No Stagnation Region Before the Heliopause at Voyager 1? Inferences From New Voyager 2 Results. (arXiv:2011.12926v1 [astro-ph.HE])

No Stagnation Region Before the Heliopause at Voyager 1? Inferences From New Voyager 2 Results. (arXiv:2011.12926v1 [astro-ph.HE])
<a href="http://arxiv.org/find/astro-ph/1/au:+Cummings_A/0/1/0/all/0/1">A. C. Cummings</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Stone_E/0/1/0/all/0/1">E. C. Stone</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Richardson_J/0/1/0/all/0/1">J. D. Richardson</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Heikkila_B/0/1/0/all/0/1">B. C. Heikkila</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Lal_N/0/1/0/all/0/1">N. Lal</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Kota_J/0/1/0/all/0/1">J. K&#xf3;ta</a>

We present anisotropy results for anomalous cosmic-ray (ACR) protons in the
energy range $sim$0.5-35 MeV from Cosmic Ray Subsytem (CRS) data collected
during calibration roll maneuvers for the magnetometer instrument when Voyager
2 (V2) was in the inner heliosheath. We use a new technique to derive for the
first time the radial component of the anisotropy vector from CRS data. We find
that the CRS-derived radial solar wind speeds, when converted from the radial
components of the anisotropy vectors via the Compton-Getting (C-G) effect,
generally agree with those similarly-derived speeds from the Low-Energy Charged
Particle experiment using 28-43 keV data. However, they often differ
significantly from the radial solar wind speeds measured directly by the Plasma
Science (PLS) instrument. There are both periods when the C-G-derived radial
solar wind speeds are significantly higher than those measured by PLS and times
when they are significantly lower. The differences are not expected nor
explained, but it appears that after a few years in the heliosheath the V2
radial solar wind speeds derived from the C-G method underestimate the true
speeds as the spacecraft approaches the heliopause. We discuss the implications
of this observation for the stagnation region reported along the Voyager 1
trajectory as it approached the heliopause inferred using the C-G method.

We present anisotropy results for anomalous cosmic-ray (ACR) protons in the
energy range $sim$0.5-35 MeV from Cosmic Ray Subsytem (CRS) data collected
during calibration roll maneuvers for the magnetometer instrument when Voyager
2 (V2) was in the inner heliosheath. We use a new technique to derive for the
first time the radial component of the anisotropy vector from CRS data. We find
that the CRS-derived radial solar wind speeds, when converted from the radial
components of the anisotropy vectors via the Compton-Getting (C-G) effect,
generally agree with those similarly-derived speeds from the Low-Energy Charged
Particle experiment using 28-43 keV data. However, they often differ
significantly from the radial solar wind speeds measured directly by the Plasma
Science (PLS) instrument. There are both periods when the C-G-derived radial
solar wind speeds are significantly higher than those measured by PLS and times
when they are significantly lower. The differences are not expected nor
explained, but it appears that after a few years in the heliosheath the V2
radial solar wind speeds derived from the C-G method underestimate the true
speeds as the spacecraft approaches the heliopause. We discuss the implications
of this observation for the stagnation region reported along the Voyager 1
trajectory as it approached the heliopause inferred using the C-G method.

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