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Related papers: Subsurface Meridional Circulation in the Active Be…

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We explore the general properties of near-surface flows around solar active regions. Helioseismic holography is applied to HMI Dopplergrams yielding nearly 5000 flow measurements of 336 unique active regions observed by the Solar Dynamics…

Solar and Stellar Astrophysics · Physics 2019-03-20 D. C. Braun

Observations of the meridional circulation of the Sun, which plays a key role in the operation of the solar dynamo, indicate that its speed varies with the solar cycle, becoming faster during the solar minima and slower during the solar…

Solar and Stellar Astrophysics · Physics 2017-10-11 Gopal Hazra , Arnab Rai Choudhuri

Meridional flow is thought to play a very important role in the dynamics of the solar convection zone; however, because of its relatively small amplitude, precisely measuring it poses a significant challenge. Here we present a complete…

Solar and Stellar Astrophysics · Physics 2015-06-02 J. Jackiewicz , A. Serebryanskiy , S. Kholikov

The form of the solar meridional circulation is a very important ingredient for mean field flux transport dynamo models. Yet a shroud of mystery still surrounds this large-scale flow, given that its measurement using current helioseismic…

Solar and Stellar Astrophysics · Physics 2015-02-17 Dario Passos , Paul Charbonneau , Mark Miesch

The solar meridional flow is an important ingredient in Babcock-Leighton type models of the solar dynamo. Global variations of this flow have been suggested to explain the variations in the amplitudes and lengths of the activity cycles.…

Solar and Stellar Astrophysics · Physics 2015-05-19 R. H. Cameron , M. Schüssler

The meridional circulation of the Sun, which is observed to be poleward at the surface, should have a return flow at some depth. Since large-scale flows like the differential rotation and the meridional circulation are driven by turbulent…

Solar and Stellar Astrophysics · Physics 2020-08-24 Arnab Rai Choudhuri

As the global magnetic field of the Sun has an activity cycle, one expects to observe some variation of the dynamical properties of the flows visible in the photosphere. We investigate the flow field during the solar cycle by analysing…

Solar and Stellar Astrophysics · Physics 2017-02-15 Th. Roudier , J. M. Malherbe , G. M. Mirouh

We present analysis of the evolution of subsurface flows in and around active regions with peculiar magnetic configurations and compare their characteristics with the normal active regions. We also study the zonal and meridional components…

Solar and Stellar Astrophysics · Physics 2024-12-25 Kiran Jain , Sushanta C. Tripathy

The results of determinations of the azimuthal and meridional velocities by time-distance helioseismology from Helioseismic and Magnetic Imager (HMI) onboard Solar Dynamics Observatory (SDO) from May 2010 to September 2020 at latitudes from…

Solar and Stellar Astrophysics · Physics 2021-02-26 Alexander V. Getling , Alexander G. Kosovichev , Junwei Zhao

We investigate spatio-temporal evolution of high-degree acoustic mode frequencies of the Sun and the surface magnetic activity, over the course of multiple solar cycles, to improve our understanding of the connection between the solar…

Solar and Stellar Astrophysics · Physics 2023-12-20 Mackenzie A. Baird , Sushanta C. Tripathy , Kiran Jain

Using data from the Michelson Doppler Imager (MDI) instrument on board the Solar and Heliospheric Observatory (SOHO), we study the large-scale velocity fields in the outer part of the solar convection zone using the ring diagram technique.…

Astrophysics · Physics 2015-06-24 Sarbani Basu , H. M. Antia

Doppler shifts of the Fe I spectral line at lambda5250 Angstroms from the full solar disk obtained over the period 1986 to 2009 are analyzed to determine the circulation velocity of the solar surface along meridional planes. Simultaneous…

Solar and Stellar Astrophysics · Physics 2015-05-20 Roger K. Ulrich

Using time-distance helioseismology applied to 14-years of SDO/HMI observations spanning solar cycle 24 and rising phase of cycle 25, we present evidence that meridional flows in the lower half of the near-surface shear layer (NSSL),…

Solar and Stellar Astrophysics · Physics 2026-04-21 Anisha Sen , S. P. Rajaguru , Ruizhu Chen , Junwei Zhao , Shukur Kholikov

We studied the solar surface flows (differential rotation and meridional circulation) using a magnetic element feature tracking technique by which the surface velocity is obtained using magnetic field data. We used the line-of-sight…

Solar and Stellar Astrophysics · Physics 2018-09-05 Shinsuke Imada , Masashi Fujiyama

Convection, differential rotation, and meridional circulation of solar plasma are studied based on helioseismic data covering the period from May 2010 to August 2024, significantly prolonged compared to that previously considered. Depth…

Solar and Stellar Astrophysics · Physics 2025-04-22 A. V. Getling , A. G. Kosovichev

The faster meridional flow that preceded the solar cycle 23/24 minimum is thought to have led to weaker polar field strengths, producing the extended solar minimum and the unusually weak cycle 24. To determine the impact of meridional flow…

Solar and Stellar Astrophysics · Physics 2015-06-22 Lisa Upton , David H. Hathaway

Solar sub-surface fluid topology provides an indirect approach to examine the internal characteristics of active regions (ARs). Earlier studies have revealed the prevalence of strong flows in the interior of ARs having complex magnetic…

Solar and Stellar Astrophysics · Physics 2010-04-19 R. A. Maurya , A. Ambastha

We present and discuss results from time-distance helioseismic measurements of meridional circulation in the solar convection zone using 4 years of Doppler velocity observations by the Helioseismic and Magnetic Imager (HMI) onboard the…

Solar and Stellar Astrophysics · Physics 2015-11-11 S. P. Rajaguru , H. M. Antia

Large-scale plasma flows in the Sun's convection zone likely play a major role in solar dynamics on decadal timescales. In particular, quantifying meridional motions is a critical ingredient for understanding the solar cycle and the…

Solar and Stellar Astrophysics · Physics 2015-06-19 Shukur Kholikov , Alexander Serebryanskiy , Jason Jackiewicz

Meridional flow is crucial in generating the solar poloidal magnetic field by facilitating the poleward transport of the field from the decayed Bipolar Magnetic Regions (BMRs). As the meridional circulation changes with the stellar rotation…

Solar and Stellar Astrophysics · Physics 2024-07-24 Vindya Vashishth , Bidya Binay Karak