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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：33/0 \| 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).
	脉冲激光抽运铷原子钟研究会议论文 OAI收割第二届中国卫星导航学术年会, 中国上海, 2011 杜志静; 赵文宇; 刘杰; 刘丹丹; 张首刚收藏 \| 浏览/下载：30/0 \| 提交时间：2012/10/19 脉冲激光抽运稳定度光频移腔牵引频移\|Abstract 实现了原子钟原理样机的闭环脉冲激光抽运短期稳定度1.2×10~(-12)τ~(-1/2)(τ=100s)。微波分立场共振和自由感应微波辐射或者光吸收检测方案的铷原子钟可以消除光频移有效地减小腔牵引频移从而有利于提高原子钟的稳定度。本文介绍了国家授时中心脉冲激光抽运铷原子钟的研究进展我们获得了POP铷原子钟的原子自感应微波辐射Ramsey信号和光学Ramsey信号微波Ramsey信号的线宽为65Hz左右光学Ramsey信号的线宽为150Hz左右
	DVI interface, optical fiber video transceiver used in LED display system (EI CONFERENCE) 会议论文 OAI收割 2011 IEEE 3rd International Conference on Communication Software and Networks, ICCSN 2011, May 27, 2011 - May 29, 2011, Xi'an, China 作者: Wang R.; Li S. 收藏 \| 浏览/下载：34/0 \| 提交时间：2013/03/25 A professional DVI-Video optical fiber transceiver was designed based on FPGA (Field Programmable Gate Array) in order to meet the need of real-time LED display. The system could be used to transmit a non-loss real-time video source whose resolution was 1024 768 and refresh rate was 60Hz in a single mode optical fiber. The top-down design method was used while programming FPGA. Some module design ideas were discussed including video data acquisition caching framing frame detecting and video reproducing. The required bandwidth of each module was analyzed and calculated in details. Some relevant simulation results were also given. In practical test real-time video display was achieved. And the transmission rate of coded data was up to 2Gbps and the transmission distance could reach 10km. 2011 IEEE.
	A sensitive solid-phase time-resolved fluorescence immunoassay apparatus (EI CONFERENCE) 会议论文 OAI收割 International Symposium on Photoelectronic Detection and Imaging 2009: Laser Sensing and Imaging, June 17, 2009 - June 19, 2009, Beijing, China 作者: Song K.-F.; Li J.-L.; Zhang W.-L.; Wang Y.-L. 收藏 \| 浏览/下载：42/0 \| 提交时间：2013/03/25 In the device a He-Ne laser of flash frequency 1-20 Hz was adopted as exciting light source and three key technical problems have been solved successfully in order to enhance the detecting sensitivity and measuring stability of the device for time-resolved fluorimmunoassays(TRFIA) [1]. The first one is to design optimum exciting optical system so that the exciting light beam excite the sample most effectively. The second one is to have a project spectrum filter which can reduce the affection of the background light to the photomultiplier tube and also ensure influence of the stray light and mixed diffusion light to the sample fluorescence to the least the sample fluorescence through the integrating sphere and come to the grating monochromator The right wavelength will be chosed through changing the angle of incidence of the grating monochromator. The third one is to simulate the principle of sample averaging of BOXCAR averager. In the device SCM was used as primary controller and CPLD was used as timing controller. Through the preparation process signal-to-noise ratio(SNR) will be improved also adjust delay time ampling frequency and sampling number arbitrarily. By testing the sensitivity is 10-12mol/L(substance marked by Eu3+) examination repeat is &le2.5% examination linearity is from 10 -8mol/L to 10-12mol/L correlation coefficient is 99.98%(p&le0.01). The instrument is advanced for ultrasensitive detection of antigen and antibody and solve the tumor genetic variation the virus protein detection. 2009 SPIE.
	Characteristics of ZnMgO-based metal-semiconductor-metal photodetectors (EI CONFERENCE) 会议论文 OAI收割 International Symposium on Photoelectronic Detection and Imaging, ISPDI 2007: Photoelectronic Imaging and Detection, September 9, 2007 - September 12, 2007, Beijing, China 作者: Zhang J.; Li B.; Li B.; Li B.; Zhao Y. 收藏 \| 浏览/下载：26/0 \| 提交时间：2013/03/25 In recent years ZnMgO semiconductor alloys with a direct bandgap tunable between 3.37 eV and 7.8 eV become one of the most suitable materials for the fabrication of ultraviolet detectors. In this paper we have fabricated metal-semiconductor-metal photodetectors on 1-m thick Zn 0.8Mg0.2O films. The interdigital metal electrodes are 500 m long and 5 m wide with an interelectrode spacing 2 m 5 m and 10 m respectively. Zn0.8Mg0.2O films were grown on quartz by ratio frequency magnetron sputtering at 500C. Dark current spectral responsivity and pulse response were carried out for the devices with different finger pitches. All the photodetectors showed the peak responsivity at 330 nm and the ultraviolet-visible rejection ratio (R330 nm/R400 nm) is more than four orders of magnitude at 3 V bias. For the device with 2 m finger pitch the detectivity was calculated as 4.21011 cm Hz 1/2/W at 330 nm. Furthermore the transient response measurement for all devices revealed similar rise time of 10 ns. The 90%-10% fall times are 130 ns 170 ns and 230 ns for the devices with different finger pitches of 2 m 5 m and 10 m respectively..
	An ultra-broadband spatially dispersed regenerative amplifier free from spatial chirp 期刊论文 OAI收割 chin. phys. lett., 2008, 卷号: 25, 期号: 6, 页码: 2048, 2050 Li Chuang; 冷雨欣; Zhang Chun-Mei; 梁晓燕; 李儒新; 徐至展收藏 \| 浏览/下载：1141/74 \| 提交时间：2009/09/18 10-HZ REPETITION RATE TI-SAPPHIRE PULSE AMPLIFICATION LASER-PULSES GENERATION COMPRESSION SYSTEM
	基于USB接口的高精度频率源设计会议论文 OAI收割第十七届全国测控计量仪器仪表学术年会（MCMI'2012）, 中国福建厦门, 2007-10 施韶华; 李孝辉; 黄宁收藏 \| 浏览/下载：25/0 \| 提交时间：2012/10/19 频率源直接数字频率合成通用串行总线 AD9852\|Abstract 直接数字频率合成技术(DDS)具有频率分辨率高相位噪声低频谱好等优点。本文通过对USB协议和DDS技术的研究和分析设计实现了一种采用DDS技术并符合USB总线HID规范的高精度频率源支持即插即用通过主机应用软件对设备进行实时控制可以输出0～120MHz间的任意频率信号频率分辨率可达10-6Hz 相位分辨率为0.02度。
	Highly efficient TW multipass Ti : sapphire laser system 期刊论文 OAI收割 SCIENCE IN CHINA SERIES A-MATHEMATICS PHYSICS ASTRONOMY, 2000, 卷号: 43, 期号: 10, 页码: 1083 Wei, ZY; Zhang, J; Xia, JF; Feng, BH; Zhang, XL; Qiu, Y 收藏 \| 浏览/下载：21/0 \| 提交时间：2013/09/17 REPETITION RATE OPTICAL PULSES GENERATION 10-HZ