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	Synchronous X-ray/Optical QPOs from the Black Hole LMXB MAXI J1820+070 期刊论文 OAI收割 Monthly Notices of the Royal Astronomical Society, 2021 作者: HXMT \| 收藏 \| 浏览/下载：59/0 \| 提交时间：2022/02/08 black hole physics Low Mass X-ray Binaries accretion accretion discs stars: individual (MAXI J1820+070) Astrophysics - High Energy Astrophysical Phenomena Abstract: We present high-speed optical photometry from SAAO and SALT on the black hole LMXB MAXI J1820+070 (ASSASN-18ey), some of it simultaneous with NICER, Swift and Insight-HXMT X-ray coverage. We detect optical Quasi-Periodic Oscillations (QPOs) that move to higher frequencies as the outburst progresses, tracking both the frequency and evolution of similar X-ray QPOs previously reported. Correlated X-ray/optical data reveal a complex pattern of lags, including an anti-correlation and a sub-second lag that evolve over the first few weeks of outburst. They also show correlated components separated by a lag equal to the QPO period roughly centered on zero lag, implying that the inter-band variability is strongly and consistently affected by these QPOs at a constant phase lag of roughly ±Ю The synchronisation of X-ray and optical QPOs indicates that they must be produced in regions physically very close to each other we thus propose that they can be explained by a precessing jet model, based on analogies with V404 Cyg and MAXI J1348-630.
	Detection of Flare Multiperiodic Pulsations in Mid-ultraviolet Balmer Continuum, Lyl Hard X-Ray, and Radio Emissions Simultaneously 期刊论文 OAI收割 The Astrophysical Journal, 2021, 卷号: 921, 页码: 179 作者: HXMT \| 收藏 \| 浏览/下载：32/0 \| 提交时间：2022/02/08 Solar flares Solar oscillations Solar ultraviolet emission Solar x-ray emission Solar radio emission 1496 1515 1533 1536 1522 Astrophysics - Solar and Stellar Astrophysics Abstract: Quasi-periodic pulsations (QPPs), which usually appear as temporal pulsations of the total flux, are frequently detected in the light curves of solar/stellar flares. In this study, we present the investigation of nonstationary QPPs with multiple periods during the impulsive phase of a powerful flare on 2017 September 6, which were simultaneously measured by the Hard X-ray Modulation Telescope (Insight-HXMT), as well as the ground-based BLENSW. The multiple periods, detected by applying a wavelet transform and Lomb-Scargle periodogram to the detrended light curves, are found to be ~20-55 s in the Ly`and mid-ultraviolet Balmer continuum emissions during the flare impulsive phase. Similar QPPs with multiple periods are also found in the hard X-ray emission and low-frequency radio emission. Our observations suggest that the flare QPPs could be related to nonthermal electrons accelerated by the repeated energy release process, i.e., triggering of repetitive magnetic reconnection, while the multiple periods might be modulated by the sausage oscillation of hot plasma loops. For the multiperiodic pulsations, other generation mechanisms could not be completely ruled out.
	Changes of gray matter volume and amplitude of lowfrequency oscillations in amnestic MCI An integrative multimodal MRI study 期刊论文 OAI收割 Acta Radiologica, 2015, 卷号: 56, 期号: 5, 页码: 614–621 作者: Zhi-Lian Zhao; Feng-Mei Fan; Jie Lu; Hui-Jie Li; Long-Fei Jia \| 收藏 \| 浏览/下载：29/0 \| 提交时间：2018/04/27 aMCI resting-state fMRI low-frequency oscillations VBM
	First observations of tidal oscillations by an MF radar over Kunming (25.6 degrees N, 103.8 degrees E) 期刊论文 OAI收割 JOURNAL OF ATMOSPHERIC AND SOLAR-TERRESTRIAL PHYSICS, 2012, 卷号: 78-79, 页码: 44-52 作者: Zhao, Lei; Chen, Jinsong; Ding, Zonghua; Li, Na; Zhao, Zhenwei 收藏 \| 浏览/下载：31/0 \| 提交时间：2014/12/15 Medium frequency radar Tidal oscillations Kunming Low latitude