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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 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).  
Evaluation of growth characteristics of Aspergillus parasiticus inoculated in different culture media by shortwave infrared (SWIR) hyperspectral imaging 期刊论文  OAI收割
JOURNAL OF INNOVATIVE OPTICAL HEALTH SCIENCES, 2018, 卷号: 11, 期号: 5, 页码: 1850031
作者:  
Chu, Xuan;  Wang, Wei;  Ni, Xinzhi;  Zheng, Haitao;  Zhao, Xin
  |  收藏  |  浏览/下载:102/0  |  提交时间:2019/09/24
Photonic anti-counterfeiting using structural colors derived from magnetic-responsive photonic crystals with double photonic bandgap heterostructures 期刊论文  OAI收割
JOURNAL OF MATERIALS CHEMISTRY, 2012, 卷号: 22, 期号: 22, 页码: 11048
Hu, HB; Chen, QW; Tang, J; Hu, XY; Zhou, XH
收藏  |  浏览/下载:30/0  |  提交时间:2013/09/24
Linear-mode characters of near-infrared wavelength InGaAs APDs for optical communication 会议论文  OAI收割
4th International Symposium on Photoelectronic Detection and Imaging (ISPDI) - Advances in Infrared Imaging and Applications, Beijing, PEOPLES R CHINA, 2011
作者:  
He Wei;  Du Ke-ming;  Wang Chao;  Sun Zhi-bin;  Jiang Yuan-da
收藏  |  浏览/下载:35/0  |  提交时间:2014/12/15
Method for obtaining real temperature of space object by using the ratio of emissivity at different wavelengths (EI CONFERENCE) 会议论文  OAI收割
4th International Symposium on Advanced Optical Manufacturing and Testing Technologies: Optical Test and Measurement Technology and Equipment, November 19, 2008 - November 21, 2008, Chengdu, China
Guo-Qiang W.; Tao C.; Jian-Li W.
收藏  |  浏览/下载:33/0  |  提交时间:2013/03/25
The infrared radiation character (temperature and efficiency radiation area) of a space object is an important characteristic  we can judge the state of the object working in orbit by measuring temperature and variety. Due to lower temperature of the object and far distance between the object and the earth  the infrared radiation signal is faintness  therefore temperature and the infrared radiation character is difficult to measure. There are several methods to measure the temperature of the object in theory and each one has its applicability respectively  such as applying Wien Law to compute temperature  based on Stefan-Bolzmann law to compute temperature and utilizing multi-spectrum detector to measure temperature As a whole these methods are based on the hypothesis that the object is a Black-body or the radiance emissivity is constant. In fact  homochromatic radiance of object is not a constant but a function that changes with wavelength. Since the problem that an object whose homochromatic radiance s not a constant which results in temperature can not be computed accurately  we bring forward a method to contrast the luminance of the object at different wavelengths and deduce the relationship among homochromatic radiance and wavelength and the temperature of Black-body  from which we can compute real temperature of object. 2009 SPIE.  
Locally resonant phononic woodpile: A wide band anomalous underwater acoustic absorbing material 期刊论文  OAI收割
Applied Physics Letter, 2009, 卷号: 95, 期号: 10, 页码: 104101
作者:  
Jiang H(姜恒);  Wang YR(王育人);  Zhang ML;  Hu YP(胡燕萍);  Lan D(蓝鼎)
收藏  |  浏览/下载:1353/159  |  提交时间:2009/08/03
Optical system design with high resolution and large field of view for the remote sensor (EI CONFERENCE) 会议论文  OAI收割
Chang J.; Weng Z.-C.; Wang Y.-T.; Cheng D.-W.; Jiang H.-L.
收藏  |  浏览/下载:29/0  |  提交时间:2013/03/25
In this paper  we are presenting a design method and its results for a space optical system with high resolution and wide field of view. This optical system can be used both in infrared and visible configurations. The designing of this system is based on an on-axis three-mirror anastigmatic (TMA) system. Here the on-axis concept allows wide field of view (FOV) enabling a diversity of designs available for the Multi-Object Spectrometer instruments optimized for low scattered and low emissive light. The available FOVs are upto 1 in both spectrum ranges  whereas the available aperture range is F/15 - F/10. The final optical system is a three-mirror telescope with two on-axis and one off-axis segment and its resolution is 0.3m or even lower. The distinguished feature of this design is that it maintains diffraction-limited image at wide wavelengths. The technological developments in the field of computer generated shaping of large-sized optical surface details with diffraction-limited imagery have opened new avenues towards the designing techniques. Such techniques permit us to expand these technological opportunities to fabricate the aspherical off-axis mirrors for a complex configuration.  
不同玻璃组分对掺铒碲酸盐玻璃光谱性质的影响 期刊论文  OAI收割
光子学报, 2008, 卷号: 37, 期号: s1
于春雷; 温磊; 汪国年; 张军杰; 胡丽丽
收藏  |  浏览/下载:1307/380  |  提交时间:2009/09/24
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:26/0  |  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:25/0  |  提交时间:2013/09/23