in ApJ. In this work, we have studied X-ray and gamma-ray properties of supernova remnants to evaluate their maximum attainable energies during lifetime. As most astrophysicists know, there are only a few supernova remnants which are accelerating particles up to PeV energies. We have evaluated this in aContinue reading “Are supernova remnants PeVatrons ?”

Chandra ACIS particle-induced background modeling tool

To model the particle-induced background spectrum for an arbitrary celestial observation with Chandra ACIS, we thoroughly analyzed all the available calibration data of the ACIS taken in 2002–2016 and have developed a tool to generate a model spectrum. We found CCD position-to-position and temporal variations of their energy spectra. The spatial variations were mostly seenContinue reading “Chandra ACIS particle-induced background modeling tool”

Quantitative Age Estimation of Supernova Remnants and Associated Pulsars

Our work on age estimation of supernova remnants has been accepted for publication in ApJ. The arXiv link is available. The motivation is that we still cannot be sure about the reliability of supernova remnants’ estimated ages, and thus want to quantify it. We have thoroughly collected available systems in which reliable age estimations wereContinue reading “Quantitative Age Estimation of Supernova Remnants and Associated Pulsars”

Moved to Konan University

Now I am at Konan University as a JSPS postdoc. Here I am working with Takaaki Tanaka. I plan to do observational studies of supernova remnants and detector development using X-ray CMOS sensors. Currently I am especially interested in cosmic rays, supernova remnants, in-orbit detector background of X-ray and gamma-ray satellites and X-ray detector development.Continue reading “Moved to Konan University”

Ph. D. Thesis

As my Ph. D. thesis, I have studied particle acceleration environment of supernova remnants (SNRs) through X-rays and gamma-rays. Maximum energies of accelerated particles and their dependence on environments were of particular interest. Investigating each SNR is not enough to study the evolution of the maximum energies. Thus I have used almost all the availableContinue reading “Ph. D. Thesis”

Finished Ph.D. program

I have finished my Ph.D. defense and graduated from The University of Tokyo. The dissertation title is “Systematic Study of Escape Processes of Cosmic Rays from Supernova Remnants based on Gamma-ray and Thermal X-ray Properties”. I have studied how accelerated particles diffuse from their acceleration sites, supernova remnants using X-ray and gamma-ray observational data. ToContinue reading “Finished Ph.D. program”