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	Constraining the X-Ray-Infrared Spectral Index of Second-timescale Flares from SGR 1935+2154 with Palomar Gattini-IR 期刊论文 OAI收割 The Astrophysical Journal, 2020, 卷号: 901, 页码: L7 作者: HXMT \| 收藏 \| 浏览/下载：24/0 \| 提交时间：2022/02/08 Radio transient sources Magnetars Soft gamma-ray repeaters 2008 992 1471 Astrophysics - High Energy Astrophysical Phenomena Astrophysics - Instrumentation and Methods for Astrophysics Abstract: The Galactic magnetar SGR 1935+2154 has been reported to produce the first example of a bright millisecond-duration radio burst (FRB 200428) similar to the cosmological population of fast radio bursts (FRBs). The detection of a coincident bright X-ray burst represents the first observed multiwavelength counterpart of an FRB. However, the search for similar emission at optical wavelengths has been hampered by the high inferred extinction on the line of sight. Here, we present results from the first search for second-timescale emission from the source at near-infrared (NIR) wavelengths using the Palomar Gattini-IR observing system in the J band, enabled by a novel detector readout mode that allows short exposure times of ?0.84 s with 99.9% observing efficiency. With a total observing time of ?12 hr (?47,728 images) during its 2020 outburst, we place median 3Ҡlimits on the second-timescale NIR fluence of ?18 Jy ms (13.1 AB mag). The corresponding extinction-corrected limit is ?125 Jy ms for an estimated extinction of A_J = 2.0 mag. Our observations were sensitive enough to easily detect an NIR counterpart of FRB 200428 if the NIR emission falls on the same power law as observed across its radio to X-ray spectrum. We report nondetection limits from epochs of four simultaneous X-ray bursts detected by the Insight-HXMT and NuSTAR telescopes during our observations. These limits provide the most stringent constraints to date on fluence of flares at 10¹⁴ Hz, and constrain the fluence ratio of the NIR emission to coincident X-ray bursts to R_NIR ? 0.025 (fluence index ?0.35).
	Variation in grain size distribution in debris flow 期刊论文 OAI收割 JOURNAL OF MOUNTAIN SCIENCE, 2015, 卷号: 12, 期号: 3, 页码: 682-688 作者: Li Yong; Wang Bao-liang; Zhou Xiao-jun; Gou Wan-chun 收藏 \| 浏览/下载：31/0 \| 提交时间：2015/06/01 Debris flow Grain size distribution Flow fluctuation Power-law constraints
	Relationship between grain composition and debris flow characteristics: a case study of the Jiangjia Gully in China 期刊论文 OAI收割 LANDSLIDES, 2015, 卷号: 12, 期号: 1, 页码: 19-28 作者: Li, Yong; Liu, Jingjing; Su, Fenghuan; Xie, Jiang; Wang, Baoliang 收藏 \| 浏览/下载：33/0 \| 提交时间：2014/12/02 Debris flow Grain size distribution Flow fluctuation Power law constraints
	Holographic dark energy reexamined 期刊论文 OAI收割 PHYSICAL REVIEW D, 2005, 卷号: 72, 期号: 4, 页码: - 作者: Gong, YG; Wang, B; Zhang, YZ; Gong, YG , Chongqing Univ Posts & Telecommun, Coll Elect Engn, Chongqing 400065, Peoples R China. \| 收藏 \| 浏览/下载：15/0 \| 提交时间：2012/08/30 Probe Wmap Observations Hubble-space-telescope Cardy-verlinde Formula Cosmological Constant Friedmann Equation Power Spectrum Entropy Bounds 2nd Law Constraints Supernovae