Status Report

High Statistics Measurement of the Positron Fraction in Primary Cosmic Rays with the Alpha Magnetic Spectrometer on the International Space Station

By SpaceRef Editor
January 2, 2017
Filed under , , ,

Sami Caroff (for the AMS-02 collaboration)
(Submitted on 30 Dec 2016)

A precision measurement by AMS-02 of the positron fraction in primary cosmic rays is presented on this proceeding. Over the last two decades, there has been a strong interest in the cosmic ray positron fraction which exhibit an excess of high energy positrons whose origin is still highly uncertain. The Alpha Magnetic Spectrometer (AMS-02) is a general purpose high-energy particle physics detector operational on the International Space Station since May 2011. During its unique long duration mission AMS-02 is collecting large amount of data to study the behavior of cosmic ray electrons and positrons with unprecedented precision. This measurement shows that the positron fraction exhibit a rapid decrease from 1 to 8 GeV followed by a steady increase. We show that above 275 GeV the positron fraction no longer exhibits an increase with energy.

Comments:    XXV ECRS 2016 Proceedings – eConf C16-09-04.3
Subjects:    High Energy Astrophysical Phenomena (astro-ph.HE)
Cite as:    arXiv:1612.09579 [astro-ph.HE] (or arXiv:1612.09579v1 [astro-ph.HE] for this version)
Submission history
From: Sami Caroff
[v1] Fri, 30 Dec 2016 20:04:45 GMT (263kb,D)

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