X光雙星是研究中子星、恆星級黑洞與近密雙星吸積機制的重要天體，許多X光雙星的性質可藉由研究它們的光變現象獲得，它們的光變時間尺度範圍可小到一毫秒以下而大到數千日，不同的時間尺度光變展現X光雙星不同部分的特性。中子星內部結構探測器(NICER)已在2017年中投入觀測，它將會開啟一個X光時序研究的新時代。我們提出利用NICER及其它X光望遠鏡的觀測資料針對X光雙星的光變現象進行研究，包括準週期震盪、超軌道光變與中子星表面的低穩定核反應(稱為毫赫茲準週期震盪)等非穩定週期性現象利用希爾伯特-黃轉換進行分析，以及利用X光光變與脈衝星時序研究X光雙星軌道與其緻密天體參數變化。此外，我們將加入國際大型綜合巡天望遠鏡(LSST)計畫，利用此計畫之空前巡天之能力與天文台地理優勢，將針對吸積雙星在可見光與近紅外波段之長期光變現象進行持續監視，配合X 光波段的監測資料，對X光雙星長期光變之成因做一深入探討。 ;X-ray binaries are important astrophysical objects to study the properties of neutron star and stellar size black hole, as well as the accretion mechanism for the close binary systems. Many properties of the X-ray binaries can be revealed by investigating their variability, whose time scale can be as short as less than 1 ms up to more than thousand days. Studying the variability of X-ray binaries allows us to understand different parts of X-ray binaries. A new generation of facility for X-ray timing, Neutron star Interior Composition Explorer (NICER), has been devoted into observation since mid of 2017. It is expected to open a new era for X-ray timing investigations. We propose using the data from NICER and other X-ray telescopes to study the variability of X-ray binaries, including the unstable periodic variations that can be resolved by Hilbert-Huang transform, such as quasi-periodic oscillations (QPOs), superorbital modulation and oscillations form marginally stable nuclear burning on neutron star surfaces (called millihertz QPOs) and orbital and compact object parameter variations by flux modulations or pulsar timing. Furthermore, we also propose to participate an international project, Large Synoptic Survey Telescope (LSST). Utilizing the unprecedented sky survey ability and the advantage of the location of the site, it is able to process the constantly monitoring the long-term variability of X-ray binaries in optical-infrared band. Combined with the monitoring light curves from X-ray band telescopes, we are able to further understand the natures of long-term modulations of the X-ray binaries.
