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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.
	FCC Physics Opportunities: Future Circular Collider Conceptual Design Report Volume 1 期刊论文 OAI收割 EUROPEAN PHYSICAL JOURNAL C, 2019 作者: Abada, A; Abbrescia, M; AbdusSalam, SS; Abdyukhanov, I; Fernandez, JA \| 收藏 \| 浏览/下载：151/0 \| 提交时间：2019/07/19 ELECTROWEAK PHASE-TRANSITION BY-LIGHT SCATTERING DEEP INELASTIC-SCATTERING STRANGE BARYON PRODUCTION DARK-MATTER RADIATIVE-CORRECTIONS E(+)E(-) COLLISIONS TRANSVERSE-MOMENTUM TOP-QUARK BRANCHING FRACTIONS
	Assessment of surface roughness by use of soft x-ray scattering (EI CONFERENCE) 会议论文 OAI收割 Soft X-Ray Lasers and Applications VIII, August 4, 2009 - August 6, 2009, San Diego, CA, United states Yan-li M.; Yong-gang W.; Shu-yan C.; Bo C. 收藏 \| 浏览/下载：32/0 \| 提交时间：2013/03/25 A soft x-ray reflectometer with laser produced plasma source has been designed which can work from wavelength 8nm to 30 nm and has high performance. Using the soft x-ray reflectometer above the scattering light distribution of silicon and zerodur mirrors which have super-smooth surfaces could be measured at different incidence angle and different wavelength. The measurement when the incidence angle is 2 degree and the wavelength is 1 lnm has been given in this paper. A surface scattering theory of soft x-ray grazing incidence optics based on linear system theory and an inverse scattering mathematical model is introduced. The vector scattering theory of soft x-ray scattering also is stated in detail. The scattering data are analyzed by both the methods above respectively to give information about the surface profiles. On the other hand both the two samples are measured by WYKO surface profiler and the surface roughness of the silicon and zerodur mirror is 1.3 nm and 1.5nm respectively. The calculated results are in quantitative agreement with those measured by WYKO surface profiler which indicates that soft x-ray scattering is a very useful tool for the evaluation of highly polished surfaces. But there still some difference among the results of different theory and WYKO and the possible reasons of such difference have been discussed in detail. 2009 SPIE.
	Scaling and analyzing the influence of fluid surface of fluid with nano-granular through speckle pattern experiment (EI CONFERENCE) 会议论文 OAI收割 3rd International Symposium on Advanced Optical Manufacturing and Testing Technologies, AOMATT 2007: Advanced Optical Manufacturing Technologies, July 8, 2007 - July 12, 2007, Chengdu, China 作者: Wang X.; Wang Y.; Wang Y.; Wang Y.; Wang Y. 收藏 \| 浏览/下载：23/0 \| 提交时间：2013/03/25 An optical system with double beam interference system was designed to measure the movement of nano-particles in fluid with laser speckle technology. In order to investigate the influence of the scattering light generated from liquid surface on speckle patterns the liquid surface contour was dynamically detected by WYKO during nano-particle movement. The result demonstrates that the fluctuation of fluid surface is slight. Meanwhile in order to further analyze this effect a piece of ground glass was employed. The process of ground glass to be polished to optical glass was studied and tested continuously using WYKO and laser speckle technology. And then the speckle patterns generated from kerosene fluid surface were studied. By contrast the results show that the fluid surface is transparent to the measurement wavelength. The influence of the surface of fluid can be neglected. Furthermore the conclusion illustrates that laser speckle technique is an effective and reliable method to study the movement of nano-granular in fluid.
	Light-scattering study of polyelectrolyte hollow capsules 期刊论文 OAI收割 CHINESE JOURNAL OF POLYMER SCIENCE, 2004, 卷号: 22, 期号: 2, 页码: 111-115 作者: Zhang, YJ; Guan, Y; Yang, SG; Xu, J; Miao, XP \| 收藏 \| 浏览/下载：18/0 \| 提交时间：2019/04/09 Layer-by-layer (Lbl) Self-assembly Hollow Capsule Silver Halide Laser Light Scattering