Frank B. McDonald

Senior Research Scientist,
Member of the National Academy of Sciences
Cosmic Ray Astrophysics

The current research of Frank McDonald and his associates is directed toward understanding the properties of the galactic cosmic radiation, its transport in the interstellar medium and its modulation by our own heliosphere; the acceleration and transport of solar/interplanetary energetic particles and the study of the dynamics of the outer heliosphere_one of the last unexplored regions of our solar system. This research makes extensive use of the energetic particle data from Pioneer 10 and 11 on which Dr. McDonald is P. I. for one of the cosmic ray experiments and the Voyager cosmic ray experiment for which he is a co-investigator. These four experiments continue to provide exceptional data with excellent charge, mass and energy resolution for galactic cosmic rays and a host of other energetic particle components in the outer heliosphere. Use is also made of data from various spacecraft near 1 AU. The focus of these studies is to understand the basic acceleration and transport processes of these different energetic particle populations. There is an active collaboration with the interplanetary magnetic fields and plasma experiments on the Pioneer and Voyager missions and with colleagues here at Maryland and the Goddard Space Flight Center, as well as with laboratories at New Mexico State University; Potchefstroom University, South Africa; Nagoya University, Japan; and the Service d'Astrophysique, CERN-Saclay, France. We are also starting a new program to study the acceleration and propagation of high energy solar energetic particles. Selected publications:

Selected publications:

1. Global Merged Interaction Regions in the Outer Heliosphere, F.B. McDonald and L.F. Burlaga, p. 389 (J.R. Jokipii, C.P. Sonnett and S. Giampapaeds.) (Cosmic Winds and the Heliosphere, The University of Arizona Press,Tucson, 1997).
2. Cosmic Ray Modulation in the Heliosphere_ A Phenomenological Study, F.B. McDonald, Space Science Reviews, 83, 33, 1998. A Comparative Study of Cosmic Ray Radial and Latitudinal Gradients in the Inner and Outer Heliosphere, F.B. McDonald, P. Ferrando, B. Heber, et al., Journal of Geophysical Research, 102, p. 4643, 1997.