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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：61/0 \| 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.
	Multi-component elastic reverse time migration based on the P- and S-wave separated velocity-stress equations 期刊论文 OAI收割 JOURNAL OF APPLIED GEOPHYSICS, 2015, 卷号: 112, 页码: 62-78 作者: Gu, Bingluo; Li, Zhiyuan; Ma, Xiaona; Liang, Guanghe \| 收藏 \| 浏览/下载：20/0 \| 提交时间：2018/09/26 Elastic reverse time migration The P- and S-separated elastic equations Crosstalk Polarity-reversal Phase and amplitude attributes
	Multi-component elastic reverse time migration based on the P- and S-wave separated velocity-stress equations 期刊论文 OAI收割 JOURNAL OF APPLIED GEOPHYSICS, 2015, 卷号: 112, 页码: 62-78 作者: Gu, Bingluo; Li, Zhiyuan; Ma, Xiaona; Liang, Guanghe \| 收藏 \| 浏览/下载：20/0 \| 提交时间：2018/09/26 Elastic reverse time migration The P- and S-separated elastic equations Crosstalk Polarity-reversal Phase and amplitude attributes
	Indistinguishability of orthogonal time-separated bell states 期刊论文 OAI收割 CHINESE PHYSICS B, 2008, 卷号: 17, 期号: 9, 页码: 3194-3197 作者: Tan Yong-Gang; Cai Qing-Yu; Shi Ting-Yun 收藏 \| 浏览/下载：18/0 \| 提交时间：2015/10/13 bell states time-separated indistinguishability
	Optical thin films for high power LD-pumped Nd:YVO4 457nm blue laser (EI CONFERENCE) 会议论文 OAI收割 ICO20: Optical Design and Fabrication, August 21, 2005 - August 26, 2005, Changchun, China Bu Y.; Zheng Q.; Xue Q.; Qian L. 收藏 \| 浏览/下载：21/0 \| 提交时间：2013/03/25 The expanding field of LD-pumped solid state lasers forms an extraordinary challenge for developing the optical coatings. Optical thin films for LD-pumped Nd:YVO4/LBO blue laser at 457nm was presented in this paper based on lower gain laser line action theory including spectral beam dividers and doubling antireflecting multilayer coatings. To achieve 914nm laser action and 457nm blue light high output power the coating specifications of laser resonator was analyzed. The transmittance/reflectance spectrum request was effectively separated by adopting high tuned radio stack simultaneously the spectrum request was reasonably distributed on the two resonator facet reflectivity for restrain the other laser lines such as1064nm and1342nm. The dielectric high reflective laser mirror and antireflecting coatings for 457nm laser were manufactured by double ion beam sputtering technique which is controlled by a time-power monitoring. Using type-I critical phase-matching LBO crystal 457nm blue laser is obtained by 914nm intracavity frequency doubling. The maximum laser output power of 1.5W is obtained when incident pump laser of 15W is used.