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 Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

It is known that the ionospheric cross polar cap potential (CPCP)saturates when the interplanetary magnetic field (IMF) Bz becomesvery large. Few studies have offered physical explanations as to whythe polar cap potential saturates. We present 13 events in which thereconnection electric field (REF) goes above 12mV/m at some time.When these events are examined as typically done in previous studies,all of them show some signs of saturation (i.e., over-prediction ofthe CPCP based on a linear relationship between the IMF and the CPCP).We show that by taking into account the size of the magnetosphere andthe fact that the post-shock magnetic field strength is stronglydependent upon the solar wind Mach number, we can better specify theionospheric CPCP. The CPCP (Φ) can be expressed as Φ=(10-4v2+11.7B(1-e-Ma/3)sin3(θ/2)) {rms/9 (wherev is the solar wind velocity, B is the combined Y and Zcomponents of the interplanetary magnetic field, Ma is the solarwind Mach number, θ=acos(Bz/B), and rms is the stand-offdistance to the magnetopause, assuming pressure-balance between thesolar wind and the magnetosphere). This is a simple modification ofthe original Boyle et al. (1997) formulation

A new formulation for the ionospheric cross polar cap potential including saturation effects