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New evidence for lack of CMB power on large scales

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

作者： liu hao1 & {2. {{3.,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 {2. {3. Institute of High Energy Physics Chinese Academy of Sciences Department of physics & Center for astrophysics Tsinghua University Department of Engineering physics & Center for astrophysics Tsinghua University

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

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

作者： liu hao1 & {2. {{3.,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 {2. {3. 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

Design and prototyping of the readout electronics for the transition radiation detector in the high energy cosmic radiation detection facility

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Nuclear Science and Techniques 2024年第4期35卷 189-199页

作者： Jie-Yu Zhu Yang-Zhou Su Hai-Bo Yang Fen-Hua Lu Yan Yang Xi-Wen liu Ping Wei Shu-Cai Wan hao-Qing Xie Xian-Qin {2. Cong Dai Hui-Jun Hu Hong-Bang liu Shu-Wen Tang Cheng-Xin Zhao Institute of Modern physics Chinese Academy of SciencesLanzhou 730000China School of Nuclear Science and Technology University of Chinese Academy of SciencesBeijing 100049China Guangxi key laboratory for Relativistic {2. School of Physical Science and TechnologyGuangxi UniversityNanning 530004China

The high energy cosmic-radiation detection(HERD)facility is planned to launch in 2.2. and scheduled to be installed on the {3. Space *** serves as a dark matter {2. detector,a cosmic ray instrument,and an observatory for high-energy gamma rays.A transition radiation detector placed on one of its lateral sides serves dual purpose,(ⅰ)calibrating HERD's electromagnetic calorimeter in the TeV energy range,and(ⅱ)serving as an independent detector for high-energy gamma *** this paper,the prototype readout electronics design of the transition radiation detector is demonstrated,which aims to accurately measure the charge of the anodes using the SAMPA application specific integrated circuit *** electronic performance of the prototype system is evaluated in terms of noise,linearity,and *** the presented design,each electronic channel can achieve a dynamic range of 0–100 fC,the RMS noise level not exceeding 0.15 fC,and the integral nonlinearity was2..To further verify the readout electronic performance,a joint test with the detector was carried out,and the results show that the prototype system can satisfy the requirements of the detector's scientific goals.

关键词： HERD Dark matter particle detection TRD Readout electronics SAMPA Data acquisition Performance test

Research on the knee region of cosmic ray by using a novel type of electron-neutron detector array

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Frontiers of physics 2024年第4期19卷 13-24页

作者： Bing-Bing li Xin-Hua Ma Shu-Wang Cui hao-Kun Chen Tian-Lu Chen Danzengluobu Wei Gao Hai-Bing Hu Denis Kuleshov Kirill Kurinov Hu {2. Mao-Yuan {2. Ye {2. Da-Yu Peng Yao-Hui Qi Oleg Shchegolev Yuri Stenkin li-Qiao Yin Heng-Yu Zhang liang-Wei Zhang College of physics Hebei Normal UniversityShijiazhuang 050024China key laboratory of {2. {3. Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China TIANFU Cosmic Ray Research Center Chengdu 610000China College of Science Tibet UniversityLhasa 850000China key laboratory of Comic Rays Ministry of EducationTibet UniversityLhasa 850000China Institute for Nuclear Research of the Russian academy of sciences Moscow 117312Russia School of Physical Science and Technology Southwest Jiaotong UniversityChengdu 610031China School of Management Science and Engineering Hebei University of Economics and BusinessShijiazhuang 050061China Moscow Institute of physics and Technology Moscow 141700Russia

By accurately measuring composition and energy spectrum of cosmic ray,the origin problem of so called“knee”region(energy>one PeV)can be ***,up to the present,the results of the spectrum in the knee region obtained by several previous experiments have shown obvious differences,so they cannot give effective evidence for judging the theoretical models on the origin of the ***,the Large High Altitude Air Shower Observatory(LHAASO)has reported several major breakthroughs and important results in astro-particle physics *** on its advantages of wide-sky survey,high altitude location and large area detector arrays,the research content of LHAASO experiment mainly includes ultra high-energy gamma-ray astronomy,measurement of cosmic ray spectra in the knee region,searching for dark matter and new phenomena of particle physics at higher *** electron and thermal neutron detector(EN-Detector)is a new scintillator detector which applies thermal neutron detection technology to measure cosmic ray extensive air shower(EAS).This technology is an extension of *** EN-Detector Array(ENDA)can highly efficiently measure thermal neutrons generated by secondary hadrons so called“skeleton”of *** this paper,we perform the optimization of ENDA configuration,and obtain expectations on the ENDA results,including thermal neutron distribution,trigger efficiency and capability of cosmic ray composition *** obtained real data results are consistent with those by the Monte Carlo simulation.

关键词： cosmic ray EAS knee region LHAASO ENDA

Missing completely of the CMB quadrupole in WMAP data

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chinese Science Bulletin 2013年第11期58卷 1243-1249页

作者： liu hao {2. {3. key laboratory of {2. {3. Institute of High Energy Physics Chinese Academy of Sciences Department of physics and Center for astrophysics Tsinghua University

In cosmic microwave background (CMB) experiments, foreground-cleaned temperature maps are still contaminated by the residual dipole due to uncertainties of the Doppler dipole direction and microwave radiometer sidelobe. To obtain reliable CMB maps, such contamination has to be carefully removed from observed data. We have previously built a software package for map-making, residual dipole-contamination removal, and power spectrum estimation from the Wilkinson Microwave Anisotropy Probe (WMAP) raw data. This software has now been significantly improved. With the improved software, we obtain a negative result of CMB quadrupole detection with the WMAP raw data, which is 3.2.3.5 K2.from the seven-year WMAP (WMAP7) data. This result is evidently incompatible with ～1000 K2.expected from the standard cosmological model ΛCDM. The completely missing of CMB quadrupole poses a serious challenge to the standard model and sets a strong constraint on possible models of cosmology. Due to the importance of this result for understanding the origin and early evolution of our universe, the software codes we used are opened for public checking.

关键词： WMAP 威尔金森微波各向异性探测器四级宇宙微波背景辐射标准宇宙模型地图制作原始数据微波辐射计

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 {2. {3. key laboratory of {2. {3. 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

Application of deep learning methods combined with physical background in wide field of view imaging atmospheric Cherenkov telescopes

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Nuclear Science and Techniques 2024年第4期35卷 208-220页

作者： Ao-Yan Cheng hao Cai Shi Chen Tian-Lu Chen Xiang Dong You-liang Feng Qi Gao Quan-Bu Gou Yi-Qing Guo Hong-Bo Hu Ming-Ming Kang Hai-Jin li Chen {3. Mao-Yuan {3. Wei {3. Fang-Sheng Min Chu-Cheng Pan Bing-Qiang Qiao Xiang-li Qian Hui-Ying Sun Yu-Chang Sun Ao-Bo Wang Xu Wang Zhen Wang Guang-Guang Xin Yu-Hua Yao Qiang Yuan Yi Zhang School of physics and Technology Wuhan UniversityWuhan 430072China School of physics and Astronomy Yunnan UniversityKunming 650091China Ministry of Education The Key Laboratory of Cosmic Rays(Tibet University)Lhasa 850000China key laboratory of {2. {3. Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China University of chinese academy of sciences 19 A Yuquan RoadShijingshan DistrictBeijing 100049China College of physics Sichuan UniversityChengdu 610064China School of Intelligent Engineering Shandong Management UniversityJinan 250357China Tsung‑Dao Lee Institute Shanghai Jiao Tong UniversityShanghai 200240China Suzhou Aerospace Information Research Institute Suzhou 215123China College of physics Chongqing UniversityNo.55 Daxuecheng South RoadHigh‑tech DistrictChongqing 401331China key laboratory of Dark Matter and Space Astronomy Purple Mountain ObservatoryChinese Academy of SciencesNanjing 210008China

The High Altitude Detection of Astronomical Radiation(HADAR)experiment,which was constructed in Tibet,china,combines the wide-angle advantages of traditional EAS array detectors with the high-sensitivity advantages of focused Cherenkov *** objective is to observe transient sources such as gamma-ray bursts and the counterparts of gravitational *** study aims to utilize the latest AI technology to enhance the sensitivity of HADAR *** datasets and models with distinctive creativity were constructed by incorporating the relevant physical theories for various *** models can determine the type,energy,and direction of the incident {2.s after careful *** obtained a background identification accuracy of 98.6%,a relative energy reconstruction error of 10.0%,and an angular resolution of 0.2.°in a test dataset at 10 *** findings demonstrate the significant potential for enhancing the precision and dependability of detector data analysis in astrophysical *** using deep learning techniques,the HADAR experiment’s observational sensitivity to the Crab Nebula has surpassed that of MAGIC and *** energies below 0.5 TeV and remains competitive with conventional narrow-field Cherenkov telescopes at higher *** addition,our experiment offers a new approach for dealing with strongly connected,scattered data.

关键词： VHE gamma-ray astronomy HADAR Deep learning Convolutional neural networks

Direct measurement of the break-out ^(19)F(p,γ)^(2.)Ne reaction in the china Jinping underground laboratory(CJPL)

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Nuclear Science and Techniques 2024年第8期35卷 142-152页

作者： Yin‑Ji Chen hao Zhang li‑Yong Zhang Jian‑Jun He Richard James deBoer Michael Wiescher Alexander Heger David Kahl Jun Su Daniel Odell Xin‑Yue li Jian‑Guo Wang Long Zhang Fu‑Qiang Cao Zhi‑Cheng Zhang Xin‑Zhi Jiang Luo‑Huan Wang Zi‑Ming li Lu‑Yang Song liang‑Ting Sun Qi Wu Jia‑Qing li Bao‑Qun Cui li‑Hua Chen Rui‑Gang Ma Er‑Tao li Gang lian Yao‑De Sheng Zhi‑Hong li Bing Guo Wei‑Ping liu key laboratory of Beam Technology of the Ministry of Education College of Nuclear Science and TechnologyBeijing Normal UniversityBeijing 100875China Department of physics and Astronomy The Joint Institute for Nuclear AstrophysicsUniversity of Notre DameNotre DameIN 46556USA School of physics and Astronomy Monash UniversityClaytonVIC 3800Australia Facility for Rare Isotope Beams Michigan State UniversityEast LansingMI 48824USA Institute of Nuclear and particle physics and Department of physics and Astronomy Ohio UniversityAthensOH 45701USA Institute of Modern physics Chinese Academy of SciencesLanzhou 730000China china Institute of Atomic Energy Beijing 102413China College of physics and Optoelectronic Engineering Shenzhen UniversityShenzhen 518060China School of Nuclear Science and Technology University of Chinese Academy of SciencesBeijing 100049China College of Science Southern University of Science and TechnologyShenzhen 518055China Institute of Radiation Technology Beijing Academy of Science and TechnologyBeijing 100875China key laboratory of Nuclear {2. and Ion‑Beam App{3.cation(MOE) Institute of Modern PhysicsFudan UniversityShanghai 200433China School of Mathematics and physics Handan UniversityHandan 056005China

Calcium production and the stellar evolution of first-generation stars remain fascinating mysteries in *** one possible nucleosynthesis scenario,break-out from the hot carbon–nitrogen–oxygen(HCNO)cycle was thought to be the source of the calcium observed in these oldest ***,according to the stellar modeling,a nearly tenfold increase in the thermonuclear rate ratio of the break-out ^(19)F(p,γ)^(2.) Ne reaction with respect to the competing ^(19)F(p,α)^(16) O back-processing reaction is required to reproduce the observed calcium *** performed a direct measurement of this break-out reaction at the china Jinping underground *** measurement was performed down to the low-energy limit of E_(c.m.)=186 keV in the center-of-mass *** key resonance was observed at 2.5.2.keV for the first *** a temperature of approximately 0.1 GK,this new resonance enhanced the thermonuclear ^(19)F(p,γ)^(2.) Ne rate by up to a factor of≈7.4,compared with the previously recommended NACRE *** is of particular interest to the study of the evolution of the first stars and implies a stronger breakdown in their“warm”CNO cycle through the ^(19)F(p,γ)^(2.) Ne reaction than previously *** break-out resulted in the production of the calcium observed in the oldest stars,enhancing our understanding of the evolution of the first stars.

关键词： Nuclear astrophysics First stars Abundance of calcium Reaction cross section Reaction rate china Jinping underground laboratory(CJPL) JUNA

A Localization Method of High Energy Transients for All-sky Gamma-ray Monitor

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Research in Astronomy and astrophysics 2024年第10期24卷 25-35页

作者： Yi Zhao Wangchen Xue Shao{2.n Xiong Qi Luo Yuanhao Wang Jiacong liu Heng Yu Xiaoyun Zhao Yue Huang Jinyuan {2.ao Jianchao Sun Xiaobo {2. Qibin Yi Ce Cai Shuo Xiao Shenglun Xie Chao Zheng Yanqiu Zhang Chenwei Wang Wenjun Tan Zhiwei Guo Chaoyang {2. Zhenghua An Gang Chen Yanqi Du Min Gao Ke Gong Dongya Guo Jiang He Jianjian He Bing {2. Gang {2. Xinqiao {2. Jing {2.ang Xiaohua {2.ang Yaqing liu Xiang Ma Rui Qiao {2.ming Song Xinying Song Xilei Sun Jin Wang Ping Wang Xiangyang Wen Hong Wu Yanbing Xu Sheng Yang Da{2. Zhang Fan Zhang Hongmei Zhang Peng Zhang Shu Zhang Zhen Zhang Shijie Zheng Keke Zhang Xingbo Han Haiyan Wu Hu Tai hao Geng Gaopeng Lu Wei Xu Fanchao Lyu Hongbo Zhang Fangjun Lu Shuangnan Zhang Department of Astronomy Beijing Normal UniversityBeijing 100875China key laboratory of {2. {3. Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China University of chinese academy of sciences Beijing 100049China School of physics and Optoelectronics Xiangtan UniversityXiangtan 411105China College of physics Hebei Normal UniversityShijiazhuang 050024China Guizhou Provincial key laboratory of Radio Astronomy and Data Processing Guizhou Normal UniversityGuiyang 550001China School of physics and Electronic Science Guizhou Normal UniversityGuiyang 550001China Institute of astrophysics Central China Normal UniversityWuhan 430079China College of physics sciences Technology Hebei UniversityBaoding 071002China physics and Space Science College China West Normal UniversityNanchong 637002China School of Computing and Artificial Intelligence Southwest Jiaotong UniversityChengdu 611756China College of Electronic and information Engineering Tongji UniversityShanghai 201804China Innovation academy for Microsatellites of {2. Shanghai 201304China National Space Science Center Chinese Academy of SciencesBeijing 100190China School of Earth and Space sciences University of Science and Technology of ChinaHefei 230026China Electronic Information School Wuhan UniversityWuhan 430072China key laboratory of Transportation Meteorology of {2. Meteorological Administration Nanjing Joint Institute for Atmospheric SciencesNanjing 210000China key laboratory of Middle Atmosphere and Global Environment Observation Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China

Fast and reliable localization of high-energy transients is crucial for characterizing the burst properties and guiding the follow-up *** based on the relative counts of different detectors has been widely used for all-sky gamma-ray *** are two major methods for this count distribution localization:χ^({3.minimization method and the Bayesian *** we propose a modified Bayesian method that could take advantage of both the accuracy of the Bayesian method and the simplicity of the χ^({3.*** comprehensive simulations,we find that our Bayesian method with Poisson likelihood is generally more applicable for various bursts than the χ^({3.method,especially for weak *** further proposed a location-spectrum iteration approach based on the Bayesian inference,which could alleviate the problems caused by the spectral difference between the burst and location *** method is very suitable for scenarios with limited computation resources or timesensitive applications,such as in-flight localization software,and low-latency localization for rapidly follow-up observations.

关键词： methods:data analysis methods:analytical (stars:)gamma-ray burst:general