Zirin, Harold and Liggett, Margaret A. (1987) Delta spots and great flares. Solar Physics, 113 (1-2). pp. 267-283. ISSN 0038-0938. doi:10.1007/bf00147707. https://resolver.caltech.edu/CaltechAUTHORS:20200602-123444467
![[img]](https://authors.library.caltech.edu/style/images/fileicons/application_pdf.png) |
PDF (ADS)
- Published Version
See Usage Policy. 2MB |
Use this Persistent URL to link to this item: https://resolver.caltech.edu/CaltechAUTHORS:20200602-123444467
Abstract
Using eighteen years of observations at Big Bear, we summarize the development of δ spots and the great flares they produce. We find δ groups to develop in three ways: eruption of a single complex active region formed below the surface, eruption of large satellite spots near (particularly in front of) a large older spot, or collision of spots of opposite polarity from different dipoles. Our sample of twenty-one δ spots shows that once they lock together, they never separate, although rarely an umbra is ejected. The δ spots are already disposed to their final form when they emerge. The driving force for the shear is spot motion, either flux emergence or the forward motion of p spots in an inverted magnetic configuration.
| Item Type: | Article | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|
| Related URLs: |
| |||||||||
| Additional Information: | © 1987 by D. Reidel Publishing Company. Published 01 January 1987. This work was supported by NASA under NGL 05-002-034, the NSF under ATM-8513577, and the AFOSR through AFOSR-87-0034. We are grateful to the Big Bear staff for gathering the data, and to Prof. K. Tanaka for many useful discussions. | |||||||||
| Funders: |
| |||||||||
| Subject Keywords: | Flare; Fibril; Active Region; Opposite Polarity; Forward Motion | |||||||||
| Issue or Number: | 1-2 | |||||||||
| DOI: | 10.1007/bf00147707 | |||||||||
| Record Number: | CaltechAUTHORS:20200602-123444467 | |||||||||
| Persistent URL: | https://resolver.caltech.edu/CaltechAUTHORS:20200602-123444467 | |||||||||
| Official Citation: | Zirin, H., Liggett, M.A. Delta spots and great flares. Sol Phys 113, 267–283 (1987). https://doi.org/10.1007/BF00147707 | |||||||||
| Usage Policy: | No commercial reproduction, distribution, display or performance rights in this work are provided. | |||||||||
| ID Code: | 103637 | |||||||||
| Collection: | CaltechAUTHORS | |||||||||
| Deposited By: | Tony Diaz | |||||||||
| Deposited On: | 02 Jun 2020 20:15 | |||||||||
| Last Modified: | 16 Nov 2021 18:23 |
Repository Staff Only: item control page
