中国科学院机构知识库网格系统: 检索

浏览/检索结果: 共4条，第1-4条

帮助

条数/页：排序方式：
	Periodicity Search on X-Ray Bursts of SGR J1935+2154 Using 8.5 yr of Fermi/GBM Data 期刊论文 OAI收割 The Astrophysical Journal, 2021, 卷号: 923, 页码: L30 作者: HXMT \| 收藏 \| 浏览/下载：22/0 \| 提交时间：2022/02/08 2008 1471 Astrophysics - High Energy Astrophysical Phenomena Abstract: We performed a systematic search for X-ray bursts of the SGR J1935+2154 using the Fermi Gamma-ray Burst Monitor continuous data dated from 2013 January to 2021 October. Eight bursting phases, which consist of a total of 353 individual bursts, are identified. We further analyze the periodic properties of our sample using the Lomb-Scargle periodogram. The result suggests that those bursts exhibit a period of ~238 days with a ~63.2% duty cycle. Based on our analysis, we further predict two upcoming active windows of the X-ray bursts. Since 2021 July, the beginning date of our first prediction has been confirmed by the ongoing X-ray activities of the SGR J1935+2154.
	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：28/0 \| 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.
	Evaluation and improvement of coastal GNSS reflectometry sea level variations from existing GNSS stations in Taiwan 期刊论文 OAI收割 ADVANCES IN SPACE RESEARCH, 2019, 卷号: 63, 期号: 3, 页码: 1280-1288 作者: Lee, Chi-Ming; Kuo, Chung-Yen; Sun, Jian; Tseng, Tzu-Pang; Chen, Kwo-Hwa \| 收藏 \| 浏览/下载：20/0 \| 提交时间：2019/04/10 Global navigation satellite systems (GNSS) Signal-to-noise ratio (SNR) Lomb-Scargle periodogram (LSP) Tidal harmonic analysis
	The possible influence of solar activity on Indian summer monsoon rainfall 期刊论文 OAI收割 APPLIED GEOPHYSICS, 2008, 卷号: 4, 期号: 3, 页码: 231-237 作者: Ma Lihua; Han Yanben; Yin Zhiqiang 收藏 \| 浏览/下载：14/0 \| 提交时间：2017/06/23 summer monsoon rainfall solar activity scargle periodogram wavelet transform