NDLI: Magnetic Helicity Budget of Solar-Active Regions from the Photosphere to Magnetic Clouds

Content Provider	Springer Nature Link
Author	Mandrini, C.H. Démoulin, P. Van Driel Gesztelyi, L. Van Driel Gesztelyi, L. Van Driel Gesztelyi, L. Van Driel Gesztelyi, L. L.M. Fuentes, M.C. López
Copyright Year	2004
Abstract	We have analyzed the long-term evolution of two active regions (ARs) from their emergence through their decay using observations from several instruments on board SoHO (MDI, EIT and LASCO) and Yohkoh/SXT. We have computed the evolution of the relative coronal magnetic helicity combining data from MDI and SXT with a linear force-free model of the coronal magnetic field. Next, we have computed the injection of helicity by surface differential rotation using MDI magnetic maps. To estimate the depletion of helicity we have counted all the CMEs of which these ARs have been the source, and we have evaluated their magnetic helicity assuming a one to one correspondence with magnetic clouds with an average helicity contain. When these three values (variation of coronal magnetic helicity, injection by differential rotation and ejection via CMEs) are compared, we find that surface differential rotation is a minor contributor to the helicity budget since CMEs carry away at least 10 times more helicity than the one differential rotation can provide. Therefore, the magnetic helicity flux needed in the global balance should come from localized photospheric motions that, at least partially, reflect the emergence of twisted flux tubes. We estimate that the total helicity carried away in CMEs can be provided by the end-to-end helicity of the flux tubes forming these ARs. Therefore, we conclude that most of the helicity ejected in CMEs is generated below the photosphere and emerges with the magnetic flux.
Starting Page	319
Ending Page	344
Page Count	26
File Format	PDF
ISSN	0004640X
Journal	Astrophysics and Space Science
Volume Number	290
Issue Number	3-4
e-ISSN	1572946X
Language	English
Publisher	Kluwer Academic Publishers
Publisher Date	2004-01-01
Publisher Place	Dordrecht
Access Restriction	One Nation One Subscription (ONOS)
Subject Keyword	Astronomy
Content Type	Text
Resource Type	Article
Subject	Astronomy and Astrophysics Space and Planetary Science

Sl.	Authority	Responsibilities	Communication Details
1	Ministry of Education (GoI), Department of Higher Education	Sanctioning Authority	https://www.education.gov.in/ict-initiatives
2	Indian Institute of Technology Kharagpur	Host Institute of the Project: The host institute of the project is responsible for providing infrastructure support and hosting the project	https://www.iitkgp.ac.in
3	National Digital Library of India Office, Indian Institute of Technology Kharagpur	The administrative and infrastructural headquarters of the project	Dr. B. Sutradhar bsutra@ndl.gov.in
4	Project PI / Joint PI	Principal Investigator and Joint Principal Investigators of the project	Dr. B. Sutradhar bsutra@ndl.gov.in Prof. Saswat Chakrabarti will be added soon
5	Website/Portal (Helpdesk)	Queries regarding NDLI and its services	support@ndl.gov.in
6	Contents and Copyright Issues	Queries related to content curation and copyright issues	content@ndl.gov.in
7	National Digital Library of India Club (NDLI Club)	Queries related to NDLI Club formation, support, user awareness program, seminar/symposium, collaboration, social media, promotion, and outreach	clubsupport@ndl.gov.in
8	Digital Preservation Centre (DPC)	Assistance with digitizing and archiving copyright-free printed books	dpc@ndl.gov.in
9	IDR Setup or Support	Queries related to establishment and support of Institutional Digital Repository (IDR) and IDR workshops	idr@ndl.gov.in

Determination of magnetic helicity content of solar active regions from SOHO/MDI magnetograms

Horizontal Flows in the Photosphere and Subphotosphere of Two Active Regions

Validation and Benchmarking of a Practical Free Magnetic Energy and Relative Magnetic Helicity Budget Calculation in Solar Magnetic Structures

The Properties of the Tilts of Bipolar Solar Regions

Helicity of solar active regions from a dynamo model

Comparing Values of the Relative Magnetic Helicity in Finite Volumes

Infrared photometry of solar active regions

A Note on Computation of Relative Magnetic-Helicity Flux Across the Photosphere

Sign-Singularity of the Current Helicity in Solar Active Regions

Magnetic Helicity Budget of Solar-Active Regions from the Photosphere to Magnetic Clouds

Similar Documents

Determination of magnetic helicity content of solar active regions from SOHO/MDI magnetograms

Horizontal Flows in the Photosphere and Subphotosphere of Two Active Regions

Validation and Benchmarking of a Practical Free Magnetic Energy and Relative Magnetic Helicity Budget Calculation in Solar Magnetic Structures

The Properties of the Tilts of Bipolar Solar Regions

Helicity of solar active regions from a dynamo model

Comparing Values of the Relative Magnetic Helicity in Finite Volumes

Infrared photometry of solar active regions

A Note on Computation of Relative Magnetic-Helicity Flux Across the Photosphere

Sign-Singularity of the Current Helicity in Solar Active Regions

Magnetic Helicity Budget of Solar-Active Regions from the Photosphere to Magnetic Clouds