Disc–corona energetics in the very high state of Galactic black holes     

Chris Done  Aya Kubota 《Monthly notices of the Royal Astronomical Society》2006,371(3):1216-1230

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Simulating cosmic reionization at large scales – II. The 21-cm emission features and statistical signals     

Garrelt Mellema †  Ilian T. Iliev  Ue-Li Pen  Paul R. Shapiro 《Monthly notices of the Royal Astronomical Society》2006,372(2):679-692

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High energy radiation from the center of the local supercluster     

H. C. Arp  J. V. Narlikar  H. -D. Radecke 《Astroparticle Physics》1997,6(3-4):387-394

Evidence in X-rays, gamma rays and ultra high energy cosmic rays (UHCR) suggests the existence of active centers in extragalactic space which eject high energy particles and quanta. A concentration of these highest energy sources in the direction of the Local Supercluster indicates that the brightest apparent magnitude AGN's such as 3C274 (M87), 3C273, 3C279 and Markarian 421 are the only candidate sources for this radiation. A theoretical model of mass creation in the Local Supercluster based on a Machian theory of gravitation is described as a possible mechanism for production of the high energy while at the same time allowing the AGN's to be at the relatively close distance of the Supercluster. The fact that infrared photons fill intergalactic space limits the distance to the UHCR sources at a little over twice the distance to the center of the Local Supercluster strongly localizing the highest energy radiation to this relatively close distance.  相似文献   

Anisotropic inverse Compton emission in the radio galaxy 3C 265   总被引：1，自引：0，他引：1  

M. Bondi  G. Brunetti  A. Comastri  G. Setti 《Monthly notices of the Royal Astronomical Society》2004,354(3):L43-L47

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The polarization of afterglow emission reveals γ-ray bursts jet structure     

Elena M. Rossi  Davide Lazzati  Jay D. Salmonson  Gabriele Ghisellini 《Monthly notices of the Royal Astronomical Society》2004,354(1):86-100

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Luminous hot accretion flows: the origin of X-ray emission from Seyfert galaxies and black hole binaries     

Feng Yuan  Andrzej A. Zdziarski 《Monthly notices of the Royal Astronomical Society》2004,354(3):953-960

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关于CAS FGOALS-f3-L模式中青藏高原地表温度偏差的归因分析          下载免费PDF全文

Yao Wu  Yimin Liu  Jiandong Li  Qing Bao  Bian He  Lei Wang  Xiaocong Wang  Jinxiao Li 《大气和海洋科学快报》2021,14(1):69-75

中国科学院全球海洋-大气-陆地耦合模式(FGOALS-f3-L)参加了耦合模式比较计划的第六阶段(CMIP6)试验,但是其对关键气候敏感地区青藏高原的地表温度的再现能力还不清楚.这项研究用再分析资料CFSR评估了FGOALS-f3-L模式对青藏高原地表温度的再现能力.结果表明,FGOALS-f3-L可以合理模拟整个高原上年平均地表温度的空间分布,但低估了整个高原上年平均地表温度.模拟的地表温度在整个高原上冬春季表现为冷偏差,夏秋季表现为暖偏差.基于地表能量平衡方程的进一步定量分析表明,地表反照率反馈(SAF)项极大地贡献了高原西部年平均,冬春季平均地表温度的冷偏差,而对高原东部是暖偏差贡献.与SAF项相比,地表感热项对地表温度偏差的贡献几乎相反,这大大抵消了SAF项引起的偏差.云辐射强迫项对高原东部的年平均和季节平均弱冷偏差有很大贡献.与高估的水蒸气含量有关的长波辐射项造成了夏秋季整个高原上大部分的暖偏差.该研究表明,提高FGOALS-f3-L中的陆面和云过程对降低高原上地表温度偏差至关重要.  相似文献   

The compressibility of Fe- and Al-bearing phase D to 30 GPa     

Konstantin D. Litasov  Eiji Ohtani  Akio Suzuki  Kenichi Funakoshi 《Physics and Chemistry of Minerals》2007,34(3):159-167

High-pressure in situ X-ray diffraction experiment of Fe- and Al-bearing phase D (Mg_0.89Fe_0.14Al_0.25Si_1.56H_2.93O₆) has been carried out to 30.5 GPa at room temperature using multianvil apparatus. Fitting a third-order Birch–Murnaghan equation of state to the P–V data yields values of V ₀ = 86.10 ± 0.05 ų; K ₀ = 136.5 ± 3.3 GPa and K′ = 6.32 ± 0.30. If K′ is fixed at 4.0 K ₀ = 157.0 ± 0.7 GPa, which is 6% smaller than Fe–Al free phase D reported previously. Analysis of axial compressibilities reveals that the c-axis is almost twice as compressible (K _c  = 93.6 ± 1.1 GPa) as the a-axis (K _a  = 173.8 ± 2.2 GPa). Above 25 GPa the c/a ratio becomes pressure independent. No compressibility anomalies related to the structural transitions of H-atoms were observed in the pressure range to 30 GPa. The density reduction of hydrated subducting slab would be significant if the modal amount of phase D exceeds 10%.  相似文献   

月球目标监测风云二号静止气象卫星可见光辐射响应变化     

陈林  张鹏  吴荣华  胡秀清  张璐 《遥感学报》2018,22(2):211-219

月球的光度具有纪年级的稳定性,其辐照度可作为可见—近红外光谱辐射基准,基于此的月球辐射定标方法有望成为辐射定标的新方法之一。本文介绍一种利用月球目标作为稳定辐射定标源,结合月球辐照度模型,跟踪风云二号静止气象卫星遥感仪器可见光通道辐射响应变化的方法。通过轨道预报遴选出风云二号E星(FY-2E)的扫描辐射计2010年1月—2014年10月的对月观测数据,经过月球图像提取和筛选、月球照度模型计算、卫星观测月球照度模型计算、星—月—日距离校正等环节处理后,获取了FY-2E扫描辐射计可见光通道的辐射响应变化,并且与深对流云辐射定标方法进行了对比验证。主要结果:(1)利用月球辐射作为基准可有效监测遥感仪器可见光通道的辐射响应变化情况,通过线性回归分析发现FY-2E可见光通道的辐射响应总衰减率是9.2%,年衰减率为1.96%,95%置信区间的不确定度和稳定性指标分别为±0.79%和2.66,其结果与基于深对流云目标监测的仪器辐射响应结果相近;(2)FY-2E可见光通道较低的量化等级(6 bit)、杂散光影响等因素对利用月球进行辐射响应定标和跟踪监测有一定的影响;(3)FY-2E辐射响应除了衰减趋势,还存在周期性震荡的特点。基于月球目标的辐射定标方法能够有效监测卫星的辐射响应衰减,可作为星载遥感仪器辐射响应定标和检验的一种可靠手段,特别是针对卫星全生命周期的历史数据再定标,从而提高辐射定标精度。  相似文献   

Analysis of Cloud Scale Error of Low Resolution Satellite Based on GF-4 and Its Influence on Downward Radiation Calculation     

Chuanxiang Yi  Xiaozhou Xin  Jichao Hu  Hailong Zhang  Xiaojun Li  Wei Gong 《地球科学进展》2018,33(4):425-434

In order to study the scale error of low resolution meteorological satellite cloud detection and its impact on the calculation of downlink radiation, cloud detection using high resolution stationary satellite GF-4 data and error analysis were carried out. Firstly, the cloud detection of GF-4 data is carried out by using visible channel threshold method and time series method, and the error of cloud detection results of Himawari-8 and FY-2 (FY-2G, FY-2E) is analyzed based on the results of GF-4 cloud detection.In the study area, FY-2G, FY-2E and Himawari-8 cloud images could distinguish the clouds and clear sky. The main reason for the error was the scale effect produced by different spatial resolution satellites(the differences caused by cloud detection algorithms are not discussed here).Most of the errors occurred in the areas of thin clouds and broken clouds.High resolution data could detect broken clouds, while low resolution data lead to false and missed detection. On this basis, the error of remote sensing calculation of short wave radiation was analyzed,and it was found that the error of the actual cloud amount in the pixel would bring significant error to the estimation of the downward radiation.The relative error of the instantaneous downward radiation in the selected test area was -173.52%, and the maximum relative error of shortwave radiation was -20.20%.The results show that the high resolution stationary satellite data can significantly improve the estimation accuracy of the downlink shortwave radiation in the regions with more broken clouds.  相似文献