Long-range acceleration induced by a scalar field external to gravity and the indication from Pioneer 10/11, Galileo and Ulysses Data

Abstract

We suggest an explanation of the "Pioneer effect" based on the interaction of the spacecraft with a long-range scalar field, $\varphi$. The scalar field under consideration is external to gravity, coupled to the ordinary matter and undergoes obedience to the weak equivalence principle. In the weak fields limit it result a long-range acceleration $a_P$, asymptotically constant within the region of the solar system hitherto crossed by the spacecraft.

Latex, 23 pages with 3 Postscript figures, submitted to Physical Review D