报告题目:On the Contribution of "Fresh" Cosmic Rays to the Excesses of Secondary Particles
报 告 人:郭义庆(中国科学院高能物理研究所)
报告摘要:The standard model of cosmic ray propagation has been very successful in explaining all kinds of the Galactic cosmic ray spectra. However, high precision measurement recently revealed the appreciable discrepancy between data and model expectation, from spectrum observations of gamma-rays, e^+/e^and probably the B/C ratio starting from ~10 GeV energy.In this work, we propose that the fresh cosmic rays, which are supplied by the young accelerators and detained by local magnetic field, can contribute additional secondary particles interacting with local materials. As this early cosmic ray has a hard spectrum, the model calculation results in a two-component gammaray spectrum, which agree very well with the observation. Simultaneously, the expected neutrino number from the galactic plane could contribute ~60% of IceCube observed neutrino number below a few hundreds of TeV. The same pp-collision process can account for a significant amount of the positron excesses. Under this model, it is expected that the excesses in anti-p/pand B/C ratio will show up when energy is above ~10 GeV. We look forward that the model will be tested in the near future by new observations from AMS02, IceCube, ASg, HAWC and future experiments such as LHASSO, HiSCORE and CTA.
时 间:1月29日星期四上午10:00
地 点:紫金山天文台517会议室
联 系 人:朱林林(83332173)
欢迎大家积极参加!
紫金山天文台学术委员会