E-Print Archive

There are 4291 abstracts currently viewable.


Advanced Search
Main Page Add New E-Print Submitter
News Help/FAQ About Preferences
Manage Key Phrase
* News 04/04/20 * The archive is using a new backend database. This has thrown up a few SQL errors in the last few days. If you have any issues please email adavey@nso.edu with either the number of eprint you are trying to edit or a link to your preprint.

Measuring and modeling the rate of separator reconnection between an emerging and existing active region  

Marika Isabel McCarthy   Submitted: 2019-11-18 10:54

Magnetic reconnection occurs when new flux emerges into the corona and becomes incorporated into the existing coronal field. A new active region (AR) emerging in the vicinity of an existing AR provides a convenient laboratory in which reconnection of this kind can be quantified. We use high time-cadence 171 Å data from SDO/AIA focused on new/old active region pair 11147/11149, to quantify reconnection. We identify new loops as brightenings within a strip of pixels between the regions. This strategy is premised on the assumption that the energy brightening a loop originates in magnetic reconnection. We catalog 301 loops observed in the 48-hour time period beginning with the emergence of AR 11149. The rate at which these loops appear between the two ARs is used to calculate the reconnection rate between them. We then fit these loops with magnetic field, solving for each loop's field strength, geometry, and twist (via its proxy, coronal α ). We find the rate of newly-brightened flux overestimates the flux which could be undergoing reconnection. This excess can be explained by our finding that the interconnecting region is not at its lowest energy (constant- α ) state; the extrapolations exhibit loop-to-loop variation in α . This flux overestimate may result from the slow emergence of AR 11149, allowing time for Taylor relaxation internal to the domain of the reconnected flux to bring the α distribution towards a single value which provides another mechanism for brightening loops after they are first created.

Authors: McCarthy, M.I., Longcope, D.W., Malanushenko, A., McKenzie, D.E.

Publication Status: accepted for publication in ApJ
Last Modified: 2019-11-18 20:03
Go to main E-Print page  Edit Entry  Download Preprint  Delete Entry 

Go to main E-Print pageGo to main E-Print page.
Download PreprintDownload Preprint.
Submitter's HomepageSubmitters Homepage.
Edit EntryEdit Entry.
Delete AbstractDelete abstract.

Abstracts by Author
Measuring and modeling the rate of separator reconnection between an emerging and existing active region

Related Pages
MSU Solar Physics.
Max Millennium Science Mail Archive.
Max Millennium Message of the Day Mail Archive.
Max Millennium Flare Catalog

Archive Maintainer
Alisdair Davey

© 2000-2020 Solar Physics Group - Montana State University