Intermittency and q-Gaussian Distributions in the Magnetic Field of the Very Local Interstellar Medium (VLISM) Observed by Voyager 1 and Voyager 2

Abstract

Voyager 1 (V1) observed q-Gaussian distributions of 1 hr increments of the components the magnetic field ${\boldsymbol{B}}$ throughout the very local interstellar medium (VLISM) on scales on the order of 1 year, from 2013 through 2019, excluding the disturbed regions near two shocks. The intermittency of the components of B is described by q from the q-Gaussian distributions of 1 hr increments B as well as by the kurtosis K derived from the time series of the increments of ${\boldsymbol{B}}$. Farther than ~5 au from the heliopause, Voyager 1 observed larger intermittency in the fluctuations of the predominantly transverse component B N and in the nearly longitudinal component B T of ${\boldsymbol{B}}$. The average values of q for the B N component and transverse B T component for these data in the VLISM are q = 1.32 ± 0.03 and q = 1.22 ± 0.03, respectively. The corresponding average values of the kurtosis are K = 7.2 and K = 4.9. Voyager 2 (V2) crossed the heliopause on 2018 November 5. Near the heliopause, in 2019, V2 observed large intermittency in 1 hr increments of the compressive component B T and smaller intermittency in B N. The Voyager 2 observations give q = 1.51 ± 0.06 and q = 1.17 ± 0.06 for the B N and B T components of B, respectively, as well as K = 7.2 and K = 12.3, respectively. The intermittency in B T and B N, observed by V2 near the heliopause was significantly larger than that observed by V1 when it was near the heliopause.