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Spin Evolution of the Magnetar SGR J1935+2154 期刊论文  OAI收割
RESEARCH IN ASTRONOMY AND ASTROPHYSICS, 2024, 卷号: 24, 期号: 1
作者:  Ge, Ming-Yu;  Yang, Yuan-Pei;  Lu, Fang-Jun;  Zhou, Shi-Qi;  Ji, Long
  |  收藏  |  浏览/下载：40/0  |  提交时间：2024/03/29
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：26/0  |  提交时间：2022/02/08
No pulsed radio emission during a bursting phase of a Galactic magnetar 期刊论文  OAI收割
Nature, 2020, 卷号: 587, 页码: 63-65
作者:  HXMT
  |  收藏  |  浏览/下载：52/0  |  提交时间：2022/02/08
Astrophysics - High Energy Astrophysical Phenomena  Abstract: Fast radio bursts (FRBs) are millisecond-duration radio transients of unknown physical origin observed at extragalactic distances1-3. It has long been speculated that magnetars are the engine powering repeating bursts from FRB sources4-13, but no convincing evidence has been collected so far14. Recently, the Galactic magnetar SRG 1935+2154 entered an active phase by emitting intense soft íray bursts15. One FRB-like event with two peaks (FRB 200428) and a luminosity slightly lower than the faintest extragalactic FRBs was detected from the source, in association with a soft íray/hard-X-ray flare18-21. Here we report an eight-hour targeted radio observational campaign comprising four sessions and assisted by multi-wavelength (optical and hard-X-ray) data. During the third session, 29 soft-íray repeater (SGR) bursts were detected in íray energies. Throughout the observing period, we detected no single dispersed pulsed emission coincident with the arrivals of SGR bursts, but unfortunately we were not observing when the FRB was detected. The non-detection places a fluence upper limit that is eight orders of magnitude lower than the fluence of FRB 200428. Our results suggest that FRB-SGR burst associations are rare. FRBs may be highly relativistic and geometrically beamed, or FRB-like events associated with SGR bursts may have narrow spectra and characteristic frequencies outside the observed band. It is also possible that the physical conditions required to achieve coherent radiation in SGR bursts are difficult to satisfy, and that only under extreme conditions could an FRB be associated with an SGR burst.  
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：28/0  |  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 AJ = 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 RNIR ? 0.025 (fluence index ?0.35).  
泛在制造信息感知与网络技术可能取得重大突破 期刊论文  OAI收割
中国科学院院刊, 2013, 卷号: 28, 期号: 5, 页码: 621-623
作者:  王天然
收藏  |  浏览/下载：44/0  |  提交时间：2014/04/16
海葵化学成分及生物活性研究进展 期刊论文  OAI收割
海洋科学, 2013, 卷号: 37, 期号: 12, 页码: 122-131
史文军; 秦松; 张朝晖; 吴建平
收藏  |  浏览/下载：48/0  |  提交时间：2014/07/07
序 期刊论文  OAI收割
环境科学, 2011, 期号: 12
郝郑平
收藏  |  浏览/下载：16/0  |  提交时间：2011/12/29
磷、硼微合金化——一种发展高性能变形高温合金的新途径 期刊论文  OAI收割
中国基础科学, 2005, 期号: 6, 页码: 15-16
孙文儒; 宋洪伟; 郭守仁; 胡壮麒
收藏  |  浏览/下载：18/0  |  提交时间：2012/04/12
激光脱毛技术 期刊论文  OAI收割
光机电信息, 2001, 期号: 05, 页码: 13-16
王红妍; 陈宇
收藏  |  浏览/下载：29/0  |  提交时间：2013/03/11
TDRSS轨道确定方法的初步研究 期刊论文  OAI收割
飞行器测控技术, 1992, 期号: 2, 页码: 9-18
陆本魁; 戎鹏志; 郑卫星
收藏  |  浏览/下载：38/0  |  提交时间：2012/03/03