English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Plus monthly

Global: Zendy Tools annual

Global: Zendy Tools monthly

Global: Zendy Free Plan

The origin of cosmic rays above the knee in the spectrum is an unsolvedproblem. We present a wind model in which interstellar gas flows along anon-rotating, expanding flux tube with a changing speed and cross-sectionalarea. Cosmic rays from Galactic sources, such as supernova remnants, which arecoupled to the plasma via Alfv\'{e}n waves, provide the main pressure sourcefor driving this outflow. These cosmic rays are then subject to diffusive shockreacceleration at the Galactic wind termination shock, which is located at adistance $\sim200\,{\rm kpc}$. Some of the highest-energy reacceleratedparticles propagate upstream against the wind and can contribute to the PeV-EeVrange of the spectrum. We analyze the conditions under which efficientreacceleration can occur and find that rigidities $\sim$ 10-40 PV can beobtained and that the termination shock may account for half of the protonspectrum measured in IceCube/IceTop experiment. The highest-energy particlesthat escape downstream from our termination shock, and similar shockssurrounding most galaxies, can be further accelerated by intergalactic shockfronts.

Reacceleration of Galactic Cosmic Rays Beyond the Knee at the Termination Shock of a Cosmic-Ray-Driven Galactic Wind