SEARCH FOR VERY HIGH ENERGY GAMMA-RAYS FROMACTIVE GALACTIC NUCLEI

寻找来自活动星系核的极高能量伽玛射线

• 批准号: 12640292
• 负责人: NISHIJIMA Kyoshi
• 金额: $ 1.15万
• 依托单位: TOKAI UNIVERSITY
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 2000
• 资助国家: 日本
• 起止时间: 2000 至 2001
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-12640292/
• 关键词: gamma-rays; active galactic nuclei; air Cherenkov telescope; CANGAROO; PKS2005-49; PKS2155-304; Mrk421; extragalactic infrared photon; PKS2005-489; PKS2155-304; PKS2155^304; PKS0548-322

Observation of AGNs : I have observed four AGNs in the energy range above several hundred GeV using CANGAROO-II 10 m telescope. For PKS2155-304, observation has been done for about 36 hours for on-source scan and about 35 hours for off-source scan including participation in the mulriwave length campaign. I have seen no evidence for persistent gamma-ray emission from PKS2155-304. Flux upper limits(2δ)is obtained to be 1.2×10^<-11>cm^<-2> sec^<-1> for above 400GeV.PKS2005-489 was observed for 33 hours for on-source scan and 31 hours for off-source scan. RXTE observation were carried out for 15 days during my observation periods in 2000. I have seen no evidence for persistent gamma-ray emission from PKS2005-489. Flux upper limit(2δ) obtained for above 450 GeV is 6.4×10^<-12> cm^<-2> sec^<-1>. During my observation periods, both targets remained in a low level state. We observed Mrk421 for ten nights during its active state in early 2001 using the very large zenith angle technique. The result shows the detection of gamma-rays from Mrk421 in the energy range above 10 TeV. Considering the absorption by extragalactic infrared photons, this implies that the energy spectrum in a high level state is very hard.Development of trigger module : In order to lower the energy threshold, I studied the trigger condition by the Monte Carlo simulation, and I found clustering trigger is very effective. Then I develop the intelligent trigger module using complimentary programmable logic device to realize the clustering trigger.

活动星系核的观测：我用CanGaroo-II 10米望远镜观测到了四个能量范围在几百GeV以上的活动星系核。对于PKS2155-304，源上扫描已观察约36小时，源外扫描约35小时，包括参与多波长运动。我没有看到PKS2155-304持续发射伽马射线的证据。对于400GeV以上，获得的通量上限(2δ)为1.2×10；；-11；cm；-2；秒；-1；-1；对于源扫描，PKS2005-489观察了33小时，离源扫描为31小时。在我2000年的观察期内进行了为期15天的RXTE观察。我没有看到PKS2005-489持续伽马射线发射的证据。在450GeV以上获得的磁通上限(2δ)为6.4×10；-12；cm；-2。在我的观察期间，这两个目标都保持在低水平状态。2001年初，我们利用极大天顶角技术，在其活跃态期间对MRK421进行了10个晚上的观测。结果表明，在10TeV以上的能量范围内，探测到了MRK421的伽马射线。触发模块的开发：为了降低能量阈值，通过蒙特卡罗模拟对触发条件进行了研究，发现聚簇触发是非常有效的。然后利用配套的可编程逻辑器件开发了智能触发模块，实现了集群式触发。

项目成果

Kyoshi Nishijima: "Very High Energy Gamma-Ray Observations of AGNs with CANGAROO"Publication of the Astronomical Society of Australia. 19(in press). (2002)

Kyoshi Nishijima：“用 CANGAROO 对活动星系核进行甚高能伽马射线观测”澳大利亚天文学会出版物。

Kyoshi Nishijima: "Very High Energy Gamma-Ray Observations of AGNs with CANGAROO"Publication of the Astronomical Society of Australia. 19. 26-28 (2002)

Kyoshi Nishijima：“用 CANGAROO 对活动星系核进行甚高能伽马射线观测”澳大利亚天文学会出版物。

K. Nishijima: "Very High Energy Gamma-Ray Obervation of AGNs with CANGAROO"Publication of the Astronomical Society of Australia. 19. 26-28 (2002)

K. Nishijima：“用 CANGAROO 对 AGN 进行甚高能伽马射线观测”澳大利亚天文学会出版物。