Measurements of He isotopic ratio in cosmic rays in the 100 MeV – 1 GeV range with the PAMELA experiment M. Casolino1,2, C. De Santis1, N. De Simone1, V. Formato1, N. Nikonov1, P. Picozza1, and the PAMELA collaboration* 1INFN and Dept. of Physics, University of Rome Tor Vergata, Via Della Ricerca Scientifica 1, 00133, Rome, Italy 2RIKEN, Advanced Science Institute, Wako 351-0198, Japan *http://pamela.roma2.infn.it
Received: 15 Nov 2010 – Revised: 16 Feb 2011 – Accepted: 17 Feb 2011 – Published: 26 Oct 2011
Abstract. The PAMELA satellite-borne experiment was launched on 15 June 2006 from the Baikonur cosmodrome and it has been collecting data since then.
The apparatus comprises a time-of-flight system, a silicon-microstrip magnetic spectrometer, a silicon-tungsten electromagnetic calorimeter,
an anticoincidence system, a shower tail counter scintillator and a neutron detector. The combination of these devices allows precision studies
of the charged cosmic radiation to be conducted over a wide energy range (100 MeV – 1 TeV) with high statistics, with particular focus on the
antiparticle component. In this work we present 3He/4He isotopic ratio in the energy range from 100 MeV nucleon−1 to ~1 GeV nucleon−1.
The measured abundances are compared with different interstellar/heliospheric propagation calculations which are tuned on previous proton and helium
measurements.
Citation: Casolino, M., De Santis, C., De Simone, N., Formato, V., Nikonov, N., Picozza, P., and the PAMELA collaboration: Measurements of He isotopic ratio in cosmic rays in the 100 MeV – 1 GeV range with the PAMELA experiment, Astrophys. Space Sci. Trans., 7, 465-469, doi:10.5194/astra-7-465-2011, 2011.