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	Comparison of simulated backgrounds with in-orbit observations for HE, ME, and LE onboard Insight-HXMT 期刊论文 OAI收割 Astrophysics and Space Science, 2020, 卷号: 365, 页码: 158 作者: HXMT \| 收藏 \| 浏览/下载：51/0 \| 提交时间：2022/02/08 Insight-HXMT Geant4 simulation Background observation Astrophysics - Instrumentation and Methods for Astrophysics Abstract: Insight-HXMT, the first X-ray astronomical satellite in China, aims to reveal new sources in the Galaxy and to study fundamental physics of X-ray binaries from 1 to 250 keV. It has three collimated telescopes, the High Energy X-ray telescope (HE), the Medium Energy X-ray telescope (ME), and the Low Energy X-ray telescope (LE). Before the launch, in-orbit backgrounds of these three telescopes had been estimated through Geant4 simulation, in order to investigate the instrument performance and the achievement of scientific goals. In this work, these simulated backgrounds are compared with in-orbit observations. Good agreements are shown for all three telescopes. For HE, (1) the deviation of the simulated background rate after two years of operation in space is 5 % from the observation (2) the total background spectrum and the relative abundance of the 67 keV line show long-term increases both in simulations and observations. For ME, (1) the deviation of simulated background rate is within 15 % from the observation, and (2) there are no obvious long-term increase features in the background spectra of simulations and observations. For LE, the background level given by simulations is also consistent with observations. The consistencies of these comparisons validate that the Insight-HXMT mass model, i.e., space environment components and models adopted, physics processes selected, and detector constructions built, is reasonable. However, the line features at 7.5 and 8.0 keV, which are obvious in the observed spectra of LE, are not evident in simulations. This might result from uncertainties in the LE constructions.
	Rearrangeable nonblocking 88 matrix optical switches based on extended banyan network (EI CONFERENCE) 会议论文 OAI收割作者: Zhang Y. 收藏 \| 浏览/下载：29/0 \| 提交时间：2013/03/25 Based on the CROSSBAR network (CN) and the BANYAN network (BN) 8 matrix optical switch two new rearrangeable nonblocking constructions of extended BANYAN network (EBN) are proposed for implementing 88 optical matrix switch. The interconnection characteristics of these two types of rearrangeable nonblocking EBN were studied optical insertion loss of 4.6 dB and the logic program for driving switching units was provided. The calculated insertion loss was 3.3 dB for 88 optical matrix switch. Silica waveguide 88 matrix optical switch was designed and fabricated according to the calculated results. The silica waveguide propagation loss of 0.1 dB/cm and waveguide-fiber coupling loss of 0.5dB/point were measured. With the fabricated 87times cross-talk of -38 dB polarization dependent loss of 0.4 dB averaged switching power of 1.6 W and switching time of 1 ms were achieved. A basic agreement between experimental results and theoretical calculated values was achieved.
	Rearrangeable nonblocking 88 matrix optical switch based on silica waveguides and extended banyan network (EI CONFERENCE) 会议论文 OAI收割 Science and Technology of Dielectrics for Active and Passive Photonic Devices - 210th Electrochemical Society Meeting, October 29, 2006 - November 3, 2006, Cancun, Mexico 作者: Zhang Y. 收藏 \| 浏览/下载：30/0 \| 提交时间：2013/03/25 Based on the CROSSBAR network (CN) and the BANYAN network (BN) two new rearrangeable nonblocking constructions of extended BANYAN network (EBN) were proposed for implementing 88 optical matrix switch. The interconnection characteristics of these two types of rearrangeable nonblocking EBN were studied and the driver logic program of switching units was provided. The calculated insertion loss is 3.3 dB for 88 optical matrix switch. Silica waveguide 88 matrix optical switch was designed and fabricated according to the calculated results. The silica waveguide propagation loss of 0.1 dB/cm and waveguide-fiber coupling loss of 0.5dB/point were measured out. With the fabricated 88 matrix optical switch optical insertion loss of 4.6 dB cross-talk of -38 dB polarization dependent loss of 0.4 dB averaged switching power of 1.6 W and switching time of 1 ms were achieved. A basic agreement between experimental results and theoretical calculated values was achieved. copyright The Electrochemical Society.
	The Role of Tillage in Soil Redistibution Within Terraced Fields on The Loess Plateau, China: An Investigation Using Cesiun-137 会议论文 OAI收割 Warsaw, 1993 作者: Quine T.A.; Walling D.E.; Zhang X. \| 收藏 \| 浏览/下载：15/0 \| 提交时间：2018/11/08 Building projects Debris flows Experimental conditions Geometric similarity Laboratory experiments New constructions Parabolic distribution Plane configurations