Search Publications
The 6.7 keV thermal emission lines in the stellar flare spectra of two chromospherically active Binaries: Algol and GT Mus
Eze, Ambrose Chukwudi; Esaenwi, Sudum; Madu, Fidelis Okey
Chromospherically active binaries' (CABs) are late-type evolved stars with strong chromosphere/coronae and high flare activity levels. Starspot evolution in these CABs and binaries reveals strong stellar and chromospheric activities. In binaries, the tidal interaction via the internal dynamo motion, during rapid rotation of the component stars gen…
A search for thermal X-ray emission from the composite supernova remnant G21.5-0.9 with Suzaku
Raycheva, Nergis C.; Sezer, Aytap
G21.5-0.9 is a young plerionic composite supernova remnant (SNR) hosting a bright pulsar wind nebula. The previous X-ray studies reported that the X-ray spectrum of the entire SNR can be fitted with a non-thermal spectral model, while the recent Chandra studies have pointed out that its X-ray spectrum also shows weak thermal emission. With this mo…
X-ray investigation of the X-ray source 1RXS J121902.7-630910 with Suzaku
Bakis, Hicran; Raycheva, Nergis C.; Sezer, Aytap +1 more
We present a study of the unidentified X-ray source 1RXS J121902.7-630910 based on Suzaku X-ray Imaging Spectrometer observation. We aim at clarifying the nature of the emission from 1RXS J121902.7-630910. We found that the spectrum is well represented by a thermal plasma model with an electron temperature of kTe ∼ 3.7 keV, the upper li…
Discovery of new X-ray sources near the unidentified gamma-ray source HESS J1841-055
Koyama, K.; Nobukawa, M.; Tsuru, T. G. +1 more
HESS J1841-055 is a diffuse unidentified gamma-ray source with the size of ∼1°.3 × 1°. No conclusive counterpart in other wavelengths has so far detected. To search for X-rays responsible for the TeV emission, the Suzaku observations were conducted, which covered a half region of the HESS source. In the soft band (0.5-2.0 keV), we discovered a dif…
Suzaku and Fermi observations of the supernova remnant G1.9 + 0.3
Gök, Fatma; Ergin, Tülün
We present results from the observation of the supernova remnant (SNR) G1.9 + 0.3, which is the youngest known SNR in the Milky Way, with the X-ray imaging spectrometer (XIS) on board Suzaku. We investigate the nature of the X-ray emission and compare our results with the previous X-ray studies. Additionally, we present the analysis results of the…
New insights into SNR evolution revealed by the discovery of recombining plasmas
Yamaguchi, Hiroya; Ozawa, Midori; Ohnishi, Takao
We report the discovery of recombining plasmas in three supernova remnants (SNRs) with the Suzaku X-ray astronomy satellite. During SNR's evolution, the expanding supernova ejecta and the ambient matter are compressed and heated by the reverse and forward shocks to form an X-ray emitting hot plasma. Since ionization proceeds slowly compared to sho…
Solar system planets observed with Suzaku
Miyoshi, Yoshizumi; Ezoe, Yuichiro; Ishikawa, Kumi +7 more
Recent results of solar system planets observed with the Japanese X-ray astronomy satellite Suzaku are reviewed. Thanks to the low instrumental background and good energy resolution, X-ray CCDs onboard Suzaku are one of the best probes to study diffuse X-ray emission. An overview of the Suzaku data of Jupiter and Earth is presented, along with pre…
X-ray emission from the Sagittarius D region
Koyama, Katsuji; Matsumoto, Hironori; Nobukawa, Masayoshi +2 more
We report results of the Suzaku observation toward the Sagittarius (Sgr) D region. Diffuse X-ray emission was clearly detected from inside the shell-type supernova remnant, the Sgr D SNR and is named G 1.02-0.18. A hint of an iron line is seen in the spectrum, suggesting that G 1.02-0.18 is a thin thermal plasma with the temperature of kT∼ 2keV . …
Possible Suzaku detection of non-thermal X-ray signals from a rotating magnetized white dwarf
Mukai, K.; Nakamura, R.; Enoto, T. +7 more
Although rotating neutron stars (NSs) have been regarded as being textbook examples of astrophysical particle acceleration sites for decades, details of the acceleration mechanism remain a mystery; for example, we cannot yet observationally distinguish “polar cap” models from “outer gap” models. To solve the model degeneracy, it is useful to study…
Oxygen line mapping of SN 1006 with Suzaku
Petre, Rob; Katsuda, Satoru; Tsujimoto, Masahiro +25 more
SN 1006 is one of the supernova remnants (SNRs) with relatively low-temperature electrons, considering the young age of just 1000 years. We carried out SN 1006 mapping observations with the X-ray Imaging Spectrometers (XIS) and the Hard X-ray Detector (HXD) onboard Suzaku, the fifth Japanese X-ray satellite. Thanks to the excellent spectral resolu…