Radial Evolution of Sunward Strahl Electrons in the Inner Heliosphere

Result code in IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F68378289%3A_____%2F20%3A00536256" target="_blank" >RIV/68378289:_____/20:00536256 - isvavai.cz</a>

Result on the web

<a href="https://doi.org/10.1007/s11207-019-1579-3" target="_blank" >https://doi.org/10.1007/s11207-019-1579-3</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1007/s11207-019-1579-3" target="_blank" >10.1007/s11207-019-1579-3</a>

Result language

angličtina

Original language name

Radial Evolution of Sunward Strahl Electrons in the Inner Heliosphere

Original language description

The heliospheric magnetic field (HMF) exhibits local inversions, in which the field apparently ´bends back´ upon itself. Candidate mechanisms to produce these inversions include various configurations of upstream interchange reconnection: either in the heliosphere, or in the corona where the solar wind is formed. Explaining the source of these inversions, and how they evolve in time and space, is thus an important step towards explaining the origins of the solar wind. Inverted heliospheric magnetic field lines can be identified by the anomalous sunward (i.e. inward) streaming of the typically anti-sunward propagating, field-aligned (or anti-aligned), beam of electrons known as the ´strahl´. We test if the pitch angle distribution (PAD) properties of sunward-propagating strahl are different from those of outward strahl. We perform a statistical study of strahl observed by the Helios spacecraft, over heliocentric distances spanning approximate to 0.3 - 1 AU. We find that sunward strahl PADs are broader and less intense than their outward directed counterparts: particularly at distances 0.3 - 0.75 AU. This is consistent with sunward strahl being subject to additional, path-length dependent, scattering in comparison to outward strahl. We conclude that the longer and more variable path from the Sun to the spacecraft, along inverted magnetic field, leads to this additional scattering. The results also suggest that the relative importance of scattering along this additional path length drops off with heliocentric distance. These results can be explained by a relatively simple, constant-rate, scattering process.

Czech name

—

Czech description

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Type

J_imp - Article in a specialist periodical, which is included in the Web of Science database

CEP classification

—

OECD FORD branch

10308 - Astronomy (including astrophysics,space science)

Project

—

Continuities

I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace

Publication year

2020

Confidentiality

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Name of the periodical

Solar Physics

ISSN

0038-0938

e-ISSN

—

Volume of the periodical

295

Issue of the periodical within the volume

2

Country of publishing house

NL - THE KINGDOM OF THE NETHERLANDS

Number of pages

26

Pages from-to

16

UT code for WoS article

000519632300003

EID of the result in the Scopus database

2-s2.0-85078285010