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Inconsistency between WMAP data and released map

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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 100049,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

Temporal study of GRS 1915+105 with rms-flux relation:The importance of magnetic activities in the corona

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Science China(Physics,Mechanics & Astronomy) 2010年第S1期53卷 120-124页

作者： HAN Dong1,ZHANG ShuangNan2 & SONG LiMing2 1 Department of Engineering Physics & Center for astrophysics,Tsinghua University,Beijing 100084,China 2 key laboratory of particle astrophysics,Institute of High Energy Physics,Chinese Academy of Sciences,Beijing 100049,China Department of Engineering Physics & Center for astrophysics Tsinghua University Beijing China key laboratory of particle astrophysics Institute of High Energy Physics Chinese Academy of Sciences Beijing China

The rms-flux relations for some observations of GRS 1915+105 are *** rms-flux relations of the light curves in only one state,state C or state A,can be described by the simple non-linear model provided Zhang;we thus interpret that such a linear relation reflects the relative importance of magnetic instability for X-ray emission in the corona of the system,compared to the thermal viscous instability for the X-ray emission in the accretion *** rms-flux relations for state B are very scattered,possibly because of the dominance of thermal viscous instability for the X-ray emission in the accretion *** complex rms-flux relations for the observations of transitions between two or three states are caused by the combination of the different rms-flux relations of these *** underlying physical processes are the combination of magnetic topology in the corona and thermal viscous instability in the accretion disk.

关键词： rms-flux relation data analysis GRS 1915+105 magnetic instability

Development of the super high angular resolution principle for X-ray imaging

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Research in Astronomy and astrophysics 2011年第1期11卷 119-124页

作者： Chen Zhang Shuang-Nan Zhang National Astronomical Observatories Chinese Academy of Sciences Beijing 100012 China Department of Physics ＆ Center for astrophysics Tsinghua University Beijing 100084 China key laboratory of particle astrophysics Institute of High Energy Physics Chinese Academy ofSciences Beijing 100049 China

Development of the Super High Angular Resolution Principle （SHARP） for coded-mask X-ray imaging is presented. We prove that SHARP can be considered as a generalized coded mask imaging method with a coding pattern comprised of diffraction-interference fringes in the mask pattern. The angular resolution of SHARP can be improved by detecting the fringes more precisely than the mask＇s element size, i.e. by using a detector with a pixel size smaller than the mask＇s element size. The proposed mission SHARP-X for solar X-ray observations is also briefly discussed.

关键词： instrumentation: high angularresolution-- techniques: image processing-- telescopes

GRB 190530A:From Precursor,Prompt Emission to Afterglow all Originated from Synchrotron Radiation

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Research in Astronomy and astrophysics 2022年第6期22卷 22-32页

作者： Hui-Ya Liu Xiang-Gao Wang Li-Ping Xin Zi-Min Zhou Liang-Jun Chen Bing Li Yuan-Gui Yang Qi Luo Cheng-Kui Li Shao-Lin Xiong Ling-Jun Wang Xu-Hui Han Li-Ming Song Jian-Yan Wei En-Wei Liang Shuang-Nan Zhang Guangxi key laboratory for Relativistic astrophysics Department of PhysicsGuangxi UniversityNanning 530004China GXU-NAOC Center for astrophysics and Space Sciences Nanning 530004China CAS key laboratory of Space Astronomy and Technology National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100101China key laboratory of particle astrophysics Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China School of Physics and Electronic Information Huaibei Normal UniversityHuaibei 235000China

GRB 190530A was jointly observed by the High Energy X-ray Telescope of the Hard X-ray Modulation Telescope(Insight-HXMT/HE)and the Ground-Based Wide-Angle Camera network(GWAC-N)with the extremely large field of *** triggered by Insight-HXMT/HE and Fermi/GBM,we observed the optical emission of GRB 190530A,using the 30 cm telescope of GWAC(GWAC-F30)to search and locate its *** observation of the late afterglow of GRB 190530A was made with the 2.16 m telescope at Xinglong *** this paper,we make a detailed exploration of the origin of GRB *** the prompt emission,a“double-tracking”pattern is presented both for the low-energy spectral indexαand the peak energy Epin the Band function with Insight-HXMT/HE and Fermi/GBM data;the results of GRB 190530A are consistent with the Amati and Yonetoku correlations;the spectral lag(τ)versus energy(E)can be estimated withτ=-3.0±0.06+(0.17±0.03)*** synchrotron radiation can account for the origin of GRB190530A prompt emission ***αand Epof the precursor are essentially the same as that of the main prompt emission,implying that they have the same *** the afterglow,it can be described with the external forward shock model in ISM circumburst *** summary,from precursor,prompt emission to afterglow of GRB 190530A all originated from synchrotron radiation.

关键词： (stars)gamma-ray burst:individual(GRB 190530A)-(stars)gamma-ray burst general-virtual observatory tools

Design of hadronic calorimeter for DarkSHINE experiment

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Nuclear Science and Techniques 2024年第9期35卷 155-167页

作者： Zhen Wang Rui Yuan Han-Qing Liu Jing Chen Xiang Chen Kim Siang Khaw Liang Li Shu Li Kun Liu Qi-Bin Liu Si-Yuan Song Tong Sun Xiao-Long Wang Yu-Feng Wang Hai-Jun Yang Jun-Hua Zhang Yu-Lei Zhang Zhi-Yu Zhao Chun-Xiang Zhu Xu-Liang Zhu Yi-Fan Zhu Tsung-Dao Lee Institute Shanghai Jiao Tong University1 Lisuo RoadShanghai 201210China Institute of Nuclear and particle Physics School of Physics and Astronomy800 Dongchuan RoadShanghai 200240China key laboratory for particle astrophysics and Cosmology(MOE) Shanghai Key Laboratory for Particle Physics and Cosmology(SKLPPC)Shanghai Jiao Tong University800 Dongchuan RoadShanghai 200240China key laboratory of Nuclear Physics and Ion-beam Application(MOE) Fudan UniversityShanghai 200443China Institute of Modern Physics Fudan UniversityShanghai 200443China

The sensitivity of the dark photon search through invisible decay final states in low-background experiments relies sig-nificantly on the neutron and muon veto efficiencies,which depend on the amount of material used and the design of the detector *** paper presents the optimized design of the hadronic calorimeter(HCAL)used in the DarkSHINE experiment,which is studied using a GEANT4-based simulation *** geometry is optimized by comparing a traditional design with uniform absorbers to one that uses different thicknesses at different locations on the detector,which enhances the efficiency of vetoing low-energy neutrons at the sub-GeV *** overall size and total amount of material used in the HCAL are optimized to be lower,owing to the load and budget requirements,whereas the overall performance is studied to satisfy the physical objectives.

关键词： Hadronic calorimeter GEANT4 simulation Neutron background Scintillation detector Dark photon

Design of a compact C-band high brightness photoinjector for an ultra-fast electron diffraction

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Chinese Science Bulletin 2013年第36期58卷 4577-4581页

作者： LIU XiaoHan TANG ChuanXiang QIAN HouJun CHEN HuaiBi HUANG WenHui key laboratory of particle & Radiation Imaging Ministry of Education Department of Engineering Physics Tsinghua University

A compact C-band high brightness photoinjector for ultra-fast electron diffraction(UED)is under development at Tsinghua *** C-band photoinjector,operating at 5.172 GHz,uses a 1.45-cell C-band RF gun as the electron *** design of the RF gun has addressed the physics,beam dynamics and mechanical aspects,and based on these design studies,a prototype has been *** order to obtain optimized performance for the UED,beam dynamics simulation has been carried out using the particle tracking code Astra for the photoinjector consisting of an alternative multi-cell RF gun design and a C-band compressor *** beam dynamics parameters that are optimized include the bunch length,peak current,horizontal emittance,and position of the minimum bunch length.

关键词：电子衍射 C波段高亮度紧凑型设计微波电子枪束流动力学束团长度

Total decay width of H → gg using the infinite-order scale-setting approach based on intrinsic conformality

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Chinese Physics C 2022年第12期46卷 172-178页

作者： Chu-Tian Gao Xing-Gang Wu Xu-Dong Huang Jun Zeng Department of Physics Chongqing Key Laboratory for Strongly Coupled PhysicsChongqing UniversityChongqing 401331China Institute of High Energy Physics CASBeijing 100049China School of Physics University of Chinese Academy of SciencesBeijing 100049China INPAC Key Laboratory for Particle Astrophysics and Cosmology(MOE)Shanghai Key Laboratory for Particle Physics and CosmologySchool of Physics and AstronomyShanghai Jiao Tong UniversityShanghai 200240China

We conducted a detailed study on the properties of the total decay width of the Higgs decay channel H→gg up toα_(s)^(6)-order QCD corrections by using the newly suggested infinite-order scale-setting approach,which is based on both the principle of maximum conformality and intrinsic *** approach is called PMC_(∞) By using the PMC_(∞)approach,we observed that the conventional renormalization scale ambiguity in perturbative QCD calculation is eliminated,and the residual scale dependence due to unknown higher-order terms can also be highly *** then obtained an accurate perturbative QCD prediction on the total decay width,e.g.,Г(H→gg)|PMC_(∞)=336.42_(-6.92)^(+7.01)keV,where the errors are squared averages of those from all the mentioned error sources.

关键词： pQCD renormalization Higgs decay

A curve-based material recognition method in MeV dual-energy X-ray imaging system

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Nuclear Science and Techniques 2016年第1期27卷 13-20页

作者： Zhi-Qiang Chen Tiao Zhao Liang Li Department of Engineering Physics Tsinghua University key laboratory of particle and Radiation Imaging (TsinghuaUniversity) Ministry of Education

High-energy dual-energy X-ray digital radiography imaging is mainly used in the material recognition of cargo inspection. We introduce the development history and principle of the technology and describe the data process flow of our system. The system corrects original data to get a dual-energy transparence image. Material categories of all points in the image are identified by the classification curve,which is related to the X-ray energy spectrum. For the calibration of classification curve, our strategy involves a basic curve calibration and a real-time correction devoted to enhancing the classification accuracy. Image segmentation and denoising methods are applied to smooth the image. The image contains more information after colorization. Some results show that our methods achieve the desired effect.

关键词： X射线成像系统校准曲线材料识别识别方法数据处理流程透明图像分类精度实时校正

Physics design of collimators to reduce lost particle background at the CEPC

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Chinese Physics C 2016年第11期40卷 166-173页

作者：岳腾修青磊王毅伟段哲秦庆 key laboratory of particle Acceleration Physics and Technology Institute of High Energy PhysicsCAS

At the CEPC （Circular Electron Positron Collider）, which is proposed by the Chinese high energy physics community, the dominant background comes from radiative Bhabha scattering and the beamstrahlung effect according to preliminary research. Therefore, it is necessary to incorporate a collimator system to intercept particles that may be lost near the interaction region （IR）. In this paper, we introduce some limitations in choosing the position and width of the collimators. A certain parameter range is determined which is confined by the β function and the width of the collimators. A suitable choice of the half width is made by exploring this parameter range. A simulation of the particle loss rate in the IR and the hit density in the vertex detector with and without the collimators shows that the set of parameters of the collimators we designed is appropriate and effective.

关键词： CEPC lost particle background collimator