ToBeOrNotToBeThatIsThe?
From RHESSI Wiki
Line 9: | Line 9: | ||
|previous_nugget = [http://sprg.ssl.berkeley.edu/~tohban/wiki/index.php/Initiation_of_a_type_II_radio_burst_without_a_CME Initiation of a type II burst without a CME] | |previous_nugget = [http://sprg.ssl.berkeley.edu/~tohban/wiki/index.php/Initiation_of_a_type_II_radio_burst_without_a_CME Initiation of a type II burst without a CME] | ||
}} | }} | ||
+ | |||
+ | |||
+ | == Introduction == | ||
+ | |||
+ | Coronal mass ejections (CMEs) are often accompanied with activities low in the solar atmosphere including, e.g., extreme-ultraviolet (EUV) waves and coronal dimmings (see animated Fig. 1). The bright EUV waves (also known as EIT waves; see nugget 79) are large-scale disturbances propagating through the solar atmosphere most probably driven by the laterally expanding CME flanks. The dark dimming regions represent decreased emission in EUV and soft X-rays, most probably caused by the CME expansion, and are therefore interpreted as low-coronal footprints of CMEs (see e.g. nuggets 114 & 179). Two different types of dimming regions are observed: ''core'' or ''twin'' dimmings -- stationary, long-lived regions of strongly reduced EUV emission closely located to the eruption site covering opposite magnetic polarities. ''Secondary'' or ''remote'' dimmings -- more wide spread and less dark regions extending to significant distances away from the eruption site. As the corona is optically thin, bright as well as dark features represent intensities which are integrated along the line-of-sight (LOS). When viewed from single vantage points, EUV waves as well as dimming areas might severely suffer from projection effects, which makes their interpretation tricky. |
Revision as of 18:50, 10 August 2016
Nugget | |
---|---|
Number: | 28x |
1st Author: | Karin Dissauer |
2nd Author: | Manuela Temmer |
Published: | xx xxx 2016warning.pngThe date "xx xxx 2016" was not understood. |
Next Nugget: | xxxx |
Previous Nugget: | Initiation of a type II burst without a CME |
List all |
Introduction
Coronal mass ejections (CMEs) are often accompanied with activities low in the solar atmosphere including, e.g., extreme-ultraviolet (EUV) waves and coronal dimmings (see animated Fig. 1). The bright EUV waves (also known as EIT waves; see nugget 79) are large-scale disturbances propagating through the solar atmosphere most probably driven by the laterally expanding CME flanks. The dark dimming regions represent decreased emission in EUV and soft X-rays, most probably caused by the CME expansion, and are therefore interpreted as low-coronal footprints of CMEs (see e.g. nuggets 114 & 179). Two different types of dimming regions are observed: core or twin dimmings -- stationary, long-lived regions of strongly reduced EUV emission closely located to the eruption site covering opposite magnetic polarities. Secondary or remote dimmings -- more wide spread and less dark regions extending to significant distances away from the eruption site. As the corona is optically thin, bright as well as dark features represent intensities which are integrated along the line-of-sight (LOS). When viewed from single vantage points, EUV waves as well as dimming areas might severely suffer from projection effects, which makes their interpretation tricky.
RHESSI Nugget Date | warning.pngThe date "xx xxx 2016" was not understood. |
RHESSI Nugget First Author | Karin Dissauer + |
RHESSI Nugget Index | 28 x + |
RHESSI Nugget Second Author | Manuela Temmer + |