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	VLBI astrometry on the white dwarf pulsar AR Scorpii 期刊论文 OAI收割 Monthly Notices of the Royal Astronomical Society, 2023, 卷号: 520, 期号: 2, 页码: 2942-2951 作者: Jiang, Pengfei; Cui, Lang; Yang, Jun; Zhang, Bo; Xu, Shuangjing \| 收藏 \| 浏览/下载：1/0 \| 提交时间：2024/06/23 techniques: high angular resolution parallaxes pulsars: individual: AR Sco white dwarfs radio continuum: stars x-ray optical observations emission geometry radio-emission black-hole binary mass sco kinematics herculis Astronomy & Astrophysics
	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：26/0 \| 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).
	Observationally based analysis of land-atmosphere coupling 期刊论文 OAI收割 Earth System Dynamics, 2016, 卷号: 7, 期号: 1, 页码: 251-266 作者: Catalano, Franco; Alessandri, Andrea; De Felice, Matteo; Zhu, Zaichun; Myneni, Ranga B. 收藏 \| 浏览/下载：31/0 \| 提交时间：2017/04/24 SINGLE-SCATTERING PROPERTIES MULTIDIRECTIONAL POLARIZATION MEASUREMENTS INHOMOGENEOUS HEXAGONAL MONOCRYSTALS DISCRETE-DIPOLE APPROXIMATION ADEOS-POLDER MEASUREMENTS BOUNDARY-ELEMENT METHOD IN-SITU OBSERVATIONS TIME-DOMAIN METHOD LIGHT-SCATTERING OPTICAL-PROPERTIES
	Black carbon radiative forcing at TOA decreased during aging 期刊论文 OAI收割 Scientific Reports, 2016, 卷号: 6 作者: Wu, Yu; Cheng, Tianhai; Zheng, Lijuan; Chen, Hao 收藏 \| 浏览/下载：35/0 \| 提交时间：2017/04/24 LAND-USE REGRESSION AEROSOL OPTICAL DEPTH MIXING-LAYER HEIGHT AIR-POLLUTION MATTER CONCENTRATIONS SATELLITE-OBSERVATIONS LEVEL PM2.5 RETRIEVAL CHINA ALGORITHM
	Coastal zone classification with fully polarimetric SAR imagery 期刊论文 OAI收割 IEEE Geoscience and Remote Sensing Letters, 2016, 卷号: 13, 期号: 11, 页码: 1616-1620 作者: Gou, Shuiping; Li, Xiaofeng; Yang, Xiaofeng 收藏 \| 浏览/下载：29/0 \| 提交时间：2017/04/24 SKY RADIANCE MEASUREMENTS OPTICAL-PROPERTIES PHOTOPOLARIMETRIC MEASUREMENTS BIDIRECTIONAL REFLECTANCE SATELLITE-OBSERVATIONS INVERSION ALGORITHM INFORMATION-CONTENT SOLAR IRRADIANCE POLARIZATION SUN
	In situ optical observations of keyhole dynamics during laser drilling 期刊论文 OAI收割 APPLIED PHYSICS LETTERS, 2013, 卷号: 103, 期号: 19, 页码: 194102/1-194102/4 作者: Chen M(陈猛); Wang YR(王育人); Yu G(虞钢); Lan D(蓝鼎); Zheng ZY(郑中玉) 收藏 \| 浏览/下载：35/0 \| 提交时间：2014/01/17 High speed photography Drilling assembly Drilling process Dynamics coupling Hole expansions In-situ optical observations Physical process Thin sandwich structures Unified process
	Baseline continental aerosol over the central Tibetan plateau and a case study of aerosol transport from South Asia 期刊论文 OAI收割 ATMOSPHERIC ENVIRONMENT, 2011, 卷号: 45, 期号: 39, 页码: 7370-7378 Xia XG (Xia Xiangao); Zong XM (Zong Xumei); Cong ZY (丛志远); Chen HB (Chen Hongbin); Kang SC (康世昌); Wang PC (Wang Pucai) 收藏 \| 浏览/下载：32/0 \| 提交时间：2012/05/08 LIDAR OBSERVATIONS OPTICAL DEPTH NAM CO CLIMATE AERONET CLOUDS SEASON
	Multi-color optical variability of the TeV blazar Mrk 501 in the low-state 期刊论文 OAI收割 NEW ASTRONOMY, 2008, 卷号: 13, 期号: 6, 页码: 375-384 作者: A. C. Gupta; Deng WG(邓文国); Joshi, UC; Bai JM(白金明); Lee, MG 收藏 \| 浏览/下载：24/0 \| 提交时间：2016/04/12 optical observations - BL lacertae objects individual (Mrk 501)
	Research on the support structure of the primary mirror of large-aperture telescope (EI CONFERENCE) 会议论文 OAI收割 3rd International Symposium on Advanced Optical Manufacturing and Testing Technologies, AOMATT 2007: Large Mirrors and Telescopes, July 8, 2007 - July 12, 2007, Chengdu, China Yang W.; Jingxu Z. 收藏 \| 浏览/下载：32/0 \| 提交时间：2013/03/25 Large-aperture telescope can be used in surveying battlefield researching landform searching object real-time monitoring imaging detecting and identifying spatial targets and so on. A large-aperture telescope for achieving high resolution power is designed to monitor spatial target and image in real time. Real-time monitoring plays an important role in military conflicts. The orbit parameter of object quantity geometrical shape parameter and so on can be obtained by detect spatial target. With the development of optical technology people require larger aperture in optics-electronic (OE) system. By increasing optical aperture the ability of collecting light and resolution power in the system can be enhanced. But the support structure of the primary mirror of large-aperture telescope will be a very difficult problem. With the increase of primary mirror aperture the weight of the primary mirror will become larger than before. The root mean square (rms) of the primary mirror is affected by many factors such as deadweight deformation of heat environment and so on. Due to the primary mirror of telescope is an important component of telescope system. By reducing the weight of primary mirror precision of the system is ensured. During the designing phase one can consider the supporting project of the primary mirror synthetically and analyze it roundly according to technical requirement of optical system and the effect factors. The final structural design can be reasonable. In an astronomical telescope the surface of reflector is an important part for collecting dark radiation of celestial bodies. Its surface shape will have an effect on collecting efficiency of telescope radiant energy directly. So the rms must be very high. Optical system of large aperture small wavelength and small focus can receive maximal light intensity. For ground-based optical astronomical telescope the design proposed in the paper can satisfy the requirement of the possible minimum atmosphere seeing at astronomical observatory site and exert the use efficiency of the telescope adequately. So the accuracy of the traditional surface of reflector can assure that 90% of all the light energy can be focused on within the angle diameter range of the minimum atmosphere seeing then 100% of light energy should be focused on the angle diameter range of minimum atmosphere seeing. Because the rms of mirror is very high precise surface machining and accurate the support of mirror are very important tasks during designing and manufacturing the telescope. In the paper various support techniques of a large-aperture telescope primary mirror are discussed and a 3.5 meter telescope system at the Starfire Optical Range (SOR) overviewed simply which was operated by the Directed Energy Directorate of the Air Force Research Laboratory Kirtland AFB NM USA from the ground-based O-E system for the observations of spatial target. We also analyze Theoretical elastic deformation of the Steward Observatory 2.3 meter mirror is analyzed.