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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.  
Enhancing the Performance of the Half Tin and Half Lead Perovskite Solar Cells by Suppression of the Bulk and Interfacial Charge Recombination 期刊论文  OAI收割
ADVANCED MATERIALS, 2018, 卷号: 30, 期号: 35
作者:  Shao, Shuyan;  Cui, Yong;  Duim, Herman;  Qiu, Xinkai;  Dong, Jingjin
  |  收藏  |  浏览/下载：28/0  |  提交时间：2019/04/09
Particle-hole bound states of dipolar molecules in an optical lattice 期刊论文  OAI收割
CHINESE PHYSICS B, 2013, 卷号: 22, 期号: 9
Zhang, YC; Wang, HT; Shen, SQ; Liu, WM
收藏  |  浏览/下载：24/0  |  提交时间：2014/01/16
Changes in Cloud Cover, Precipitation, and Summer Temperature in North America from 1982 to 2009 SCI/SSCI论文  OAI收割
2013
Tang Q. H.; Leng G. Y.
收藏  |  浏览/下载：20/0  |  提交时间：2014/12/24
Electronic inhomogeneity in a Kondo lattice 期刊论文  OAI收割
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA, 2011, 卷号: 108, 期号: 17, 页码: 6857
Bauer, ED; Yang, YF; Capan, C; Urbano, RR; Miclea, CF; Sakai, H; Ronning, F; Graf, MJ; Balatsky, AV; Movshovich, R; Bianchi, AD; Reyes, AP; Kuhns, PL; Thompson, JD; Fisk, Z
收藏  |  浏览/下载：40/0  |  提交时间：2013/09/17
Excitonic properties of vertically aligned ZnO nanotubes under high-density excitation (EI CONFERENCE) 会议论文  OAI收割
Lu Y. M.; Liang H. W.; Shen D. Z.; Zhang Z. Z.; Zhang J. Y.; Zhao D. X.; Liu Y. C.; Fan X. W.
收藏  |  浏览/下载：13/0  |  提交时间：2013/03/25
In this paper  highly oriented and vertically arranged ZnO nanotubes are prepared on Al2O3 (0 0 0 1) substrate without employing any metal catalysts by plasma-assisted molecular beam epitaxy. The photoluminescence (PL) spectra at room temperature are studied under high excitation densities. Under lower excitation density (60 kW/cm2)  PL spectrum shows that one strong free exciton emission (FE) locates at 3.306 eV. As the excitation density increases up to 200 kW/cm2  a new emission peak (Pn) located at low-energy side of FE is attributed to the spontaneous emission due to an exciton-exciton (Ex-E x) scattering process from two ground state excitons  where one exciton is recombined by emitting a photon and the other is scattered into the excited states of n=2  3  4.... Under excitation density of 300 kW/cm 2  the stimulated emission originating from Ex-E x scattering is obtained. When the excitation density is above 580 kW/cm2  the emission from electron-hole plasma is observed in low-energy side of the P band and indicates a typical superradiation recombination processes with increasing excitation density. 2006 Elsevier B.V. All rights reserved.  
Electron resonant tunneling through InAs/GaAs quantum dots embedded in a Schottky diode with an AlAs insertion layer 期刊论文  OAI收割
journal of the electrochemical society, 2006, 卷号: 153, 期号: 7, 页码: g703-g706
作者:  Ye XL;  Xu B;  Jin P
收藏  |  浏览/下载：105/0  |  提交时间：2010/04/11
CU K-EDGE POLARIZED X-RAY-ABSORPTION NEAR-EDGE STRUCTURE OF BI2CASR2CU2O8 期刊论文  OAI收割
PHYSICAL REVIEW B, 1991, 卷号: 44, 期号: 9, 页码: 4560
BIANCONI, A; LI, CX; CAMPANELLA, F; DELLALONGA, S; PETTITI, I; POMPA, M; TURTU, S; UDRON, D
收藏  |  浏览/下载：20/0  |  提交时间：2013/09/17
ONE-ELECTRON EXCITATIONS AND SHAKE UP SATELLITES IN CU K-EDGE X-RAY ABSORPTION NEAR EDGE STRUCTURE (XANES) OF LA2CUO4 BY FULL MULTIPLE-SCATTERING ANALYSIS IN REAL SPACE 期刊论文  OAI收割
PHYSICA C, 1991, 卷号: 175, 期号: 3-4, 页码: 369
LI, CX; POMPA, M; CASTELLANO, AC; DELLALONGA, S; BIANCONI, A
收藏  |  浏览/下载：33/0  |  提交时间：2013/09/24