The X-Ray Telescope (XRT) is a high resolution grazing incidence telescope, which is a succsessor to the highly successful Yohkoh. A primary purpose of the Solar-B is to observe the generation, transport, and emergence of solar magnetic fields, and ultimate dissipation of magnetic energy in a form such as flares and pico-flares, coronal heating, coronal mass ejection. The XRT aboard Solar-B observes the dissipation part of the life-cycle story of solar magnetic fields. High-resolution soft X-ray images would reveal magnetic field configuration and its evolution, allowing us to observe the energy buildup, storage and release process in the corona for any transient event. One of the unique features of XRT is its wide temperature coverage to see all the coronal features, that are not seen with any normal incidence telescope. Though we recognize the limitation of the filter-ratio method, we point out that coronal structures and events such as magnetic reconnection are sometimes more clearly seen in the temperature maps than in the X-ray maps (Yoshida & Tsuneta 1996, Kano & Tsuneta 1996)
The XRT consists of the X-ray and visible light optics, focal plane mechanisms (filters and shutter), and the 2k x 2k CCD camera. The Mission Data Processor (MDP) also plays a vital role for XRT.
The XRT was designed and developed by the Japan-US collaboration between Smithsonian Astrophysical Observatory (SAO), NASA MSFC, JAXA, and NAOJ. The XRT CCD camera was tested and calibrated in X-rays at the Advanced Technology Center of the NAOJ with JAXA.