1203.6112 (N. Tomassetti)

AMS Observations of Light Cosmic Ray Isotopes and Implications for their
Production in the Galaxy    [PDF]

N. Tomassetti

Observations of light isotopes in cosmic rays provide information on their origin and propagation in the Galaxy. Using the data collected by AMS-01 in the STS- 91 space mission, we compare the measurements on 1H, 2H, 3He and 4He with calculations for interstellar propagation and solar modulation. These data are described well by a diffusive-reacceleration model with parameters that match the B/C ratio data. Close comparisons are made within the astrophysical con- straints provided by the B/C data and within the nuclear uncertainties arising from the production cross sections. Astrophysical uncertainties are expected to be dramatically reduced by future data, but nuclear uncertainties may rep- resent a serious limitation of the model predictions. A diagnostic test for the reliability of the models is given by ratios such as 2H/3He, 6Li/7Li or 10B/11B.

View original: http://arxiv.org/abs/1203.6112