A Magnetic Pressure Front Upstream of the Heliopause and the Heliosheath Magnetic Fields and Plasma, Observed during 2017
Loading...
Links to Files
Author/Creator ORCID
Date
2019-05-21
Type of Work
Department
Program
Citation of Original Publication
L. F. Burlaga, et.al, A Magnetic Pressure Front Upstream of the Heliopause and the Heliosheath Magnetic Fields and Plasma, Observed during 2017, The Astrophysical Journal, Volume 877, Number 1, https://doi.org/10.3847/1538-4357/ab16f1
Rights
This item is likely protected under Title 17 of the U.S. Copyright Law. Unless on a Creative Commons license, for uses protected by Copyright Law, contact the copyright holder or the author.
© 2019 The American Astrophysical Journal
© 2019 The American Astrophysical Journal
Abstract
Voyager 1 (V1), moving in the interstellar magnetic field, observed an increase in the daily averages of B beginning
on day ≈346, 2016, rising to a local maximum on day ≈382, and declining nearly monotonically for the most part
until day 720, measured from 2016.0. A pressure front was observed during a ≈35-day interval beginning on day
346, 2016. The pressure front observed by V1 was not a shock, although one might expect it to evolve into a shock.
Voyager 2 (V2) observed the distant heliosheath during 2017. The average B in the heliosheath was relatively high,
0.130 nT. The distribution of azimuthal angles had two nearly equal maxima at approximately 90° and 180°. An
unusual transition of the BT component from a large “away” sector to a large “toward” sector occurred during 2017
from day 101 to day 239. Abrupt but small changes in magnetic polarity occurred between day 146 and day 239,
when the average BT component of B was close to zero. Changes in the >70 MeV nucleon−1 cosmic-ray intensity
were qualitatively related to the B(t) profile described by the CR-B relationship. There was no net decrease in
magnetic flux at V2 in the heliosheath during 2017 that might be attributed to ongoing magnetic reconnection in the
heliosheath. Small-scale increments in B can be described by a q-Gaussian distribution with q = 1.64 ± 0.02 for
hourly averages of B and q = 1.54 ± 0.08 for daily averages of B.