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Pseudo-dipole signal removal from WMAP data

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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

Hard X-Ray Modulation Telescope(HXMT) Mission

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空间科学学报 2006年第Z1期26卷 30-41页

作者： li tipei ZHANG Shuangnan LU Fangjun Institute of High Energy Physics Chinese Academy of Sciences Beijing 100049 China Department of Engineering Physics Tsinghua University Department of Physics Tsinghua University Institute of High Energy Physics Chinese Academy of Sciences Beijing 100049 China

The HXMT mission concept consists of a slat-collimated hard X-ray detector assembly sensitive in 20～250 keV with a collection area of about 5000 cm2. Based on the reconstruction technique by direct demodulation developed in recent years, HXMT is mainly devoted to performing a hard X-ray all-sky imaging survey with both high sensitivity and high spatial resolution. It can also be used to make pointed observations of X-ray sources to study their spectroscopic and temporal properties in details. The main detector of HXMT consists of 18 individual cylindrical NaI(T1)/CsI(Na) phoswich modules, each with anarea of 283.5 cm2 and a field of view of 5.7°× 1.1° (FWHM). Its spatial resolution and position accuracy are 5′ and 1′ by using the direct demodulation in 1994, and in 2000 its feasibility and technical demonstration study was selected as a project under the Major State Basic Research Program of China. In October 2005, this project entered the full design phase and was listed as a candidate for the first dedicated astronomy satellite around 2010. We are now also considering secondary low energy instruments for this satellite.

关键词： Space Astronomy, Hard X-ray, Satellite

The flux modulation of INTEGRAL

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Science China(Physics,Mechanics & Astronomy) 2010年第S1期53卷 110-113页

作者： CHEN YuPeng,ZHANG Shu,WANG JianMin,li tipei & QU JinLu Laboratory for Particle Astrophysics,Institute of High Energy Physics,Beijing 100049,China Laboratory for Particle Astrophysics Institute of High Energy Physics Beijing China

We have analyzed International Gamma-Ray Astrophysics Laboratory(INTEGRAL) data corresponding to observations of the high mass X-ray binary(HMXB) V0332+53 during its huge outburst which occurred in 2004-2005,and found that there is a quasi periodic signal with ultra low frequency of roughly 4-5×10-5 Hz in the *** feature is revealed through a series of consistent analyses of imagings and fittings of the energy spectrum for each science window(SCW),and shows up in the corresponding light *** analysis of the power spectrum also provides a hint of a power peak located around 4×10-5 Hz,after subtracting off the linear trend of the light curve,and shows the consistency with the previous analyses.A similar feature shows up in our analysis of the light curve of Crab in hexagonal dithering ***,an instrumental effect on the flux modulation might exist in the INTEGRAL data product of different levels:imaging,spectral fitting and light curve analysis,at least for the observational mode of hexagonal *** an effect is,to our knowledge,not yet available in the current literature.

关键词： X-ray source individual V0332+53

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光子、热力学与膨胀宇宙

科学通报 2015年第34期60卷 3306-3312页

作者：李惕碚吴枚中国科学院高能物理研究所粒子天体物理重点实验室北京100049 清华大学物理系清华大学天体物理中心北京100084 中国科学院大学物理科学学院北京101408

基于宇宙学观测以及含宇宙常数的广义相对论场方程建立的标准宇宙模型,存在着违背物理学基本规律的疑难,提示我们需要仔细审视宇宙动力学的物理基础.例如,同实物退耦后的背景黑体辐射光子数目不再随宇宙膨胀而变化,但宇宙学红移效应导... 详细信息

基于宇宙学观测以及含宇宙常数的广义相对论场方程建立的标准宇宙模型,存在着违背物理学基本规律的疑难,提示我们需要仔细审视宇宙动力学的物理基础.例如,同实物退耦后的背景黑体辐射光子数目不再随宇宙膨胀而变化,但宇宙学红移效应导致辐射温度反比于宇宙尺度下降,则背景辐射总能量也反比于宇宙尺度而不断减少,违背了热力学第一定律,损失的宇宙背景辐射能量到哪里去了?又如,宇宙常数对应的暗能量密度不随时间变化,膨胀宇宙中物质不断被创生,总能量随宇宙膨胀趋于无穷.在宇宙学中坚持能量守恒,需要限制暗物质和暗能量的基本物理性质,其中作为零质量玻色子的光子扮演着重要角色.基于爱因斯坦场方程同时又不放弃能量守恒定律的宇宙学模型,给出了和标准模型完全不同因而可以被观测证实或证伪的演化图景:暗物质同暗能量平衡状态下的匀速膨胀才是宇宙的常态,而减速或加速膨胀只是宇宙介质相变导致的瞬态过程.近期开始出现的高精度宇宙学观测结果对标准模型提出了挑战,而有利于能量守恒宇宙模型的预期.正在进行和计划中的宇宙学观测将最终判定2类模型,并且推动基本物理的发展.

关键词：宇宙背景辐射热力学暗物质暗能量宇宙动力学

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

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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(libration 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 High Energy X-ray telescope (HE) onboard the Insight-HXMT astronomy satellite

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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

Systematic distortion in cosmic microwave background maps

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Science China(Physics,Mechanics & Astronomy) 2009年第5期52卷 804-808页

作者： liU Hao 1,3 &li tipei 1,2 1Key Laboratory of Particle Astrophysics,Institute of High Energy Physics,Chinese Academy of Sciences,Beijing 100049,China 2Center for Astrophysics,Tsinghua University,Beijing 100084,China 3 Graduate University of Chinese Academy of Sciences,Beijing 100049,China Key Laboratory of Particle Astrophysics Institute of High Energy Physics Chinese Academy of Sciences Beijing China Graduate University of Chinese Academy of Sciences Beijing China Center for Astrophysics Tsinghua University Beijing China

To minimize instrumentally the induced systematic errors,cosmic microwave background(CMB)anisotropy experiments measure temperature differences across the sky using pairs of horn antennas, temperature map is recovered from temperature difference obtained in sky survey through a map-making *** inspect and calibrate residual systematic errors in the recovered temperature maps is important as most previous studies of cosmology are based on these *** analyzing pixel-ring coupling and latitude dependence of CMB temperatures,we find notable systematic devia- tion from CMB Gaussianity in released Wilkinson Microwave Anisotropy Probe(WMAP)*** detected deviation cannot be explained by the best-fit LCDM cosmological model at a confidence level above 99%and cannot be ignored for a precision cosmology study.

关键词： cosmology cosmic microwave background methods data analysis

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

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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 1728 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

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天鹅座X-3的高能γ射线

天体物理学报 1989年第3期9卷 286-288页

作者：李惕碚吴枚中国科学院高能物理研究所

对欧洲γ天文卫星COS-B数据的分析迄今未能发现在天鹅座X-3位置上存在着γ射线点源,从1977年6月到1980年6月,COS-B对Cyg-X天区进行了三次观测,各次观测的主要参数见表1,在第22次观测和第36次观测期间,天鹅区X-3大部分时间处于X辐射低态... 详细信息

对欧洲γ天文卫星COS-B数据的分析迄今未能发现在天鹅座X-3位置上存在着γ射线点源,从1977年6月到1980年6月,COS-B对Cyg-X天区进行了三次观测,各次观测的主要参数见表1,在第22次观测和第36次观测期间,天鹅区X-3大部分时间处于X辐射低态,各自只有6天左右处于高态;在第51次观测期间,大部分时间为X辐射高态,只有7天左右处于低态。

关键词：天鹅座 X射线双星 γ射线伽马源