High Statistics Measurement of the Positron Fraction in Primary Cosmic Rays of 0.5-500 GeV with the Alpha Magnetic Spectrometer on the International Space Station
High Statistics Measurement of the Positron Fraction in Primary Cosmic Rays of 0.5-500 GeV with the Alpha Magnetic Spectrometer on the International Space Station
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DOI：
10.1103/physrevlett.113.121101
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发表时间：
2014-09-18
影响因子：
8.6
通讯作者：
Zurbach, C.
中科院分区：
文献类型：
--
作者：
Accardo, L.;Aguilar, M.;Zurbach, C.
本文介绍了利用AMS对能量范围从0.5到500 GeV的初级宇宙线中的正电子分数进行的精确测量，测量的基础是1090万个正电子和电子事件。这种测量扩展了我们以前观察到的能量范围，并提高了其精度。新的结果首次表明，在200 GeV以上，正电子分数不再随能量增加而增加。
A precision measurement by AMS of the positron fraction in primary cosmic rays in the energy range from 0.5 to 500 GeV based on 10.9 million positron and electron events is presented. This measurement extends the energy range of our previous observation and increases its precision. The new results show, for the first time, that above similar to 200 GeV the positron fraction no longer exhibits an increase with energy.