Detection of Emerging Sunspot Regions in the Solar Interior

@article{Ilonidis2011DetectionOE,
  title={Detection of Emerging Sunspot Regions in the Solar Interior},
  author={Stathis Ilonidis and Junwei Zhao and Alexander G. Kosovichev},
  journal={Science},
  year={2011},
  volume={333},
  pages={993 - 996}
}
Helioseismic observations allow the detection of sunspots before they emerge at the surface of the Sun. Sunspots are regions where strong magnetic fields emerge from the solar interior and where major eruptive events occur. These energetic events can cause power outages, interrupt telecommunication and navigation services, and pose hazards to astronauts. We detected subsurface signatures of emerging sunspot regions before they appeared on the solar disc. Strong acoustic travel-time anomalies of… 

A new look at sunspot formation using theory and observations

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Helioseismology is capable of detecting signatures of emerging sunspot regions in the solar interior before they appear at the surface. Here we present measurements that show the rising motion of the

DETECTION OF THE HORIZONTAL DIVERGENT FLOW PRIOR TO THE SOLAR FLUX EMERGENCE

It is widely accepted that solar active regions including sunspots are formed by the emerging magnetic flux from the deep convection zone. In previous numerical simulations, we found that the

PROBING THE SHALLOW CONVECTION ZONE: RISING MOTION OF SUBSURFACE MAGNETIC FIELDS IN THE SOLAR ACTIVE REGION

In this Letter, we present a seismological detection of a rising motion of magnetic flux in the shallow convection zone of the Sun, and show estimates of the emerging speed and its decelerating

New Insights into Sunspots Through Hinode Observations

Studies on sunspots have a very long history mostly supported by ground-based observations. However, the detailed evolution of sunspot magnetic field structures are revealed by Hinode observations of

Comment on “Detection of Emerging Sunspot Regions in the Solar Interior”

TLDR
An independent analysis using helioseismic holography does not confirm travel-time anomalies associated with emerging sunspot regions before their appearance on the solar surface, consistent with expectations based on current emerging flux models.

Sub-photosphere to Solar Atmosphere Connection

Magnetic fields extend from the solar interior through the atmosphere. The formation and evolution of active regions can be studied by measuring subsurface flows with local helioseismology. The

Photospheric Velocity Structures during the Emergence of Small Active Regions on the Sun

We study the plasma flows in the solar photosphere during the emergence of two small active regions, NOAA 9021 and 10768. Using Solar and Heliospheric Observatory/Michelson Doppler Imager data, we

Statistical Analysis of the Horizontal Divergent Flow in Emerging Solar Active Regions

Solar active regions (ARs) are thought to be formed by magnetic fields from the convection zone. Our flux emergence simulations revealed that a strong horizontal divergent flow (HDF) of unmagnetized

A low upper limit on the subsurface rise speed of solar active regions

TLDR
It is shown that measurements of horizontal flows at the solar surface around emerging active regions, in combination with numerical simulations of solar magnetoconvection, can constrain the subsurface rise speed of emerging magnetic flux.
...

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