Solar Cycle Variation of Soft X-ray Irradiance Obtained by Hinode/XRT

The X-ray Telescope(XRT) on board the Hinode satellite(in operation since late 2006) has been taking soft X-ray images of the Sun with multiple broadband filters. Using the data from its synoptic full-Sun observing program, the full-Sun averaged filter-ratio temperature(Te) and emission measure(EM) are obtained, and from which mission-long solar X-ray irradiance is derived, in theory. However, in reality, the correcting the effect of instrumental failure or aging is crucially important to derive the reliable results over the whole mission period. In this presentation, we will show the mission-long variation of coronal Te, EM and irradiance (5-60A) based on the most recent method of correction: considering the effect of XRT pre-filter failure and taking the contamination layer developed on the X-ray analysis filters into account. The results will be compared with those from other instruments, like GOES/XRS, Yohkoh/SXT and MinXSS/X123.