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Charge Breeding Simulations in a Hollow Electron Beam
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作者 Vincenzo Variale 《Journal of Energy and Power Engineering》 2013年第3期596-602,共7页
Charge breeding technique is used for RIB (radioactive ion beam) production in order of optimizing the re-acceleration of the radioactive isotopes produced by a primary beam in a thick target. Charge breeding is ach... Charge breeding technique is used for RIB (radioactive ion beam) production in order of optimizing the re-acceleration of the radioactive isotopes produced by a primary beam in a thick target. Charge breeding is achieved by means of a device capable of increasing the ion charge state from 1+ to a desired value n+. In some experiments, a continuous RIB of a given energy may be required. To reach this goal, a charge breeding device based on a hollow gun EBIS (electron beam ion source) has been proposed by the author recently. That EBIS, in principle, can be capable to realize a CW (continuous wave) operation. A sufficiently high focusing magnetic field could reduce to zero the hole radius in the EBIS electron beam. However, a smaller efficiency in the ion charge state increase should be expected. A code developed for studying the ion selective containment in a EBIS has been modified and used to simulate the ion charge state breeding. The effects of the hollow electron beam on the breeding rate have been studied. 展开更多
关键词 High charge state ions ion source radioactive ion beam.
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The Way to Quench:Galaxy Evolution in A2142
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作者 Cheng-Gong Qu Heng Yu +2 位作者 Antonaldo Diaferio Jubee Sohn DengQi Liu 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2023年第8期127-140,共14页
We show how the star formation activity of galaxies is progressively inhibited from the outer region to the center of the massive cluster A2142.From an extended spectroscopic redshift survey of 2239 galaxies covering ... We show how the star formation activity of galaxies is progressively inhibited from the outer region to the center of the massive cluster A2142.From an extended spectroscopic redshift survey of 2239 galaxies covering a circular area of radius~11 Mpc from the cluster center,we extract a sample of 333 galaxies with known stellar mass,star formation rate,and spectral index D_(n)4000.We use the Blooming Tree algorithm to identify the substructures of the cluster and separate the galaxy sample into substructure galaxies,halo galaxies,and outskirt galaxies.The substructure and halo galaxies are cluster members,whereas the outskirt galaxies are only weakly gravitationally bound to the cluster.For the cluster members,the star formation rate per stellar mass decreases with decreasing distance R from the cluster center.Similarly,the spectral index D_(n)4000 increases with R,indicating an increasing average age of the stellar population in galaxies closer to the cluster center.In addition,star formation in substructure galaxies is generally more active than in halo galaxies and less active than in outskirt galaxies,proving that substructures tend to slow down the transition between field galaxies and cluster galaxies.We finally show that most actively star-forming galaxies are within the cluster infall region,whereas most galaxies in the central region are quiescent. 展开更多
关键词 GALAXIES CLUSTERS individual(A2142)-galaxies star formation-galaxies EVOLUTION
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Primordial black hole mass functions as a probe of cosmic origin
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作者 Yi-Fu Cai Chengfeng Tang +7 位作者 Geyu Mo Sheng-Feng Yan Chao Chen Xiao-Han Ma Bo Wang Wentao Luo Damien A.Easson Antonino Marcianò 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS CSCD 2024年第5期164-171,共8页
We discuss a novel window to probe the origin of our universe via the mass functions of primordial black holes(PBHs).The mass functions of PBHs are simply estimated using the conventional Press-Schechter formalism for... We discuss a novel window to probe the origin of our universe via the mass functions of primordial black holes(PBHs).The mass functions of PBHs are simply estimated using the conventional Press-Schechter formalism for two paradigms of cosmic origin,including inflationaryΛCDM and bounce cosmology.The standard inflationaryΛCDM model cannot generate an appreciable number of massive PBHs;however,non-trivial inflation models with blue-tilted power spectra at small scales and matter bounce cosmology provide formation mechanisms for heavy PBHs,which in turn,may seed the observed supermassive black holes(SMBHs).By fitting the SMBH mass functions at high redshift(z~6)derived from Sloan Digital Sky Survey(SDSS)and Canada-France High-z Quasar Survey(CFHQS)quasars,for two paradigms of cosmic origin,we derive constraints on the PBH density fraction fPBHat z~6 and the characteristic mass M_(★),with the prior assumption that all SMBHs stem from PBHs.We demonstrate that this newly proposed procedure,relying on astronomical measurements that utilize deep-field surveys of SMBHs at high redshift,can be used to constrain models of cosmic origin.Additionally,although not the main focus of this paper,we evolve the mass function from z~6 to z~0 through an assumption of 3×10^(8)-year Eddington’s accretion,and give a rough estimation of fPBHat z~0. 展开更多
关键词 ORIGIN COSMIC MASSIVE
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Comparison of Proton Shower Developments in the BGO Calorimeter of the Dark Matter Particle Explorer between GEANT4 and FLUKA Simulations 被引量:1
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作者 Wei Jiang Chuan Yue +30 位作者 Ming-Yang Cui Xiang Li Qiang Yuan Francesca Alemanno Paolo Bernardini Giovanni Catanzani Zhan-Fang Chen Ivan De Mitri Tie-Kuang Dong Giacinto Donvito David Francois Droz Piergiorgio Fusco Fabio Gargano Dong-Ya Guo Dimitrios Kyratzis Shi-Jun Lei Yang Liu Francesco Loparco Peng-Xiong Ma Giovanni Marsella Mario Nicola Mazziotta Xu Pan Wen-Xi Peng Antonio Surdo Andrii Tykhonov Yi-Yeng Wei Yu-Hong Yu Jing-Jing Zang Ya-Peng Zhang Yong-Jie Zhang Yun-Long Zhang 《Chinese Physics Letters》 SCIE CAS CSCD 2020年第11期114-120,共7页
The DArk Matter Particle Explorer(DAMPE)is a satellite-borne detector for high-energy cosmic rays and y-rays.To fully understand the detector performance and obtain reliable physical results,extensive simulations of t... The DArk Matter Particle Explorer(DAMPE)is a satellite-borne detector for high-energy cosmic rays and y-rays.To fully understand the detector performance and obtain reliable physical results,extensive simulations of the detector are necessary.The simulations are particularly important for the data analysis of cosmic ray nuclei,which relies closely on the hadronic and nuclear interactions of particles in the detector material.Widely adopted simulation softwares include the GEANT4 and FLUKA,both of which have been implemented for the DAMPE simulation tool.Here we describe the simulation tool of DAMPE and compare the results of proton shower properties in the calorimeter from the two simulation softwares.Such a comparison gives an estimate of the most significant uncertainties of our proton spectral analysis. 展开更多
关键词 material. GEANT4 CALORIMETER
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Calibration of the DAMPE Plastic Scintillator Detector and its on-orbit performance
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作者 Meng Ding Ya-Peng Zhang +17 位作者 Yong-Jie Zhang Yuan-Peng Wang Tie-Kuang Dong Antonio De Benedittis Paolo Bernardini Fang Fang Yao Li Jie Liu Peng-Xiong Ma Zhi-Yu Sun Valentina Gallo Stefania Vitillo Zhao-Min Wang Yu-Hong Yu Chuan Yue Qiang Yuan Yong Zhou Yun-Long Zhang 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2019年第3期145-154,共10页
The DArk Matter Particle Explorer(DAMPE) is a space-borne apparatus for detecting the highenergy cosmic-ray-like electrons, γ-rays, protons and heavy ions. The Plastic Scintillator Detector(PSD)is the top-most sub-de... The DArk Matter Particle Explorer(DAMPE) is a space-borne apparatus for detecting the highenergy cosmic-ray-like electrons, γ-rays, protons and heavy ions. The Plastic Scintillator Detector(PSD)is the top-most sub-detector of the DAMPE. The PSD is designed to measure the charge of incident highenergy particles and it also serves as a veto detector for discriminating γ-rays from charged particles. In this paper, a PSD on-orbit calibration procedure is described, which includes the five steps of pedestal, dynode correlation, response to minimum-ionizing particles, light attenuation function and energy reconstruction.A method for reconstructing the charge of incident high energy cosmic-ray particles is introduced. The detection efficiency of each PSD strip is verified to be above 99.5%; the total efficiency of the PSD for charged particles is above 99.99%. 展开更多
关键词 COSMIC RAY instrumentation: DAMPE charge measurement plastic scintillator detector CALIBRATION
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A machine learning method to separate cosmic ray electrons from protons from 10 to 100 GeV using DAMPE data
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作者 Hao Zhao Wen-Xi Peng +4 位作者 Huan-Yu Wang Rui Qiao Dong-Ya Guo Hong Xiao Zhao-Min Wang 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2018年第6期99-108,共10页
DArk Matter Particle Explorer(DAMPE) is a general purpose high energy cosmic ray and gamma ray observatory, aiming to detect high energy electrons and gammas in the energy range 5 Ge V to 10 Te V and hundreds of Te V ... DArk Matter Particle Explorer(DAMPE) is a general purpose high energy cosmic ray and gamma ray observatory, aiming to detect high energy electrons and gammas in the energy range 5 Ge V to 10 Te V and hundreds of Te V for nuclei. This paper provides a method using machine learning to identify electrons and separate them from gammas, protons, helium and heavy nuclei with the DAMPE data acquired from 2016 January 1 to 2017 June 30, in the energy range from 10 to 100 Ge V. 展开更多
关键词 astroparticle physics methods: data analysis cosmic rays
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Enhancing Eucalyptus Community Cloud
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作者 Andrea Bosin Matteo Dessalvi +1 位作者 Gian Mario Mereu Giovanni Serra 《Intelligent Information Management》 2012年第3期52-59,共8页
In the last few years, the cloud computing model has moved from hype to reality, as witnessed by the increasing number of commercial providers offering their cloud computing solutions. At the same time, various open-s... In the last few years, the cloud computing model has moved from hype to reality, as witnessed by the increasing number of commercial providers offering their cloud computing solutions. At the same time, various open-source projects are developing cloud computing frameworks open to experimental instrumentation and study. In this work we analyze Eucalyptus Community Cloud, an open-source cloud-computing framework delivering the IaaS model and running under the Linux operating system. Our aim is to present some of the results of our analysis and to propose some enhancements that can make Eucalyptus Community Cloud even more attractive for building both private and community cloud infrastructures, but also with an eye toward public clouds. In addition, we present a to-do list that may hopefully help users in the task of configuring and running their own Linux (and Windows) guests with Eucalyptus. 展开更多
关键词 CLOUD IAAS EUCALYPTUS KVM qcow2
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Indoor Radon Concentrations in Dwellings of Ischia Island
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作者 Mariagabriella Pugliese Maria Quarto +2 位作者 Filomena Loffredo Agostino Mazzella Vincenzo Roca 《Journal of Environmental Protection》 2013年第8期37-39,共3页
Indoor radon concentration measurements were performed in dwellings of Ischia island (South Italy) using commercial E-Perm devices in LST configuration. The average concentrations in the dwellings were found to vary f... Indoor radon concentration measurements were performed in dwellings of Ischia island (South Italy) using commercial E-Perm devices in LST configuration. The average concentrations in the dwellings were found to vary from 125 to 865 Bq/m3 with an average of 354 ± 176 Bq/m3. This value is higher than Italian National average that is 75 Bq/m3 and Campanian average that is 95 Bq/m3. Correlation between indoor radon concentration measurements and floor level of monitored room was also studied. 展开更多
关键词 RADON E-Perm FLOOR Level
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Microscopic Study on Isoscalar Giant Monopole Resonance in Cd, Sn and Pb Isotopes
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作者 Cao Ligang H. Sagawa G. Colo 《IMP & HIRFL Annual Report》 2011年第1期19-21,共3页
关键词 铅同位素 微观 共振 单极 非相对论 重离子碰撞 多体系统 压缩模式
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Optical diagnostics for density measurement in high-quality laser-plasma electron accelerators 被引量:2
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作者 Fernando Brandi Leonida Antonio Gizzi 《High Power Laser Science and Engineering》 SCIE CAS CSCD 2019年第2期40-50,共11页
Implementation of laser-plasma-based acceleration stages in user-oriented facilities requires the definition and deployment of appropriate diagnostic methodologies to monitor and control the acceleration process.An ov... Implementation of laser-plasma-based acceleration stages in user-oriented facilities requires the definition and deployment of appropriate diagnostic methodologies to monitor and control the acceleration process.An overview is given here of optical diagnostics for density measurement in laser-plasma acceleration stages,with emphasis on wellestablished and easily implemented approaches.Diagnostics for both neutral gas and free-electron number density are considered,highlighting real-time measurement capabilities.Optical interferometry,in its various configurations,from standard two-arm to more advanced common-path designs,is discussed,along with spectroscopic techniques such as Stark broadening and Raman scattering.A critical analysis of the diagnostics presented is given concerning their implementation in laser-plasma acceleration stages for the production of high-quality GeV electron bunches. 展开更多
关键词 gas target interferometry LASER-PLASMA laser WAKE-FIELD acceleration RAMAN scattering STARK BROADENING
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Overview and specifications of laser and target areas at the Intense Laser Irradiation Laboratory
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作者 Leonida A.Gizzi Luca Labate +5 位作者 Federica Baffigi Fernando Brandi Giancarlo Bussolino Lorenzo Fulgentini Petra Köster Daniele Palla 《High Power Laser Science and Engineering》 SCIE CAS CSCD 2021年第1期94-102,共9页
We present the main features of the ultrashort, high-intensity laser installation at the Intense Laser Irradiation Laboratory(ILIL) including laser, beam transport and target area specifications. The laboratory was de... We present the main features of the ultrashort, high-intensity laser installation at the Intense Laser Irradiation Laboratory(ILIL) including laser, beam transport and target area specifications. The laboratory was designed to host laser–target interaction experiments of more than 220 TW peak power, in flexible focusing configurations, with ultrarelativistic intensity on the target. Specifications have been established via dedicated optical diagnostic assemblies and commissioning interaction experiments. In this paper we give a summary of laser specifications available to users,including spatial, spectral and temporal contrast features. The layout of the experimental target areas is presented, with attention to the available configurations of laser focusing geometries and diagnostics. Finally, we discuss radiation protection measures and mechanical stability of the laser focal spot on the target. 展开更多
关键词 high-intensity laser laser focusing laser–plasma acceleration laboratory pointing stability radiation shielding ultrashort pulse amplification
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脉冲星计时阵列观测的随机背景信号对标量诱导引力波的限制 被引量:3
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作者 蔡一夫 何鑫宸 +2 位作者 马潇汉 鄢盛丰 袁官文 《Science Bulletin》 SCIE EI CAS CSCD 2023年第23期2929-2935,M0004,共8页
最近,NANOGrav、PPTA、EPTA和CPTA合作组各自独立报告了关于随机引力波背景的观测证据.尽管根据观测推断的引力波背景(幅度、频谱)与超大质量双黑洞并合的预言相一致,但这一观测也为搜寻宇宙早期的新物理现象提供了新的窗口.本文探讨了... 最近,NANOGrav、PPTA、EPTA和CPTA合作组各自独立报告了关于随机引力波背景的观测证据.尽管根据观测推断的引力波背景(幅度、频谱)与超大质量双黑洞并合的预言相一致,但这一观测也为搜寻宇宙早期的新物理现象提供了新的窗口.本文探讨了用早期宇宙中的标量诱导引力波来解释这一信号的可能性.作者采用参数化的拐折幂律谱作为随机引力波背景能谱的普适性描述,利用NANOGrav、PPTA和EPTA的新数据和贝叶斯推断的方法进行研究.本研究结果可以约束诱导引力波能谱的相关参数,并进一步对可能在早期宇宙中产生原初黑洞的各种暴胀模型给出限制,这些模型有望在未来的空间引力波观测实验中得到检验. 展开更多
关键词 Pulsar timing array observation Bayesian inference Stochastic gravitational wave background Induced gravitational waves Early universe
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The HEPD particle detector of the CSES satellite mission for investigating seismo-associated perturbations of the Van Allen belts 被引量:6
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作者 AMBROSI Giovanni BARTOCCI Simona +39 位作者 BASARA Laurent BATTISTON Roberto BURGER William J. CARFORA Luca CASTELLINI Guido CIPOLLONE Piero CONTI Livio CONTIN Andrea DE DONATO Cinzia DE SANTIS Cristian FOLLEGA Francesco M. GUANDALINI Cristina IONICA Maria IUPPA Roberto LAURENTI Giuliano LAZZIZZERA Ignazio LOLLI Mauro MANEA Christian MARCELLI Laura MASCIANTONIO Giuseppe MERGE Matteo OSTERIA Giuseppe PACINI Lorenzo PALMA Francesco PALMONARI Federico PANICO Beatrice PATRIZII Laura PERFETTO Francesco PICOZZA Piergiorgio POZZATO Michele PUEL Matteo RASHEVSKAYA Irina RICCI Ester RICCI Marco RICCIARINI Sergio Bruno SCOTTI Valentina SOTGIU Alessando SPARVOLI Roberta SPATARO Bruno VITALE Vincenzo 《Science China(Technological Sciences)》 SCIE EI CAS CSCD 2018年第5期643-652,共10页
CSES(China Seismo-Electromagnetic Satellite) is a mission developed by CNSA(Chinese National Space Administration) and ASI(Italian Space Agency), to investigate the near-Earth electromagnetic, plasma and particle envi... CSES(China Seismo-Electromagnetic Satellite) is a mission developed by CNSA(Chinese National Space Administration) and ASI(Italian Space Agency), to investigate the near-Earth electromagnetic, plasma and particle environment, for studying the seismo-associated disturbances in the ionosphere-magnetosphere transition zone. The anthropogenic and electromagnetic noise,as well as the natural non-seismic electromagnetic emissions is mainly due to tropospheric activity. In particular, the mission aims to confirming the existence of possible temporal correlations between the occurrence of earthquakes for medium and strong magnitude and the observation in space of electromagnetic perturbations, plasma variations and precipitation of bursts with highenergy charged particles from the inner Van Allen belt. In this framework, the high energy particle detector(HEPD) of the CSES mission has been developed by the Italian LIMADOU Collaboration. HEPD is an advanced detector based on a tower of scintillators and a silicon tracker that provides good energy and angular resolution and a wide angular acceptance, for electrons of 3–100 Me V, protons of 30–200 Me V and light nuclei up to the oxygen. CSES satellite has been launched on February 2^(nd), 2018 from the Jiuquan Satellite Launch Center(China). 展开更多
关键词 earthquake seismic-precursors particle detector Van Allen belts magnetosphere ionosphere space weather cosmic rays
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A preliminary simulation study of influence of backsplash on the plastic scintillator detector design in HERD experiment 被引量:1
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作者 Peng Hu Zhi-gang Wang +14 位作者 Fabio Gargano Francesca Alemanno Corrado Altomare Tian-wei Bao Yong-wei Dong Valerio Formato Dimitrios Kyratzis Nicola Mori Lorenzo Pacini Zheng Quan Davide Serini Jun-jing Wang Rui-jie Wang Ming Xu Bo-bing Wu 《Radiation Detection Technology and Methods》 CSCD 2021年第3期332-338,共7页
Background The plastic scintillator detector(PSD)is one of the detectors in the high energy cosmic radiation detection(HERD)facility,which is designed for gamma-ray detection and a redundant charge measurement.Backspl... Background The plastic scintillator detector(PSD)is one of the detectors in the high energy cosmic radiation detection(HERD)facility,which is designed for gamma-ray detection and a redundant charge measurement.Backsplash will lead to a decrease in PSD’s performance of gamma-ray detection and charge measurement,which should be carefully considered.Purpose Two preliminary segmentation schemes of the PSD and two veto strategies have been proposed to suppress the backsplash effect.In this paper,we focus on the influence of the backsplash caused by gamma rays.The gamma-ray trigger efficiency and identification efficiency were studied in the case of different cell sizes and veto strategies,which can provide guidance on the PSD design.Methods A Monte Carlo simulation based on Geant4 has been performed.To simplify the simulation,the PSD is segmented into 1 cm3 cubes which can be easily aggregated into cells with different sizes during analysis.Results and conclusion Side_Veto can be used as a baseline design of veto strategy,whereas Smart_Veto can be selected as an upgraded design.Both the PSD bar cell with a width of less than 11 cm and the PSD tile cell with a width of less than 20 cm can achieve a sufficiently high gamma-ray trigger efficiency(>80%),which realizes the primary goal of the PSD.Meanwhile,both the PSD bar cell with a width of less than 3 cm and the PSD tile cell with a width of less than 20 cm can ensure a sufficiently high gamma-ray identification efficiency(>80%)for photons up to 800 GeV. 展开更多
关键词 Plastic scintillator detector Gamma-ray detection Backsplash VETO
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