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Related papers: The Evershed Effect with SOT/Hinode

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High resolution spectropolarimetric observations of 3 sunspots taken with Hinode demonstrate the existence of supersonic downflows at or close to the umbra-penumbra boundary which have not been reported before. These downflows are confined…

Solar and Stellar Astrophysics · Physics 2015-05-20 Rohan E. Louis , Luis R. Bellot Rubio , Shibu K. Mathew , P. Venkatakrishnan

The relation between the Evershed flow and moving magnetic features (MMFs) is studied using high-cadence, simultaneous spectropolarimetric measurements of a sunspot in visible (630.2 nm) and near-infrared (1565 nm) lines. Doppler…

Astrophysics · Physics 2011-02-11 D. Cabrera Solana , L. R. Bellot Rubio , C. Beck , J. C. del Toro Iniesta

The flows in and around sunspots are rich in detail. Starting with the Evershed flow along low-lying flow channels, which are cospatial with the horizontal penumbral magnetic fields, Evershed clouds may continue this motion at the periphery…

Solar and Stellar Astrophysics · Physics 2015-05-19 Carsten Denker , Meetu Verma

There have been a few reports in the literature of counter-Evershed flows observed in well developed sunspot penumbrae, i.e. flows directed towards the umbra along penumbral filaments. Here we investigate the driving forces of such…

Solar and Stellar Astrophysics · Physics 2018-01-24 A. L. Siu-Tapia , M. Rempel , A. Lagg , S. K. Solanki

I deduced a 3-D sunspot model that is in agreement with spectropolarimetric observations, to address the question of penumbral heating by the repetitive rise of flow channels. I performed inversions of data taken simultaneously in infrared…

Astrophysics · Physics 2009-11-13 C. Beck

High resolution spectropolarimetric observations by Hinode reveal the existence of supersonic downflows at the umbra-penumbra boundary of 3 sunspots that was recently reported by Louis et al. (2010). These downflows are observed to be…

Solar and Stellar Astrophysics · Physics 2015-03-17 Rohan E. Louis , Luis R. Bellot Rubio , Shibu K. Mathew , P. Venkatakrishnan

We study supersonic Evershed downflows in a sunspot penumbra by means of high spatial resolution spectropolarimetric data acquired in the Fe I 617.3 nm line with the CRISP instrument at the Swedish 1-m Solar Telescope. Physical observables,…

Solar and Stellar Astrophysics · Physics 2016-12-14 Sara Esteban Pozuelo , Luis R. Bellot Rubio , Jaime de la Cruz Rodriguez

The inverse Evershed flow (IEF) is an inflow of material into the penumbra of sunspots in the solar chromosphere that occurs along dark, elongated superpenumbral fibrils extending from about the outer edge of the moat cell to the sunspot.…

Solar and Stellar Astrophysics · Physics 2020-03-18 C. Beck , D. P. Choudhary

Sunspot fine structure has been modeled in the past by a combination of idealized magneto-convection simulations and simplified models that prescribe the magnetic field and flow structure to a large degree. Advancement in numerical methods…

Solar and Stellar Astrophysics · Physics 2015-05-20 Matthias Rempel

We describe a scenario for the topology of the magnetic field in penumbrae that accounts for recent observations showing upflows, downflows, and reverse magnetic polarities. According to our conjecture, short narrow magnetic loops fill the…

Solar and Stellar Astrophysics · Physics 2015-05-13 J. Sanchez Almeida

Using Hinode SP and G-band observations, we examined the relationship between magnetic field structure and penumbral size as well as Evershed flow speed. The latter two are positively correlated with magnetic inclination angle or horizontal…

Solar and Stellar Astrophysics · Physics 2015-05-27 Na Deng , Toshifumi Shimizu , Debi Prasad Choudhary , Haimin Wang

We present G-band and Ca II H observations of NOAA AR 10930 obtained by Hinode/SOT on 2006 December 6 covering an X6.5 flare. Local Correlation Tracking (LCT) technique was applied to the foreshortening-corrected G-band image series to…

Solar and Stellar Astrophysics · Physics 2015-05-27 Na Deng , Chang Liu , Debi Prasad Choudhary , Haimin Wang

Continuous observations of sunspot penumbrae with the Solar Optical Telescope aboard \textit{Hinode} clearly show that the outer boundary of the penumbra fluctuates around its averaged position. The penumbral outer boundary moves inward…

We studied the variations of line-of-sight photospheric plasma flows during the formation phase of the penumbra around a pore in Active Region NOAA 11490. We used a high spatial, spectral, and temporal resolution data set acquired by the…

Solar and Stellar Astrophysics · Physics 2016-07-06 M. Murabito , P. Romano , S. L. Guglielmino , F. Zuccarello , S. K. Solanki

Context: Observations at 0.1" have revealed the existence of dark cores in the bright filaments of sunspot penumbrae. Expectations are high that such dark-cored filaments are the basic building blocks of the penumbra, but their nature…

Astrophysics · Physics 2008-10-07 B. Ruiz Cobo , L. R. Bellot Rubio

The sunspot penumbra comprises numerous thin, radially elongated filaments that are central for heat transport within the penumbra, but whose structure is still not clear. To investigate the fine-scale structure of these filaments, we…

Solar and Stellar Astrophysics · Physics 2015-06-16 Sanjiv Kumar Tiwari , Michiel van Noort , Andreas Lagg , Sami K. Solanki

Whereas penumbral models during the last 15 years have been successful in explaining Evershed flows and magnetic field inclination variations in terms of flux tubes, the lack of contact between these models and a convective process needed…

Astrophysics · Physics 2009-11-13 G. B. Scharmer

[Abridged] The magnetic and kinematic properties of the photospheric Evershed flow are relatively well known, but we are still far from a complete understanding of its nature. The evolution of the flow with time, which is mainly due to…

Astrophysics · Physics 2009-11-13 D. Cabrera Solana , L. R. Bellot Rubio , C. Beck , J. C. del Toro Iniesta

We observed a C-class flare at the outer boundary of the super-penumbra of a sunspot. The flare was triggered by an emerging magnetic bipolar region that was obliquely oriented with respect to the super-penumbral fibrils. The flare started…

Solar and Stellar Astrophysics · Physics 2018-10-17 S. Liu , H. Q. Zhang , D. P. Choudhary , A. K. Srivastava , B. N. Dwivedi

In the past two decades, the complex nature of sunspots has been disclosed with high-resolution observations. One of the most important findings is the "uncombed" penumbral structure, where a more horizontal magnetic component carrying most…

Solar and Stellar Astrophysics · Physics 2012-03-13 Haimin Wang , Na Deng , Chang Liu