Identification

Title

Magnetic field evolution of the solar active region 13664

Abstract

On 2024 May 10–11, the strongest geomagnetic storm since 2003 November occurred, with a peak Dst index of −412 nT. The storm was caused by NOAA active region (AR) 13664, which was the source of a large number of coronal mass ejections and flares, including 12 X-class flares. Starting from about May 7, AR 13664 showed a steep increase in its size and (free) magnetic energy, along with increased flare activity. In this study, we perform 3D magnetic field extrapolations with the NF2 nonlinear force-free code based on physics-informed neural networks (R. Jarolim et al.). In addition, we introduce the computation of the vector potential to achieve divergence-free solutions. We extrapolate vector magnetograms from the Solar Dynamics Observatory’s Helioseismic and Magnetic Imager at the full 12 minute cadence from 2024 May 5 00:00 to 11 04:36 UT, in order to understand the AR’s magnetic evolution and the large eruptions it produced. A decrease in the calculated relative free magnetic energy can be related to solar flares in ∼90% of the cases, and all considered X-class flares are reflected by a decrease in the relative free magnetic energy. Regions of enhanced free magnetic energy and depleted magnetic energy between the start and end times of major X-class flares show spatial alignment with brightness increases in extreme-ultraviolet observations. We provide a detailed analysis of the X3.9-class flare on May 10, where we show that the interaction between separated magnetic domains is directly linked to major flaring events. With this study, we provide a comprehensive data set of the magnetic evolution of AR 13664 and make it publicly available for further analysis.

Resource type

document

Resource locator

Unique resource identifier

code

https://n2t.net/ark:/85065/d7251phv

codeSpace

Dataset language

eng

Spatial reference system

code identifying the spatial reference system

Classification of spatial data and services

Topic category

geoscientificInformation

Keywords

Keyword set

keyword value

Text

originating controlled vocabulary

title

Resource Type

reference date

date type

publication

effective date

2016-01-01T00:00:00Z

Geographic location

West bounding longitude

East bounding longitude

North bounding latitude

South bounding latitude

Temporal reference

Temporal extent

Begin position

End position

Dataset reference date

date type

publication

effective date

2024-11-01T00:00:00Z

Frequency of update

Quality and validity

Lineage

Conformity

Data format

name of format

version of format

Constraints related to access and use

Constraint set

Use constraints

<span style="font-family:Arial;font-size:10pt;font-style:normal;" data-sheets-root="1">Copyright author(s). This work is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License.</span>

Limitations on public access

None

Responsible organisations

Responsible party

contact position

OpenSky Support

organisation name

UCAR/NCAR - Library

full postal address

PO Box 3000

Boulder

80307-3000

email address

opensky@ucar.edu

web address

http://opensky.ucar.edu/

name: homepage

responsible party role

pointOfContact

Metadata on metadata

Metadata point of contact

contact position

OpenSky Support

organisation name

UCAR/NCAR - Library

full postal address

PO Box 3000

Boulder

80307-3000

email address

opensky@ucar.edu

web address

http://opensky.ucar.edu/

name: homepage

responsible party role

pointOfContact

Metadata date

2025-07-10T19:57:40.605088

Metadata language

eng; USA