检索结果-南通市图书馆

New evidence for lack of CMB power on large scales

在线全文

学校读者我要写书评

暂无评论

Science china(physics,Mechanics & Astronomy) 2010年第3期53卷 567-570页

作者： liu hao1.& li tipei1.2,3 1.key laboratory of particle astrophysics, institute of high energy physics, chinese academy of sciences, beijing 1.0049, china 2 Department of physics & Center for astrophysics, Tsinghua University, beijing 100084, china 3 Department of Engineering physics & Center for astrophysics, Tsinghua University, beijing 100084, china key laboratory of particle astrophysics Institute of High Energy Physics Chinese Academy of Sciences Beijing China Department of physics & Center for astrophysics Tsinghua University Beijing China Department of Engineering physics & Center for astrophysics Tsinghua University Beijing China

A digitalized temperature map is recovered from the first light sky survey image published by the Planck team, from which an angular power spectrum of the cosmic microwave background (CMB) is derived. The amplitudes of the low multipoles (low-l) measured from the preliminary Planck power spectrum are significantly lower than those reported by the WMAP team. Possible systematical effects are far from enough to explain the observed low-l differences.

关键词： cosmology cosmic microwave background data analysis

Inconsistency between WMAP data and released map

在线全文

学校读者我要写书评

暂无评论

chinese Science Bulletin 2010年第10期55卷 907-909页

作者： liu hao1.& li tipei1.2,3 1.key laboratory of particle astrophysics,institute of high energy physics,chinese academy of sciences,beijing 1.0049,china 2 Department of physics & Center for astrophysics,Tsinghua University,beijing 100084,china 3 Department of Engineering physics & Center for astrophysics,Tsinghua University,beijing 100084,china key laboratory of particle astrophysics Institute of High Energy Physics Chinese Academy of Sciences Beijing China Department of physics & Center for astrophysics Tsinghua University Beijing China Department of Engineering physics & Center for astrophysics Tsinghua University Beijing China

A remarkable inconsistency between the calibrated differential time-ordered data (TOD) of the Wilkinson Microwave Anisotropy Probe (WMAP) mission,which is the input for map-making,and the cosmic microwave background (CMB) temperature maps published by the WMAP team is revealed,indicating that there must exist a serious problem in the map making routine of the WMAP *** inconsistency is easy to be confirmed without the use of WMAP map-making *** view of the importance of this issue for cosmology study,we invite readers to check it by themselves.

关键词：威尔金森微波各向异性探测器 WMAP 地图制作宇宙微波背景有序数据制作软件 TOD CMB

AP assembled on ultrafine aluminum particle and its application to NEPE propellant

在线全文

学校读者我要写书评

暂无评论

Defence Technology（防务技术） 2024年第6期36卷 20-29页

作者： Huixin Wang Qiang li Hui Ren liangjun Xie Tingting liu Zhihong Chen State key laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing 100081China Inner Mongolia institute of Synthetic Chemicals Hohhot 010010China

Coating modification is an important way to enhance the reactivity of aluminum *** this paper,ammonium perchlorate and aluminum powder were assembled into energetic microunits by liquid deposition *** particles with AP as shell and ultrafine aluminum powder as the core(Al@AP)were *** micromorphology results show that the coated particles are about 5μm,and the coating layer is evenly distributed on the outer surface of aluminum powder,indicating a complete *** energetic microunits were implanted into the nitrate ester plasticizing adhesive system(NEPE)as solid phase *** effect of filler on the rheological properties,safety,mechanical properties,thermal reaction and energy properties of the system was analyzed by comparing with the raw aluminum *** test results show that the rheological properties,mechanical properties and pressure index of NEPE containing system Al@AP meets the requirements of solid propellant *** with Al based propellant,the mechanical sensitivity and thermal sensitivity are decreased,the safety is better,and the explosion heat of the propellant is increased by 7.8%.The engine test shows that the specific impulse is increased by 1.2 ***@AP can improve the energy output and safety of NEPE propellant,and has potential application prospects in high-energy propellants.

关键词： Aluminum powder Coating NEPE propellant energy output Applied research

Pseudo-dipole signal removal from WMAP data

在线全文

学校读者我要写书评

暂无评论

chinese Science Bulletin 2011年第1期56卷 29-33页

作者： liu hao li tipei key laboratory of particle astrophysics Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China Department of physics and Center for astrophysics Tsinghua UniversityBeijing 100084China Department of Engineering physics and Center for astrophysics Tsinghua UniversityBeijing 100084China

We have discovered in our previous work that different observational systematics,*** from antenna pointing directions or an asynchronism between the attitude and science data may generate a pseudo-dipole signal in the full-sky maps of the cosmic microwave background (CMB) anisotropy that have been published by the Wilkinson Microwave Anisotropy Probe (WMAP) *** have found that the antenna sidelobe response to the Doppler signal produces a similar *** this work,independent from the sources,we have uniformly modeled the pseudo-dipole signal and have removed it from the published WMAP7 CMB maps by model *** result demonstrates that the released WMAP CMB quadrupole is almost completely artificial.

关键词：威尔金森微波各向异性探测器数据信号 WMAP 偶极宇宙微波背景辐射天线旁瓣大肠杆菌信号产生

The high energy X-ray telescope (HE) onboard the Insight-HXMT astronomy satellite

在线全文

学校读者我要写书评

暂无评论

Science china(physics,Mechanics & Astronomy) 2020年第4期63卷 20-34页

作者： CongZhan liu YiFei Zhang XuFang li XueFeng Lu Zhi Chang ZhengWei li AiMei Zhang YongJie Jin HuiMing Yu Zhao Zhang MinXue Fu YiBao Chen JianFeng Ji YuPeng Xu JingKang Deng RenCheng Shang GuoQing liu FangJun Lu ShuangNan Zhang YongWei Dong tipei li Mei Wu YanGuo li HuanYu Wang BoBing Wu YongJie Zhang Zhi Zhang Shaolin Xiong Yuan liu Shu Zhang HongWei liu YiJung Yang Fan Zhang key laboratory of particle astrophysics Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China Department of Engineering physics Tsinghua UniversityBeijing 100084China Department of physics Tsinghua UniversityBeijing 100084China University of chinese academy of sciences Beijing 100049China

The Insight-Hard X-ray Modulation Telescope(Insight-HXMT) is a broadband X-ray and γ-ray(1-3000 ke V) astronomy satellite. One of its three main telescopes is the high energy X-ray telescope(HE). The main detector plane of HE comprises 18 Na I(Tl)/Cs I(Na) phoswich detectors, where Na I(Tl) is used as the primary detector to measure ~ 20-250 ke V photons incident from the field of view(FOV) defined by collimators, and Cs I(Na) is used as the active shielding detector to Na I(Tl) by pulse shape discrimination. Additionally, Cs I(Na) is used as an omnidirectional γ-ray monitor. The HE collimators have a diverse FOV,i.e. 1.1°×5.7°(15 units), 5.7°×5.7°(2 units), and blocked(1 unit). Therefore, the combined FOV of HE is approximately5.7°×5.7°. Each HE detector has a diameter of 190 mm resulting in a total geometrical area of approximately 5100 cm2, and the energy resolution is ~15% at 60 ke V. For each recorded X-ray event by HE, the timing accuracy is less than 10 μs and the deadtime is less than 10 μs. HE is used for observing spectra and temporal variability of X-ray sources in the 20-250 ke V band either by pointing observations for known sources or scanning observations to unveil new sources. Additionally, HE is used for monitoring the γ-ray burst in 0.2-3 Me V band. This paper not only presents the design and performance of HE instruments but also reports results of the on-ground calibration experiments.

关键词： X-ray telescope HXMT calibration scintillation detector

The Low energy X-ray telescope (LE) onboard the Insight-HXMT astronomy satellite

在线全文

学校读者我要写书评

暂无评论

Science china(physics,Mechanics & Astronomy) 2020年第4期63卷 49-61页

作者： Yong Chen WeiWei Cui Wei li Juan Wang YuPeng Xu FangJun Lul YuSa Wang TianXiang Chen DaWei Han Wei Hu Yi Zhang Jia Huo YanJi Yang MaoShun li Bo Lu Ziliang Zhang tipei li ShuangNan Zhang Shaolin Xiong Shu Zhang RongFeng Xue XiaoFan Zhao Yue Zhu YuXuan Zhu HongWei liu YiJung Yang Fan Zhang key laboratory of particle astrophysics Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China University of chinese academy of sciences Beijing 100049China Department of physics Tsinghua UniversityBeijing 100084China Department of Education Lu Liang UniversityLuliang 033000China Qian Xuesen laboratory of Space Technology China Academy of Space TechnologyBeijing 100094China College of physics Jilin UniversityChangchun 130023China

The Low energy X-ray telescope(LE) is one of the three main instruments of the Insight-Hard X-ray Modulation Telescope(Insight-HXMT). It is equipped with Swept Charge Device(SCD) sensor arrays with a total geometrical area of 384 cm^2 and an energy band from 0.7 to 13 ke V. In order to evaluate the particle induced X-ray background and the cosmic X-ray background simultaneously, LE adopts collimators to define four types of Field Of Views(FOVs), i.e., 1.6°×6°, 4°×6°, 50°-60°×2°-6 oand the blocked ones which block the X-ray by an aluminum cover. LE is constituted of three detector boxes(LEDs) and an electric control box(LEB) and achieves a good energy resolution of 140 e V@5.9 ke V, an excellent time resolution of 0.98 ms, as well as an extremely low pileup(1%@18000 cts/s). Detailed performance tests and calibration on the ground have been performed,including energy-channel relation, energy response, detection efficiency and time response.

关键词： LE X-ray telescope SCD collimators

The Medium energy X-ray telescope (ME) onboard the Insight-HXMT astronomy satellite

在线全文

学校读者我要写书评

暂无评论

Science china(physics,Mechanics & Astronomy) 2020年第4期63卷 35-48页

作者： XueLei Cao WeiChun Jiang Bin Meng WanChang Zhang Tao Luo Sheng Yang ChunLei Zhang YuDong Gu liang Sun XiaoJing liu JiaWei Yang Xian li Ying Tan ShaoZhen liu YuanYuan Du FangJun Lu YuPeng Xu Ju Guan ShuangNan Zhang HuanYu Wang tipei li ChengMo Zhang XiangYang Wen JinLu Qu liMing Song XiaoBo li MingYu Ge YuPeng Zhou Shaolin Xiong Shu Zhang YongJie Zhang Zehao Cheng Fei Zhang MaoShun li XiaoHua liang Min Gao EnBo Yang XiaoHang liu HongWei liu YiJung Yang Fan Zhang key laboratory of particle astrophysics Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China Department of Engineering physics Tsinghua UniversityBeijing 100084China beijing key laboratory of Space Thermal Control Technology Beijing Institute of Spacecraft System EngineeringBeijing 100094China Department of Modern physics School of Physical SciencesUniversity of Science and Technology of ChinaHefei 230022China School of Physical sciences Guizhou UniversityGuivang 550025China School of Opto-Electronic Information Science and Technology Yantai UniversityYantai 264005China University of chinese academy of sciences Beijing 100049China

The Medium energy X-ray telescope(ME) is one of the three main telescopes on board the Insight hard X-ray modulation telescope(Insight-HXMT) astronomy satellite. ME contains 1.28 pixels of Si-PIN detectors sensitive in 5-30 ke V with a total geometrical area of 952 cm^2. The application specific integrated circuit(ASIC) chip, VA32TA6, is used to achieve low power consumption and low readout noise. The collimators define three kinds of field of views(FOVs) for the telescope, 1°×4°, 4°×4°,and blocked ones. Combination of such FOVs can be used to estimate the in-orbit X-ray and particle background *** energy resolution of ME is ~3 ke V at 17.8 ke V(FWHM) and the time resolution is 255 μs. In this paper, we introduce the design and performance of ME.

关键词： Si-PIN ASIC medium energy X-ray

西湖凹陷中央反转带花港组储层成岩演化南北差异及其影响因素分析

在线全文

学校读者我要写书评

暂无评论

地质论评 2024年第4期70卷 1353-1365页

作者：刘创新高红艳刘彬彬李文俊黄志龙屈童杨易卓夏瑜单理军中海石油(中国)有限公司上海分公司上海200335 油气资源与工程全国重点实验室北京102249 中国石油大学(北京)地球科学学院北京102249

东海盆地西湖凹陷花港组砂岩储层作为西湖凹陷的重要勘探目的层,储层非均质性研究至关重要,笔者等基于储层成岩作用和成岩演化分析,明确中央反转带南北差异,进一步分析其差异成因。研究结果表明,北部地区具有更强的压实作用和溶蚀作用,... 详细信息

东海盆地西湖凹陷花港组砂岩储层作为西湖凹陷的重要勘探目的层,储层非均质性研究至关重要,笔者等基于储层成岩作用和成岩演化分析,明确中央反转带南北差异,进一步分析其差异成因。研究结果表明,北部地区具有更强的压实作用和溶蚀作用,纵向上以3500 m和4000 m为界划分为酸性、酸碱过渡和碱性3个成岩带,经历两期硅质胶结和三期钙质胶结;而南部地区埋深浅、地温低,仅具有两期钙质胶结,纵向上以4000 m为界划分为酸性和碱性两个成岩带;由于北部地区具有更多的岩浆岩母源贡献使得储层抗压实能力较差,遭受压实更强,但烃源岩较强的生烃强度使得储层遭受溶蚀作用更强,因此北部地区花港组储层具有低孔高渗的特征。该研究对优质储层发育研究和甜点预测具有重要意义。

关键词：成岩演化影响因素花港组中央反转带西湖凹陷

Overview to the Hard X-ray Modulation Telescope (Insight-HXMT) Satellite

在线全文

学校读者我要写书评

暂无评论

Science china(physics,Mechanics & Astronomy) 2020年第4期63卷 2-19页

作者： Shuang-Nan Zhang tipei li FangJun Lu liMing Song YuPeng X u CongZhan liu Yong Chen XueLei Cao QingCui Bu Zhi Chang Gang Chen li Chen TianXiang Chen YiBao Chen YuPeng Chen Wei Cui WeiWei Cui JingKang Deng YongWei Dong Yuan Yuan Du MinXue Fu GuanHua Gao He Gao Min Gao MingYu Ge YuDong Gu Ju Guan Can Gungor ChengCheng Guo DaWei Han Wei Hu Yue Huang Jia Huo ShuMei Jia LuHua Jiang WeiChun Jiang Jing Jin YongJie Jin Bing li ChengKui li Gang li MaoShun li Wei li Xian li XiaoBo li XuFang li YanGuo li ZiJian li ZhengWei li XiaoHua liang JinYuan liao GuoQing liu HongWei liu ShaoZhen liu XiaoJing liu Yuan liu YiNong liu Bo Lu XueFeng Lu Tao Luo Xiang Ma Bin Meng Yi Nang JianYin Nie Ge Ou JinLu Qu Na Sai RenCheng Shang GuoHong Shen liang Sun Ying Tan lian Tao Youli Tuo Chen Wang ChunQin Wang GuoFeng Wang HuanYu Wang Juan Wang WenShuai Wang YuSa Wang XiangYang Wen BaiYang Wu BoBing Wu Mei Wu GuangCheng Xiao Shaolin Xiong linli Yan JiaWei Yang Sheng Yang YanJi Yang QiBin Yi Bin Yuan AiMei Zhang ChunLei Zhang ChengMo Zhang Fan Zhang HongMei Zhang Juan Zhang Qiang Zhang ShenYi Zhangs Shu Zhang Tong Zhang WanChang Zhang Wei Zhang WenZhao Zhang Yi Zhang YiFei Zhang YongJie Zhang Yue Zhang Zhao Zhang Zhi Zhang Ziliang Zhang HaiSheng Zhao XiaoFan Zhao ShiJie Zheng JianFeng Zhou YuXuan Zhu Yue Zhu Renlin Zhuang key laboratory of particle astrophysics Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China University of chinese academy of sciences Beijing 100049China Department of Astronomy Tsinghua UniversityBeijing 100084China Department of physics Tsinghua UniversityBeijing 100084China Department of Astronomy Beijing Normal UniversityBeijing 100088China Department of Engineering physics Tsinghua UniversityBeijing 100084China National Astronomical Observatories Chinese Academy of SciencesBeijing 100101China National Space Science Center Chinese Academy of SciencesBeijing 100190China

As china’s first X-ray astronomical satellite, the Hard X-ray Modulation Telescope (HXMT), which was dubbed as Insight-HXMT after the launch on June 15, 2017, is a wide-band(1.250 ke V) slat-collimator-based X-ray astronomy satellite with the capability of all-sky monitoring in 0.2-3 Me V. It was designed to perform pointing, scanning and gamma-ray burst(GRB)observations and, based on the Direct Demodulation Method (DDM), the image of the scanned sky region can be *** we give an overview of the mission and its progresses, including payload, core sciences, ground calibration/facility, ground segment, data archive, software, in-orbit performance, calibration, background model, observations and some preliminary results.

关键词： X-and γ-ray telescopes and instrumentation neutron stars black holes X-ray binaries γ-ray bursts