Thermal-vacuum test of XRISM spacecraft

I have been attending the thermal-vacuum test of the XRISM spacecraft held at the JAXA Tsukuba Space Center, Japan in this August. This is the final chance for us (Xtend team) to check the performance of Xtend, which includes the basic operation, energy resolution, CCD temperature control, etc. The picture is from the XRISM officialContinue reading “Thermal-vacuum test of XRISM spacecraft”

Chandra X-ray study of the RCW 86 southwestern region

Our recent paper entitled “Particle acceleration controlled by ambient density in the southwestern rim of RCW 86” has been accepted for publication in ApJ (arXiv link). The southwestern region of the supernova remnant RCW 86 is very suitable for studying how acceleration conditions are affected by environmental properties. We have found that the acceleration efficiencyContinue reading “Chandra X-ray study of the RCW 86 southwestern region”

Presentation at EAS 2022

I will give a presentation at the European Astronomical Society Annual Meeting 2022. The presentation is about our recent X-ray study of RCW 86 (ApJ, under review). We investigated the shock velocity, thermal & non-thermal X-ray properties of the southwestern region of RCW 86. Our findings suggest that ambient density controls the particle acceleration conditions:Continue reading “Presentation at EAS 2022”

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”