γ暴高能辐射的研究一直是天体物理和宇宙线物理的研究热点,但在100 Ge V及以上能区至今尚未获得确定的观测结果。位于西藏羊八井宇宙线观测站(海拔4 300 m)的ARGO-YBJ实验具有高海拔、大视场等特点,其阈能约几百个Ge V,在探测高能γ暴...γ暴高能辐射的研究一直是天体物理和宇宙线物理的研究热点,但在100 Ge V及以上能区至今尚未获得确定的观测结果。位于西藏羊八井宇宙线观测站(海拔4 300 m)的ARGO-YBJ实验具有高海拔、大视场等特点,其阈能约几百个Ge V,在探测高能γ暴方面具有独特的优势。利用ARGO-YBJ实验中的"双前峰面"事例,可降低探测器的阈能达几十个Ge V,提高实验探测γ暴的灵敏度。作者研究了ARGO-YBJ实验中的"双前峰面"事例,并通过Monte Carlo模拟,估算出利用该类事例探测高能区(10—100 Ge V)γ暴所需要的最低能流为10-4—10-3erg.cm^(-2)。展开更多
ARGO-YBJ, located at the Yangbajing Cosmic Ray Observatory （4300 m a.s.l., Tibet, China）, is a full coverage air shower array, with an energy threshold of -300 GeV for gamma-ray astronomy. Most of the recorded event...ARGO-YBJ, located at the Yangbajing Cosmic Ray Observatory （4300 m a.s.l., Tibet, China）, is a full coverage air shower array, with an energy threshold of -300 GeV for gamma-ray astronomy. Most of the recorded events are single front showers, satisfying the trigger requirement of at least 20 particles detected in a given time window. However, in -11.5% of the events, two randomly arriving showers may be recorded in the same time window, and the second one, generally smaller, does not need to satisfy the trigger condition. These events are called double shower front events. By using these small showers, well under the trigger threshold, the detector primary energy threshold can be lowered to a few tens of GeV. In this paper, the angular resolution that can be achieved with these events is evaluated by a full Monte Carlo simulation. The ARGO-YBJ sensitivity in detecting gamma-ray bursts （GRBs） by using double shower front events is also studied for various cutoff energies, time durations, and zenith angles of GRBs in ARGO＇s field of view.展开更多
The National Natural Science Foundation of China (NSFC) has approved the major Sino-Italian international cooperative research project "YangBa Jing Full Coverage AS Array and Cosmic Ray
逾20年的策划,数十人十多年的埋头苦干,迎来了羊八井宇宙线实验大发展历史机遇的到来。作为中科院规划中的国家西部基础研究平台,羊八井的学科定位、平台功能、近远期目标和科研项目,须在对学科发展、国家需要、羊八井优势和现有基础的...逾20年的策划,数十人十多年的埋头苦干,迎来了羊八井宇宙线实验大发展历史机遇的到来。作为中科院规划中的国家西部基础研究平台,羊八井的学科定位、平台功能、近远期目标和科研项目,须在对学科发展、国家需要、羊八井优势和现有基础的清楚认识的基础上加以规划。作为一个基础研究平台,羊八井需要一个功能强大、能覆盖广阔能区、能支持多个课题甚至能为多种学科长期服务的当家设备。为此,许多建议被提了出来,展现了人们从不同角度对羊八井发展的设计。文章对此作了简要评论并具体提出了“基于AR G O地毯的羊八井超级复合陈列计划”及发展多学科研究、明确平台功能和理顺管理体制等诸项建议。展开更多
The muonic component of the extensive air showers (EAS) is of great importance for the astroparticle physics. It carries the information about the properties of primary cosmic ray (CR) particles, such as their mass, a...The muonic component of the extensive air showers (EAS) is of great importance for the astroparticle physics. It carries the information about the properties of primary cosmic ray (CR) particles, such as their mass, and electromagnetic and hadronic nature. It provides a sensitive test for the hadronic interaction models, which are inevitable for describing the cascade shower development of cosmic rays in EAS experiments. The YangBaJing Hybrid Array (YBJ-HA) experiment has been in operation since the end of 2016. Surface detectors are used for the measurements of primary energy, angular direction and core position of a shower event, while underground muon detectors are used for measuring the density of muons at various locations. Using the data obtained by the YBJ-HA experiment,this work reports the first measurement of the lateral muon distribution for the primary cosmic ray energy in the 100TeV region. The punch-through effect is evaluated via MC simulation.展开更多
The energy spectrum of cosmic Hydrogen and Helium nuclei has been measured below the so-called ＂knee＂ by using a hybrid experiment with a wide field-of-view Cherenkov telescope and the Resistive Plate Chamber （RPC...The energy spectrum of cosmic Hydrogen and Helium nuclei has been measured below the so-called ＂knee＂ by using a hybrid experiment with a wide field-of-view Cherenkov telescope and the Resistive Plate Chamber （RPC） array of the ARGO-YBJ experiment at 4300 m above sea level. The Hydrogen and Helium nuclei have been well separated from other cosmic ray components by using a multi-parameter technique. A highly uniform energy resolution of about 25% is achieved throughout the whole energy range （100-700 TeV）. The observed energy spectrum is compatible with a single power law with index γ=-2.63±0.06.展开更多
文摘γ暴高能辐射的研究一直是天体物理和宇宙线物理的研究热点,但在100 Ge V及以上能区至今尚未获得确定的观测结果。位于西藏羊八井宇宙线观测站(海拔4 300 m)的ARGO-YBJ实验具有高海拔、大视场等特点,其阈能约几百个Ge V,在探测高能γ暴方面具有独特的优势。利用ARGO-YBJ实验中的"双前峰面"事例,可降低探测器的阈能达几十个Ge V,提高实验探测γ暴的灵敏度。作者研究了ARGO-YBJ实验中的"双前峰面"事例,并通过Monte Carlo模拟,估算出利用该类事例探测高能区(10—100 Ge V)γ暴所需要的最低能流为10-4—10-3erg.cm^(-2)。
基金Supported by National Natural Science Foundation of China(11475141)Fundamental Research Funds for Central Universities(2682014CX091)
文摘ARGO-YBJ, located at the Yangbajing Cosmic Ray Observatory （4300 m a.s.l., Tibet, China）, is a full coverage air shower array, with an energy threshold of -300 GeV for gamma-ray astronomy. Most of the recorded events are single front showers, satisfying the trigger requirement of at least 20 particles detected in a given time window. However, in -11.5% of the events, two randomly arriving showers may be recorded in the same time window, and the second one, generally smaller, does not need to satisfy the trigger condition. These events are called double shower front events. By using these small showers, well under the trigger threshold, the detector primary energy threshold can be lowered to a few tens of GeV. In this paper, the angular resolution that can be achieved with these events is evaluated by a full Monte Carlo simulation. The ARGO-YBJ sensitivity in detecting gamma-ray bursts （GRBs） by using double shower front events is also studied for various cutoff energies, time durations, and zenith angles of GRBs in ARGO＇s field of view.
文摘The National Natural Science Foundation of China (NSFC) has approved the major Sino-Italian international cooperative research project "YangBa Jing Full Coverage AS Array and Cosmic Ray
文摘逾20年的策划,数十人十多年的埋头苦干,迎来了羊八井宇宙线实验大发展历史机遇的到来。作为中科院规划中的国家西部基础研究平台,羊八井的学科定位、平台功能、近远期目标和科研项目,须在对学科发展、国家需要、羊八井优势和现有基础的清楚认识的基础上加以规划。作为一个基础研究平台,羊八井需要一个功能强大、能覆盖广阔能区、能支持多个课题甚至能为多种学科长期服务的当家设备。为此,许多建议被提了出来,展现了人们从不同角度对羊八井发展的设计。文章对此作了简要评论并具体提出了“基于AR G O地毯的羊八井超级复合陈列计划”及发展多学科研究、明确平台功能和理顺管理体制等诸项建议。
基金Supported by National Key R&D Program of China(2018YFA0404202)National Natural Science Foundation of China(11635011,11761141001,11765019,11775233)
文摘The muonic component of the extensive air showers (EAS) is of great importance for the astroparticle physics. It carries the information about the properties of primary cosmic ray (CR) particles, such as their mass, and electromagnetic and hadronic nature. It provides a sensitive test for the hadronic interaction models, which are inevitable for describing the cascade shower development of cosmic rays in EAS experiments. The YangBaJing Hybrid Array (YBJ-HA) experiment has been in operation since the end of 2016. Surface detectors are used for the measurements of primary energy, angular direction and core position of a shower event, while underground muon detectors are used for measuring the density of muons at various locations. Using the data obtained by the YBJ-HA experiment,this work reports the first measurement of the lateral muon distribution for the primary cosmic ray energy in the 100TeV region. The punch-through effect is evaluated via MC simulation.
基金Supported by NSFC(10975145,11075170)Knowledge Innovation Fund(H85451D0U2)of IHEP+2 种基金Chinese Ministry of Science and Technology,Chinese Academy of Science,Key Laboratory of Particle Astrophysics,CASin Italy by the Istituto Nazionale di Fisica Nucleare(INFN)Ministero dell’Istruzione,dell’Università e della Ricerca(MIUR)
文摘The energy spectrum of cosmic Hydrogen and Helium nuclei has been measured below the so-called ＂knee＂ by using a hybrid experiment with a wide field-of-view Cherenkov telescope and the Resistive Plate Chamber （RPC） array of the ARGO-YBJ experiment at 4300 m above sea level. The Hydrogen and Helium nuclei have been well separated from other cosmic ray components by using a multi-parameter technique. A highly uniform energy resolution of about 25% is achieved throughout the whole energy range （100-700 TeV）. The observed energy spectrum is compatible with a single power law with index γ=-2.63±0.06.
