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Searching for^(76)Ge neutrinoless double beta decay with the CDEX-1B experiment

Chinese Physics C 2024年第10期48卷 11-22页

作者： Bing-Tao zhang Jun-Zheng Wang li-Tao Yang Qian Yue Ke-Jun Kang Yuan-Jing li Hai-Peng An C.Greeshma jian-Ping Chang Yun-Huan Chen jian-Ping Cheng Wen-Han Dai Zhi Deng Chang-Hao Fang Xin-Ping Geng Hui Gong Qiu-Ju Guo Xu-Yuan Guo li He Sheng-Ming He Jin-Wei Hu Han-Xiong Huang Tu-Chen Huang Hai-Tao Jia Xi jiang S.Karmakar Hao-Bin li jian-Min li Jin li Qian-Yun li Ren-Ming-Jie li Xue-Qian li Yu-Lan li Yi-Fan liang Bin liao Fong-Kay lin Shin-Ted lin Jia-Xuan liu Shu-Kui liu Yan-Dong liu Yu liu Yuan-Yuan liu Zhong-Zhi liu Hao Ma Yu-Cai Mao Qi-Yuan Nie Jin-Hua Ning Hui Pan Ning-Chun Qi Jie Ren Xi-Chao Ruan Ze She Manoj Kumar Singh Tian-Xi Sun Chang-jian Tang Wei-You Tang Yang Tian Guang-Fu Wang li Wang Qing Wang Yu-Feng Wang Yun-Xiang Wang Henry-Tsz-King Wong Shi-yong Wu Yu-Cheng Wu Hao-Yang Xing Rui Xu Yin Xu Tao Xue Yu-Lu Yan nan Yi Chun-Xu Yu Hai-Jun Yu jian-Feng Yue Ming Zeng Zhi Zeng Feng-Shou zhang Lei zhang Zhen-Hua zhang Zhen-Yu zhang Kang-Kang zhao Ming-Gang zhao Ji-Fang Zhou Zu-Ying Zhou Jing-Jun Zhou Key Laboratory of Particle and Radiation Imaging(Ministry of Education)and Department of Engineering Physics Tsinghua UniversityBeijing 100084 Department of Physics Tsinghua UniversityBeijing 100084 Institute of Physics Academia SinicaTaipei 11529 NUCTECH Company Beijing 100084 YaLong River Hydropower Development Company Chengdu 610051 College of Nuclear Science and Technology Beijing Normal UniversityBeijing 100875 College of Physics Sichuan UniversityChengdu 610065 School of Physics Peking UniversityBeijing 100871 Department of Nuclear Physics China Institute of Atomic EnergyBeijing 102413 Sino-French Institute of Nuclear and Technology Sun Yat-sen UniversityZhuhai 519082 School of Physics Nankai UniversityTianjin 300071 Department of Physics Banaras Hindu UniversityVaranasi 221005 Department of Physics Beijing Normal UniversityBeijing 100875

We operated a p-type point contact high purity germanium(PPCGe)detector(CDEX-1B,1.008 kg)in the China Jinping Underground Laboratory(CJPL)for 500.3 days to search for neutrinoless double beta(0νββ)decay of^(76)Ge.A total of 504.3 kg⋅day effective exposure data was *** anti-coincidence and the multi/single-site event(MSE/SSE)discrimination methods were used to suppress the background in the energy region of interest(ROI,1989–2089 keV for this work)with a factor of 23.A background level of 0.33 counts/(keV⋅kg⋅yr)was *** lower limit on the half life of^(76)Ge 0νββdecay was constrained as T_(1/2)^(0ν)>1.0×10^(23)yr(90%C.L.),corresponding to the upper limits on the effective Majorana neutrino mass:<3.2–7.5 eV.

关键词： neutrinoless double beta decay CDEX point-contact germanium detector ^(76)Ge

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Relative flux calibration for the Guoshoujing Telescope (LAMOST)

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Research in Astronomy and Astrophysics 2012年第4期12卷 453-464页

作者： Yi-Han Song A-li luo Georges Comte Zhong-Rui Bai jian-nan zhang Wei Du Hao-Tong zhang jian-Jun Chen Fang Zuo yong-heng zhao National Astronomical Observatories Chinese Academy of SciencesBeijing 100012China Key Laboratory of Optical Astronomy National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100012China Graduate University of Chinese Academy of Sciences Beijing 100049China Observatoire Astronomique Marseille-Provence and Laboratoire d'Astrophysique de Marseille F-13388 Marseille CedexFrance

This paper presents a relative flux calibration method for the Guoshoujing Telescope （LAMOST）, which may be applied to connect a blue spectrum to a red spectrum to build the whole spectrum across the total wavelength range （3700 ～ 9000 A）. In each spectrograph, we estimate the effective temperatures of selected stars using a grid of spectral line indices in the blue spectral range and a comparison with stellar atmosphere models. For each spectrograph, stars of types A and F are selected as pseudo-standard stars, and the theoretical spectra are used to calibrate both the blue （3700 ～ 5900 A） and red spectrograph arms （5700 ～ 9000 A）. Then the spectral response function for these pseudo-standard stars could be used to correct the raw spectra provided by the other fibers of the spectrograph, after a fiber efficiency function has been derived from twilight flat-field exposures. A key problem in this method is the fitting of a pseudo stellar continuum, so we also give a detailed description of this step. The method is tested by comparing a small sample of LAMOST spectra calibrated in this way on stars also observed by the Sloan Digital Sky Survey. The result shows that the T eff estimation and relative flux calibration method are adequate.

关键词： techniques: spectroscopic — calibration: methods:data analysis

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Identifying Carbon stars from the LAMOST pilot survey with the efficient manifold ranking algorithm

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Research in Astronomy and Astrophysics 2015年第10期15卷 1671-1694页

作者： jian-Min Si Yin-Bi li A-li luo liang-Ping Tu Zhi-Xin Shi jian-nan zhang Peng Wei Gang zhao Yi-Hong Wu Fu-Chao Wu yong-heng zhao Key Laboratory of Optical Astronomy National Astronomical ObservatoriesChinese Academy of Sciences National Key Laboratory of Pattern Recognition Institute of AutomationChinese Academy of Sciences University of Chinese Academy of Sciences School of Science Liaoning University of Science and Technology

Carbon stars are excellent kinematic tracers of galaxies and can serve as a viable standard candle, so it is worthwhile to automatically search for them in a large amount of spectra. In this paper, we apply the efficient manifold ranking algorithm to search for carbon stars from the Large Sky Area Multi-Object Fiber Spectroscopic Telescope （LAMOST） pilot survey, whose performance and robustness are verified comprehensively with four test experiments. Using this algorithm, we find a total of 183 carbon stars, and 158 of them are new findings. According to different spectral features, our carbon stars are classified as 58 C-H stars, 11 C-H star candidates, 56 C-R stars, ten C-R star candidates, 30 C-N stars, three C-N star candidates, and four C-J stars. There are also ten objects which have no spectral type because of low spec- tral quality, and a composite spectrum consisting of a white dwarf and a carbon star. Applying the support vector machine algorithm, we obtain the linear optimum clas- sification plane in the J - H versus/-/- Ks color diagram which can be used to distinguish C-H from C-N stars with their J - H and H - Ks colors. In addition, we identify 18 dwarf carbon stars with their relatively high proper motions, and find three carbon stars with FUV detections likely have optical invisible companions by cross matching with data from the Galaxy Evolution Explorer. In the end, we detect four variable carbon stars with the Northern Sky Variability Survey, the Catalina Sky Survey and the liNEAR variability databases. According to their periods and ampli- tudes derived by fitting light curves with a sinusoidal function, three of them are likely semiregular variable stars and one is likely a Mira variable star.

关键词： methods: data analysis -- methods: statistical -- stars: carbon -- binaries-- stars: variables

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The discovery of 64 luminous infrared galaxies in the LAMOST Complete Spectroscopic Survey of Pointing Area at the Southern Galactic Cap

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Research in Astronomy and Astrophysics 2015年第8期15卷 1424-1437页

作者： Man I Lam Hong Wu Ming Yang Yi-nan Zhu jian-Rong Shi Hao-Tong zhang A-li luo Shi-Yin Shen yong zhang yong-Hui Hou Guang-Wei li yong-heng zhao Key Laboratory of Optical Astronomy National Astronomical ObservatoriesChinese Academy of Sciences University of Chinese Academy of Sciences Key Laboratory for Research in Galaxies and Cosmology Shanghai Astronomical ObservatoryChinese Academy of Sciences nanjing Institute of Astronomical Optics & Technology National Astronomical ObservatoriesChinese Academy of Sciences

We report the discovery of 64 luminous infrared galaxies, based on new observations of 20 square degrees from the LAMOST Complete Spectroscopic Survey of Pointing Area at the Southern Galactic Cap and the WISE 22 μm catalog from the AllW ISE Data Release. Half of them are classified as late-type spirals and the others are classified as peculiar/compact galaxies. The peculiar/compact galaxies tend to exhibit higher luminosities and lower stellar masses. We also separate AGNs from HII galaxies in a simple way by examining LAMOST spectra. Those cases show that host AGNs are easily distinguished from others in the mid-infrared color-color diagrams.

关键词： galaxies: statistic—galaxies: structure—galaxies: starburst—galaxies: spiral—galaxies: interactions—infrared: galaxies

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Automatic determination of stellar atmospheric parameters and construction of stellar spectral templates of the Guoshoujing Telescope (LAMOST)

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Research in Astronomy and Astrophysics 2011年第8期11卷 924-946页

作者： Yue Wu A-li luo Hai-Ning li jian-Rong Shi Philippe Prugniel Yan-Chun liang yong-heng zhao jian-nan zhang Zhong-Rui Bai Peng Wei Wei-Xiang Dong Hao-Tong zhang jian-Jun Chen National Astronomical Observatories Chinese Academy of Sciences Beijing 100012 China Universitede Lyon Universite Lyon 1 Villeurbanne F-69622 France CRAL Observatoire de Lyon CNRS UMR 5574 69561 Saint-Genis Laval France Key Laboratory of Optical Astronomy NAOC Chinese Academy of Sciences Graduate University of Chinese Academy of Sciences Beijing 100049 China Shandong University at Weihai Weihai 264209 China

A number of spectroscopic surveys have been carried out or are planned to study the origin of the Milky Way. Their exploitation requires reliable automated methods and softwares to measure the fundamental parameters of the stars. Adopting the ULySS package, we have tested the effect of different resolutions and signal-to- noise ratios （SNR） on the measurement of the stellar atmospheric parameters （effective temperature Teff, surface gravity log g, and metaUicity [Fe/H]）. We show that ULySS is reliable for determining these parameters with medium-resolution spectra （R ～2000）. Then, we applied the method to measure the parameters of 771 stars selected in the commissioning database of the Guoshoujing Telescope （LAMOST）. The results were compared with the SDSS/SEGUE Stellar Parameter Pipeline （SSPP）, and we derived precisions of 167 K, 0.34dex, and 0.16dex for Teff, logg and [Fe/H] respectively. Furthermore, 120 of these stars are selected to construct the primary stellar spectral template library （Version 1.0） of LAMOST, and will be deployed as basic ingredients for the LAMOST automated parametrization pipeline.

关键词： astronomical data bases: atlases -- stars: fundamental parameters techniques: spectroscopic -- surveys

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M100大型电渣重熔板坯表面裂纹成因与控制

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中国冶金 2024年第8期34卷 69-82页

作者：李健赵刚柴锋张友鹏罗小兵潘涛钢铁研究总院有限公司工程用钢研究院北京100081 鞍钢钢铁研究院辽宁鞍山114009

M100钢是一种采用电渣工艺生产的高强度船体结构用钢,其在电渣重熔过程中产生的表面裂纹会对产品的成材率和表面质量产生不利影响。针对M100大型电渣板坯出现的表面裂纹问题,利用残余应力、低倍组织、裂纹形貌、微观组织分析及硬度测试... 详细信息

M100钢是一种采用电渣工艺生产的高强度船体结构用钢,其在电渣重熔过程中产生的表面裂纹会对产品的成材率和表面质量产生不利影响。针对M100大型电渣板坯出现的表面裂纹问题,利用残余应力、低倍组织、裂纹形貌、微观组织分析及硬度测试等方法,对电渣板坯表面裂纹特征及形成机理进行了研究。结果表明,电渣板坯表面裂纹多沿粗大柱状晶晶界分布,其断口呈典型的沿晶断裂特征;裂纹处存在明显氧化现象,表明裂纹主要产生于电渣板坯凝固冷却阶段。对电渣板坯表面裂纹形成机理进行了分析,发现表层金属在结晶器较大冷却强度作用下,所形成的粗大马氏体柱状晶晶间结合力弱,受马氏体相变瞬间产生的组织拉应力作用而开裂,是试验电渣板坯产生表面沿晶裂纹的主要原因。基于表面裂纹形成机理,提出了将结晶器冷却水流量由130 m^(3)/h降低至80 m^(3)/h的工艺优化措施并进行了工业试验,验证电渣板坯主要由马氏体和贝氏体混合组织组成,平均硬度较优化前的电渣板坯降低约40HV10,表面未发现裂纹,表明所采取的结晶器冷速优化措施合理有效。研究结果可为马氏体型合金钢大型板坯电渣生产中表面质量的控制提供参考。

关键词： M100钢电渣板坯表面裂纹结晶器冷却强度组织应力

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Photocatalyst with Chloroplast-like Structure for Enhancing Hydrogen Evolution Reaction

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Energy & Environmental Materials 2022年第4期5卷 1229-1237页

作者： Fei zhao nan zhang Hao li Xiaochen zhang Zhengtang luo Yuhua Wang National&Local Joint Engineering Laboratory for Optical Conversion Materials and Technology Lanzhou UniversityLanzhou 730000China Department of Materials Science School of Physical Science and TechnologyLanzhou UniversityLanzhou 730000China Department of Chemical and Biomolecular Engineering Hong Kong University of Science and TechnologyClear Water BayKowloonHong Kong 999077China

Photosynthesis with the chloroplast works efficiently because of the envelope structure that serves to carry enzymes and to simultaneously maintain the spatial separation of photosynthesis and cellular *** by the spatially separated architecture,a chloroplast-like structured photocatalyst(PdS@CdS@MoS_(2)),in which the PdS and MoS_(2) function as enzymes in the chloroplast and CdS shell functions as the chloroplast envelope,was developed to improve the photocatalytic H_(2) *** this unique nanoscale bionic structure,the poriferous CdS shell enhances light absorption,generates photoinduced carriers,and separates oxidation and reduction ***,PdS and MoS_(2) dual cocatalysts enhance the charge separation efficiency through forming a built-in electric field with *** demonstrate that the separation efficiency of carriers,carrier lifetime,and the yield of H_(2) are both higher than that of CdS nanoparticles,evidencing the feasibility of the chloroplast-like structure in enhancing the photocatalyst *** work emphasizes the synergism of the three key processes of the photocatalytic reaction by simulating the chloroplast structure and provides a general synthesis strategy,the synthesis of novel structured for photocatalysts for diverse applications in the energy field.

关键词： chloroplast-like structure co-catalysts DFT calculations photocatalytic H_(2)evolution spatial separation of carriers

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Numerical simulation of seasonal snow in Tianshan Mountains

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Journal of Mountain Science 2021年第2期18卷 338-356页

作者： REN Yan-run zhang Yao-nan HAO jian-sheng SHEN yong-ping zhao Guo-hui li Cong Northwest Institute of Eco-Environment and Resources Chinese Academy of SciencesLanzhou 730000China University of Chinese Academy of Sciences Beijing 100049China National Cryosphere Desert Data Center Lanzhou 730000China Institute of Geographic Sciences and Natural Resources Research Chinese Academy of SciencesBeijing 100101China Lanzhou University of Technology Lanzhou 730050China

Snowfall in the Tianshan Mountains in China is frequent during winter;thus,avalanches have become a severe issue in snow-covered *** and metamorphosis,as well as hydrothermal exchanges with the environment,considerably affect the stability of snow on ***,a hydrothermal model of snow cover and its underlying surfaces must be developed on the basis of meteorological data to predict and help manage *** study adopted the conceptual model of snow as a porous medium and quantitatively analysed its internal physical processes on the basis of the thermal exchanges amongst its *** effects of local meteorological factors on snow structure and the redistribution of energy and mass inside the snow cover in the Tianshan Mountains were *** results showed that deformation as a result of overlying snow and sublimation of snow cover at the bottom is the main cause of density variation in the vertical profile of snow *** drives water movement in *** low-density area of the bottom snow is the result of temperature *** simulation results of the long-term snow internal mass distribution obtained by the method established in this study are highly consistent with the actual observed trend of *** consistency indicates an accurate simulation of the physical characteristics of snow cover in small and microscale metamorphism in the Tianshan Mountains during the stable period.

关键词： Snow Porous medium Heat and mass transfer Phase change Thermo-hydro-mechanical(THM)coupling Numerical modelling

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A sample of E+A galaxy candidates in the Second Data Release of LAMOST Survey

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Research in Astronomy and Astrophysics 2015年第8期15卷 1414-1423页

作者： Hai-Feng Yang A-li luo Xiao-Yan Chen Wen Hou jian-nan zhang Wei Du Ji-Fu zhang jiang-Hui Cai Yan-Xin Guo Shuo zhang yong-heng zhao Hong Wu Ting-Gui Wang Shi-Yin Shen Ming Yang yong zhang yong-Hui Hou Key Laboratory of Optical Astronomy National Astronomical ObservatoriesChinese Academy of Sciences School of Computer Science and Technology Taiyuan University of Science and Technology University of Chinese Academy of Sciences Center for Astrophysics University of Science & Technology of China Shanghai Astronomical Observatory Chinese Academy of Sciences nanjing Institute of Astronomical Optics & Technology National Astronomical ObservatoriesChinese Academy of Sciences

A sample of 70 E＋A galaxies is selected from 37 206 galaxies in the second data release of the Large Sky Area Multi-Object Fiber Spectroscopic Telescope（LAMOST）. This sample is selected according to the criteria for E＋A galaxies defined by Goto, and each of these objects is further visually identified. In this sample, most objects are low redshift E＋A galaxies with z 〈 0.25, and are located in an area of the sky with high Galactic latitude and magnitude from 14 to 18 mag in the g, r and i bands. A stellar population analysis of the whole sample indicates that the E＋A galaxies are characterized by both young and old stellar populations（SPs）, and the metalrich SPs have relatively higher contributions than the metal-poor ones. Additionally, a morphological classification of these objects is performed based on images taken from the Sloan Digital Sky Survey.

关键词： galaxies: evolution—galaxies: formation—galaxies: interactions—galaxies: peculiar—galaxies: starburst

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Preparation and Supercapacitive Properties of Fe_2O_3/Active Carbon nanocomposites

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Chemical Research in Chinese Universities 2012年第5期28卷 780-783页

作者： luo Pei-wen YU jian-guo SHI Zhi-qiang HUANG Hua liU Lang zhao yong-nan li Guo-dong ZOU yong-cun Institute of nanostructured Materials&Tianjin Key Laboratory of Fiber Modification and Functional Fiber School of Materials Science and EngineeringTianjin Polytechnic UniversityTianjin 300160P R.China State Key Laboratory of Inorganic Synthesis and Preparative Chemistry College of ChemistryJilin UniversityChangchun 130012P.R.China

Fe2O3/active carbon（Fe2O3/AC） nanocomposites were readily fabricated by pyrolyzing Fe3＋ impregnated active carbon in a nitrogen atmosphere. The as-prepared composites were studied by X-ray powder diffraction（XRD）, X-ray photoelectron spectroscopy（XPS） and transmission electron microscopy（TEM）. The capacitive property of the composites was investigated by cyclic voltammetry（CV） and galvanostatic charge-discharge test. Physical characterizations show that the γ-Fe2O3 fine grains dispersed in the AC well, with a mean size of 21.24 nm. Electrochemical tests in 6 mol/L KOH solutions indicate that the as-prepared nanocomposites exhibited improved capacitive properties. The specific capacitance（SC） of Fe2O3/AC nanocomposites was up to 188.4 F/g that was derived from both electrochemical double-layer capacitance and pseudo-capacitance, which was 78% larger than that of pristine AC. A symmetric capacitor with Fe2O3/AC nanocomposites as electrode showed an excellent cycling stability. The SC was only reduced by a factor of 9.2% after 2000 cycles at a current density of 1 A/g.

关键词： nanocomposite Fe2O3 Active carbon Supercapacitor

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