Further studies of the new component of cosmic rays at low energies

Recent observations using the GSFC-UNH cosmic ray telescope aboard the Pioneer 10 space probe have revealed an anomalous spectrum of nitrogen and oxygen nuclei relative to other nuclei such as carbon in the quiet time cosmic radiation below about 40 MeV/nuc. We have extended these observations with additional data from Pioneer 10 and considerable new data from an identical telescope aboard Pioneer 11. In addition to the enhancement of nitrogen and oxygen nuclei observed earlier we now observe the intensity of neon to be enhanced as well. The spectra of boron, magnesium and silicon appear to be similar to that of carbon. Within the accuracy of our measurements the enhancement factors for nitrogen, oxygen and neon are all approximately 10 relative to carbon at 10 MeV/nuc and the spectra of the enhanced nuclei can be represented by the form dj/dE approximately Esup(-2 x 6 +- 0.2) in the energy range 10-30 MeV/nuc. We will report details on the isotopic composition, solar modulation, and radial gradient of these nuclei. (orig.)