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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：28/0 \| 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).
	Performance of the ALMA Band 10 SIS Receiver Prototype Model 期刊论文 OAI收割 IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY, 2011, 卷号: 21, 期号: 3, 页码: 606-611 作者: Fujii, Yasunori; Kroug, Matthias; Kaneko, Keiko; Gonzalez, Alvaro; Uzawa, Yoshinori 收藏 \| 浏览/下载：30/0 \| 提交时间：2012/08/07 Atacama large millimeter/submillimeter array Band 10 niobium titanium nitride SIS device
	Design of the infrared dual-band athermalized optical system based on HDE (EI CONFERENCE) 会议论文 OAI收割 International Symposium on Photoelectronic Detection and Imaging 2009: Advances in Infrared Imaging and Applications, June 17, 2009 - June 19, 2009, Beijing, China 作者: Zhang L.; Sun Q.; Wang H.; Wang H.; Wang H. 收藏 \| 浏览/下载：99/0 \| 提交时间：2013/03/25 A dual-band infrared optical system adopting an uncooled LW infrared detector and a cooled MW infrared detector is designed and manufactured while in the LW IR band the F/# is 1 and the focal length is 114 mm based on the athermal ability and special diffractive properties of harmonic diffractive elements. The design shows in the MW IR band the F/# is 2 and the focal length is 72 mm for the temperature range -40 70 the MTF value is over 0.5 at 10 lp/mm. Finite element method is applied to the opto-mechanic structure of the system for thermal analysis for the temperature range -40C 70C the MTF value is over 0.4 at 20 lp/mm which confirms the imaging ability of the system in a wide temperature range. 2009 SPIE.
	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：32/0 \| 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.