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	An underlying clock in the extreme flip-flop state transitions of the black hole transient Swift J1658.2-4242 期刊论文 OAI收割 Astronomy and Astrophysics, 2020, 卷号: 641, 页码: A101 作者: HXMT \| 收藏 \| 浏览/下载：65/0 \| 提交时间：2022/02/08 accretion accretion disks black hole physics X-rays: binaries time Astrophysics - High Energy Astrophysical Phenomena Abstract: Aims: Flip-flops are top-hat-like X-ray flux variations, which have been observed in some transient accreting black hole binary systems, and feature simultaneous changes in the spectral hardness and the power density spectrum (PDS). They occur at a crucial time in the evolution of these systems, when the accretion disc emission starts to dominate over coronal emission. Flip-flops remain a poorly understood phenomenon, so we aim to thoroughly investigate them in a system featuring several such transitions. Methods: Within the multitude of observations of Swift J1658.2-4242 during its outburst in early 2018, we detected 15 flip-flops, enabling a detailed analysis of their individual properties and the differences between them. We present observations by XMM-Newton, NuSTAR, Astrosat, Swift, Insight-HXMT, INTEGRAL, and ATCA. We analysed their light curves, searched for periodicities, computed their PDSs, and fitted their X-ray spectra, to investigate the source behaviour during flip-flop transitions and how the interval featuring flip-flops differs from the rest of the outburst. Results: The flip-flops of Swift J1658.2-4242 are of an extreme variety, exhibiting flux differences of up to 77% within 100 s, which is much larger than what has been seen previously. We observed radical changes in the PDS simultaneous with the sharp flux variations, featuring transitions between the quasi-periodic oscillation types C and A, which have never been observed before. Changes in the PDS are delayed, but more rapid than changes in the light curve. Flip-flops occur in two intervals within the outburst, separated by about two weeks in which these phenomena were not seen. Transitions between the two flip-flop states occurred at random integer multiples of a fundamental period of 2.761 ks in the first interval and 2.61 ks in the second. Spectral analysis reveals the high and low flux flip-flop states to be very similar, but distinct from intervals lacking flip-flops. A change of the inner temperature of the accretion disc is responsible for most of the flux difference in the flip-flops. We also highlight the importance of correcting for the influence of the dust scattering halo on the X-ray spectra.
	Optimal Gimbal System Control Strategy for Error Prediction Compensation 会议论文 OAI收割 Shanghai, China, 2019-08-14 作者: Yang, Yongqing; Hao, Wei; Yu, Tianye; Xie, Meilin; Liang, Yanbing \| 收藏 \| 浏览/下载：32/0 \| 提交时间：2020/05/18 prediction error compensation energy spectrum analysis optimal control tracking gimbal system periodic error
	Fabrication and Spectral Analysis of Ho3+, Yb3+ Co-doped (LaLu)2O3 Powders 期刊论文 OAI收割 Faguang Xuebao/Chinese Journal of Luminescence, 2018, 卷号: 39, 期号: 3, 页码: 301-306 作者: Li, Jian; Dai, Yu-Hang; Zhu, Zhong-Li; Zhang, Ying \| 收藏 \| 浏览/下载：19/0 \| 提交时间：2019/09/17 Powders Energy transfer Lanthanum compounds Light Lutetium compounds Particle size Spectrum analysis
	Controllable Synthesis and Surface-enhanced Upconversion Luminescence of Ultra-thin Gold Shell Coated NaYF4: Yb, Er@SiO2 Nanostructures 期刊论文 OAI收割 Faguang Xuebao/Chinese Journal of Luminescence, 2018, 卷号: 39, 期号: 11, 页码: 1505-1512 作者: An, Xi-Tao; Wang, Yue; Mu, Jia-Jia; Li, Jing; Zhang, Li-Gong \| 收藏 \| 浏览/下载：33/0 \| 提交时间：2019/09/17 Gold coatings Curve fitting Energy transfer Finite difference time domain method Fluorescence Forster resonance energy transfer Laser excitation Nanoshells Nanostructured materials Shells (structures) Silica Spectrum analysis Surface plasmons
	Microstructure characteristics and forming environment of late Quaternary Period loess in the Loess Plateau of China 期刊论文 iSwitch采集 ENVIRONMENTAL EARTH SCIENCES, 2010, 卷号: 59, 期号: 8, 页码: 1807-1817 作者: Deng, Jin; Wang, Lanmin; Zhang, Zhenzhong; Bing, Hui 收藏 \| 浏览/下载：80/0 \| 提交时间：2019/10/08 Loess Plateau Loess microstructures Climatic change Sand dropping Energy spectrum analysis
	Spectroscopy and Energy Transfer in Yb3+ and Tm3+ Co-doped Gd3Ga5O12 Crystal 期刊论文 OAI收割 Chinese Journal of Structural Chemistry, 2010, 卷号: 29, 期号: 3, 页码: 449-458 G. T. Chen, H. Zhou, W. C. Lv, Y. Wang, Z. Y. You, J. F. Li, Z. J. Zhu and C. Tu 收藏 \| 浏览/下载：33/0 \| 提交时间：2012/11/02 Yb3+/Tm3+ co-doped Gd3Ga5O12 crystal Judd-Ofelt (J-O) theory spectrum characteristics energy transfer rare-earth ions judd-ofelt analysis optical characterization absorption intensities spectral properties mu-m laser ho3+ fluorescence garnets