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

Extreme ultraviolet (EUV) coronal dimmings are often observed in response tosolar eruptive events. These phenomena can be generated via several differentphysical processes. For space weather, the most important of these is thetemporary void left behind by a coronal mass ejection (CME). Massive, fast CMEstend to leave behind a darker void that also usually corresponds to minimumirradiance for the cooler coronal emissions. If the dimming is associated witha solar flare, as is often the case, the flare component of the irradiancelight curve in the cooler coronal emission can be isolated and removed usingsimultaneous measurements of warmer coronal lines. We apply this technique to37 dimming events identified during two separate two-week periods in 2011, plusan event on 2010 August 7 analyzed in a previous paper, to parameterize dimmingin terms of depth and slope. We provide statistics on which combination ofwavelengths worked best for the flare-removal method, describe the fittingmethods applied to the dimming light curves, and compare the dimming parameterswith corresponding CME parameters of mass and speed. The best linearrelationships found are  $$ \begin{align} v_{CME} \Big[\frac{km}{s} \Big] & \approx 2.36 \times 10^6\Big[\frac{km}{\%} \Big] \times s_{dim} \Big[\frac{\%}{s} \Big] \\ m_{CME} [g]& \approx 2.59 \times 10^{15} \Big[\frac{g}{\%} \Big] \times \sqrt{d_{dim}}[\%]. \end{align} $$  These relationships could be used for space weather operations of estimatingCME mass and speed using near-realtime irradiance dimming measurements.

Relationship of EUV Irradiance Coronal Dimming Slope and Depth to Coronal Mass Ejection Speed and Mass