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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：22/0 \| 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).
	Investigation of the near-threshold cluster resonance in C-14 期刊论文 OAI收割 CHINESE PHYSICS C, 2018, 卷号: 42, 期号: 7, 页码: 074003 作者: Bai, Zhen; Yang, Yan-Yun; Jin, Shi-Lun; Lu, Fei; Zang, Hong-Liang \| 收藏 \| 浏览/下载：175/0 \| 提交时间：2018/07/16 cluster decay linear-chain-state high detection efficiency inelastic excitation
	Investigation of the near-threshold cluster resonance in C-14 期刊论文 OAI收割 CHINESE PHYSICS C, 2018, 卷号: 42, 期号: 7, 页码: 74003 作者: Niu, CY; Wu, HY; Liu, Y; Gao, J; Ma, JB \| 收藏 \| 浏览/下载：44/0 \| 提交时间：2019/09/24 cluster decay linear-chain-state high detection efficiency inelastic excitation
	Study on spectrograph for ionosphere: A broadband imaging instrument prototype for far-ultraviolet (EI CONFERENCE) 会议论文 OAI收割 International Symposium on Photoelectronic Detection and Imaging 2011: Space Exploration Technologies and Applications, May 24, 2011 - May 26, 2011, Beijing, China 作者: Wang S.-R.; Lin G.-Y.; Yu L. 收藏 \| 浏览/下载：35/0 \| 提交时间：2013/03/25 Current research on space-based exploration for the ionosphere needs more advanced technologies. Because the spectral signals in the ionosphere distributing basically in the far-ultraviolet waveband are very weak. Usual spectrometer structures and detectors such as CCD can't receive enough information. Based on this principle of atmospheric sounding the imaging spectrometer prototype for ionosphere detection application was designed to solve the problem. This prototype consists of the telescope and the imaging spectrometer. The simple structure and small number of mirrors can help higher transmission efficiency be achieved and weak signals detection be implemented. The telescope is an off-axis parabolic mirror and the spectrometer is a modified Czerny-Turner spectral imaging system. Modified Czerny-Turner spectrometer contains a spherical mirror a fixed plane grating and a toroidal mirror. By adjusting the incident angle to the collimating mirror and using toroidal mirror coma and astigmatism were corrected well. We also optimize distances between the grating to the focusing mirror and the focusing mirror to the image plane to improve disadvantages of traditional Czerny-Turner structure. Designed results demonstrate that aberrations are substantially corrected and high image quality can be obtained in broad waveband. The photon counting Wedge-Strip-Anode detector with micro-channel planes as the receiving plane is accepted for the instrument prototype. The other photon counting 2-D detector responding well for weak light such as Cross-Delay line detector and MAMA detector can also be used for detection. The calibration and performances testing system is made of a vacuum system a deuterium lamp a monochrometer and the instrument prototype. Results obtained from the experiment show that the spectral resolution is 2.4 nm and the spatial resolution is 80 m. The other calibration experiments are running. The technology of the spectrometer prototype is important for the research and applications of ionosphere remote sensing. 2011 SPIE.
	Precision detection of CCD splicing based on template matching algorithm (EI CONFERENCE) 会议论文 OAI收割 IEEE 2nd International Conference on Computing, Control and Industrial Engineering, CCIE 2011, August 20, 2011 - August 21, 2011, Wuhan, China 作者: Zhang X.; Zhang X.; Yang L.; Zhang X.; Yang L. 收藏 \| 浏览/下载：32/0 \| 提交时间：2013/03/25 The remote sensing camera in large field and wide cover needs CCD with enough pixels. But the existing CCD cannot satisfy the practical needs. Therefore several pieces of CCD which has insufficient pixels are spliced to get a long CCD array with plenty of pixels. The precision requirements of CCD splicing are very strict so that the same high accuracies are required in the precision detection of CCD splicing. When detecting precision of CCD splicing the graphical markers with simple geometric structure in the CCD package are selected as templates. The position precision data of the graphical markers in each CCD are obtained using the template matching algorithm. Using the unified objective templates the focal plane which has multi-chip of CCD is detected by template matching algorithm. Experiment results show that the template matching algorithm can enhance the located precision of each CCD to 0.347m. The splicing precision detection with template matching algorithm can avoid the subjective error caused by the conventional detection method. And its results are more accurate. In addition without manual intervention in the process of precision detection the efficiency of precision detection is improved. 2011 IEEE.
	Measuring instrument for radial composite deviations of high-precision master gear (EI CONFERENCE) 会议论文 OAI收割 6th International Symposium on Precision Engineering Measurements and Instrumentation, August 8, 2010 - August 11, 2010, Hangzhou, China 作者: Zhang Y.; Wang L.; Wang L.; Wang L. 收藏 \| 浏览/下载：36/0 \| 提交时间：2013/03/25 During double flank rolling composite detection the radial composite deviations of master gears has been existed and transferred to the measured gear by the primary harmonic curve. In order to improve measurement accuracy a measuring instrument is developed for radial composite deviations of high-precision master gear in the paper. This instrument uses the structure of spring-suspend swing span to overcome the shortcomings of large rotation errors low sensitivity low resolution and large measuring force appearing in the traditional combination-type gear inspection instrument. Artificial intelligence technology is used to improve the efficiency and accuracy of this instrument. The result is that the measuring apparatus is able to meet the requirement and improve efficiency through the measuring experiments on master gears of precision grade 2 with modulus 2 mm and 3 mm respectively. 2010 SPIE.
	Auto-detection system of photoelectric encoder based on DSP (EI CONFERENCE) 会议论文 OAI收割 2010 2nd International Conference on Industrial and Information Systems, IIS 2010, July 10, 2010 - July 11, 2010, Dalian, China 作者: Wan Q.-H.; Qi L.-L.; Liang L.-H.; Lu X.-R.; Du Y.-C. 收藏 \| 浏览/下载：19/0 \| 提交时间：2013/03/25 To improve the automatic detection efficiency of photoelectric encoder an auto-detection system of photoelectric encoder is designed using DSP (TMS320F2812) as the core device. A 21-bit high accuracy photoelectric encoder is used as the angle standard. It is connected to the detected photoelectric encoder coaxially. They will rotate synchronously under the driving of electric motor. Data acquisition and processing system collects the angular data of the two photoelectric encoders at the same angular position and calculates the angular error of detected photoelectric encoder. Then the data is put into computer. The computer will display the data error. The result of experiment shows that the system could detect encoder whose bit-number below 19 the detecting person could be reduced to one and the detecting speed could be increased to 8-10 times. 2010 IEEE.