We have observed the prompt emission of GRB100418A, from its beginning by the MAXI/SSC (0.7-7 keV) on board the International Space Station followed by the Swift/XRT (0.3-10 keV) observation. The light curve can be fitted by a combination of a power
law component and an exponential component (decay constant is $31.6pm 1.6$ sec). The X-ray spectrum is well expressed by the Band function with $E_{rm p}leq$8.3 keV. This is the brightest GRB showing a very low value of $E_{rm p}$. It satisfies the Yonetoku-relation ($E_{rm p}$-$L_{rm p}$). It is also consistent with the Amati relation ($E_{rm p}$-$E_{rm iso}$) in 2.5$sigma$ level.
We present here the observation of the Cygnus Superbubble (CSB) using the Solid-state slit camera (SSC) aboard the Monitor of All-sky X-ray Image. The CSB is a large diffuse structure in the Cygnus region with enhanced soft X-ray emission. By utilizi
ng the CCD spectral resolution of the SSC, we detect Fe, Ne, Mg emission lines from the CSB for the first time. The best fit model implies thin hot plasma of kT ~ 0.3 keV with depleted abundance of 0.26 +/- 0.1 solar. Joint spectrum fitting of the ROSAT PSPC data and MAXI/SSC data enables us to measure precise values of NH and temperature inside the CSB. The results show that all of the regions in the CSB have similar NH and temperature, indicating that the CSB is single unity. The energy budgets calculation suggests that 2-3 Myrs of stellar wind from the Cyg OB2 is enough to power up the CSB, whereas due to its off center position, the origin of the CSB is most likely a Hypernova.
Solid-state Slit Camera (SSC) is an X-ray camera onboard the MAXI mission of the International Space Station. Two sets of SSC sensors view X-ray sky using charge-coupled devices (CCDs) in 0.5--12,keV band. The total area for the X-ray detection is ab
out 200,cm$rm ^2$ which is the largest among the missions of X-ray astronomy. The energy resolution at the CCD temperature of $-$70 degc is 145,eV in full width at the half maximum (FWHM) at 5.9,keV, and the field of view is 1deg .5 (FWHM) $times$ 90deg for each sensor. The SSC could make a whole-sky image with the energy resolution good enough to resolve line emissions, and monitor the whole-sky at the energy band of $<$ 2,keV for the first time in these decades.
