Measurements Of Cosmic-ray Nuclei Research Articles

First measurements of cosmic-ray nuclei at high energy with CREAM

The balloon-borne cosmic-ray experiment CREAM-I (Cosmic-Ray Energetics And Mass) recently completed a successful 42-day flight during the 2004–2005 NASA/NSF/NSBF Antarctic expedition. CREAM-I combines an imaging calorimeter with charge detectors and a precision transition radiation detector (TRD). The TRD component of CREAM-I is targeted at measuring the energy of cosmic-ray particles with charges greater than Z ∼ 3. A central science goal of this effort is the determination of the ratio of secondary to primary nuclei at high energy. This measurement is crucial for the reconstruction of the propagation history of cosmic rays, and consequently for the determination of their source spectra. First scientific results from this instrument are presented.

Measurements of cosmic ray nuclei with energies of some hundred MeV/nucleon in the LDEF mission

As a contribution to the FREE FLYER BIOSTACK EXPERIMENT (A0015) we have flown CR-39 plastic nuclear track detectors on board LDEF. Although low energy fully-ionized galactic cosmic rays should not reach this orbit due to geomagnetic shielding we found stopping nuclei with energies of some hundred MeV/nucleon. Directions of incidence, nuclear charge and energy spectra of these particles are presented and discussed.