中国科学院机构知识库网格
Chinese Academy of Sciences Institutional Repositories Grid
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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:25/0  |  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).  
The study on the temperature influence of the grain near infrared spectrum analysis (EI CONFERENCE) 会议论文  OAI收割
ICO20: Optical Information Processing, August 21, 2005 - August 26, 2005, Changchun, China
作者:  
Zhang J.;  Chen X.;  Chen X.;  Chen X.;  Zhang J.
收藏  |  浏览/下载:27/0  |  提交时间:2013/03/25
Near-infrared spectroscopy was used to examine unmodified wheat powder at temperatures of 14-65C. A self-regulating diffuse reflected assembly was used to permit collection of spectra of powder samples. Changes to the shape and peak location of the 1400-1500nm and 1900-1950nm water absorption bands  2000-2050  2070-2110 and 2250-2300nm bands were measured as temperature varied. Results indicated that temperature changes resulted in slight changes to the water absorption bands in 1400-1500nm and 1900-1950nm regions. From 14-65C  the 1400-1500nm and 2050-2150nm band shifted approximately 10nm and 16nm toward shorter wavelengths  and 2000-2050nm band shifted approximately 14nm toward longer wavelengths. In addition few numbers of samples cannot constitute good temperature insensitive calibration model even though the spectra were obtained at wide temperature condition.  
Two-dimensional silicon-based photonic crystal slab with partial air-bridge 期刊论文  OAI收割
International Journal of Nanoscience, 2006, 卷号: 5, 期号: 6, 页码: 683
Tian, J; Han, SZ; Cheng, BY; Feng, S; Li, ZY; Ren, C; Zhang, DZ
收藏  |  浏览/下载:26/0  |  提交时间:2013/09/23
Two-dimensional silicon-based photonic crystal slab with partial air-bridge 期刊论文  OAI收割
ACTA PHYSICA SINICA, 2005, 卷号: 54, 期号: 3, 页码: 1218
Tian, J; Han, SZ; Cheng, BY; Li, ZY; Feng, S; Zhang, DZ; Jin, AZ
收藏  |  浏览/下载:20/0  |  提交时间:2013/09/23
Enlarging a photonic band gap by using insertion 期刊论文  OAI收割
PHYSICAL REVIEW B, 2000, 卷号: 61, 期号: 3, 页码: 1892
Zhang, XD; Zhang, ZQ; Li, LM; Jin, C; Zhang, D; Man, B; Cheng, B
收藏  |  浏览/下载:23/0  |  提交时间:2013/09/17
HIGHLY EFFICIENT SELF-PUMPED PHASE-CONJUGATION IN BARIUM-TITANATE CRYSTALS 期刊论文  OAI收割
JOURNAL OF THE OPTICAL SOCIETY OF AMERICA B-OPTICAL PHYSICS, 1994, 卷号: 11, 期号: 10, 页码: 1992
ZHANG, ZG; ZHANG, YH; YANG, CX; KANG, J; ZHENG, SH; ZHU, Y; CHEN, YS; WU, X; FU, PM
收藏  |  浏览/下载:20/0  |  提交时间:2013/09/17
MECHANISM TRANSFORMATION WITH WAVELENGTH OF SELF-PUMPED PHASE-CONJUGATION IN BATIO3CE 期刊论文  OAI收割
OPTICS LETTERS, 1994, 卷号: 19, 期号: 9, 页码: 610
LIAN, YW; DOU, SX; GAO, H; ZHU, Y; WU, X; YANG, CX; YE, PX
收藏  |  浏览/下载:16/0  |  提交时间:2013/09/18