Aug 7 – 11, 2017
Columbus, Ohio, USA
US/Eastern timezone

Precision Measurement of 3He-to-4He ratio in Cosmic Rays with the Alpha Magnetic Spectrometer on the International Space Station

Aug 9, 2017, 2:00 PM
Macedonian Room (The Athenaeum)

Macedonian Room

The Athenaeum

Oral Cosmic rays Cosmic rays


Dr Francesca Giovacchini (CIEMAT (SPAIN))


Knowledge of the energy dependence of the 3He-to-4He flux ratio (3He/4He) is important in understanding the propagation of cosmic rays. As 3He is assumed to be produced by interactions of heavier nuclei with the interstellar matter, the 3He/4He ratio is a powerful tool for determining the amount of interstellar material traversed by cosmic rays. AMS results are based on 9 million 3He events and 56 million 4He events collected in the first five years of operation onboard the ISS. The precise measurement of the 3He/4He ratio from 0.7 GeV/n to 10GeV/n is presented for the first time. The AMS results are unique and distinct from all the previous data.

Primary authors

Dr Carlos Delgado (CIEMAT) Dr Francesca Giovacchini (CIEMAT (SPAIN)) Mr Matthew Behlmann (MIT) Prof. Paolo Zuccon (MIT)

Presentation materials