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Related papers: A Topology for the Penumbral Magnetic Fields

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Inversions of spectropolarimetric observations of penumbral filaments deliver the stratification of different physical quantities in an optical depth scale. However, without establishing a geometrical height scale their three-dimensional…

Solar and Stellar Astrophysics · Physics 2013-03-14 K. G. Puschmann , B. Ruiz Cobo , V. Martínez Pillet

Using spectropolarimetric data of an Active Region (AR) filament we have carried out inversions in order to infer vector magnetic fields in the photosphere (Si I line) and in the chromosphere (He I line). Our filament lies above the…

Solar and Stellar Astrophysics · Physics 2010-10-21 Christoph Kuckein , Rebecca Centeno , Valentin Martinez Pillet

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

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 recently presented evidence that stable umbra-penumbra boundaries are characterised by a distinct canonical value of the vertical component of the magnetic field, $B^{\rm stable}_{\rm ver}$. In order to trigger the formation of a…

Solar and Stellar Astrophysics · Physics 2016-12-28 Jan Jurcak , Nazaret Bello Gonzalez , Rolf Schlichenmaier , Reza Rezaei

While it is being conjectured that a chromospheric canopy plays a role in penumbra formation, it has been difficult to find observational evidence of the connectivity between the photosphere and the chromosphere. We investigate the…

Solar and Stellar Astrophysics · Physics 2023-05-10 P. Lindner , C. Kuckein , S. J. González Manrique , N. Bello González , L. Kleint , T. Berkefeld

We present a combined model for magnetic field generation and transport in cool stars with outer convection zones. The mean toroidal magnetic field, which is generated by a cyclic thin-layer alpha-omega dynamo at the bottom of the…

Solar and Stellar Astrophysics · Physics 2011-11-11 Emre Işık , Dieter Schmitt , Manfred Schüssler

Topological textures in magnetically ordered materials are important case studies for fundamental research with promising applications in data science. They can also serve as photonic elements to mold electromagnetic fields endowing them…

The evolution of photospheric flow and magnetic fields before and after flares can provide important information regarding the flare triggering and back reaction processes. However, such studies on the flow field are rare due to the paucity…

Solar and Stellar Astrophysics · Physics 2018-02-14 Jiasheng Wang , Chang Liu , Na deng , Haimin Wang

Solar prominences are an important tool for studying the structure and evolution of the coronal magnetic field. Here we consider so-called "hedgerow" prominences, which consist of thin vertical threads. We explore the possibility that such…

Solar and Stellar Astrophysics · Physics 2015-05-18 A. A. van Ballegooijen , S. R. Cranmer

Maps of polarized dust emission of molecular clouds reveal the morphology of the magnetic field associated with star-forming regions. In particular, polarization maps of hub-filament systems show the distortion of magnetic field lines…

Astrophysics of Galaxies · Physics 2024-05-21 Domitilla Tapinassi , Daniele Galli , Marco Padovani , Henrik Beuther

We use spectro-polarimetric data recorded by Hinode to analyze the magnetic field configuration of a part of a sunspot (AR 10923) where a bundle of penumbral filaments are intruding into its umbra. We want to explore the role of the sunspot…

Solar and Stellar Astrophysics · Physics 2024-05-15 Hashem Hamedivafa

The axisymmetric component of the large-scale solar magnetic fields has a pronounced poleward branch at higher latitudes. In order to clarify the origin of this branch we construct an axisymmetric model of the passive transport of the mean…

Astrophysics · Physics 2015-06-24 K. Petrovay , G. Szakaly

Magnetic fields emerging from the Sun's interior carry information about physical processes of magnetic field generation and transport in the convection zone. Soon after appearance on the solar surface the magnetic flux gets concentrated in…

Solar and Stellar Astrophysics · Physics 2009-11-13 A. G. Kosovichev

Moving magnetic features (MMFs) are small-size magnetic elements that are seen to stream out from sunspots, generally during their decay phase. Several observational results presented in the literature suggest them to be closely related to…

Solar and Stellar Astrophysics · Physics 2015-06-11 S. Criscuoli , D. Del Moro , F. Giannattasio , B. Viticchié , F. Giorgi , I. Ermolli , F. Zuccarello , F. Berrilli

High-resolution observations with the Swedish 1-m Solar Telescope (SST) and the Solar Dynamics Observatory (SDO) reveal rotating magnetic field structures that extend from the solar surface into the chromosphere and the corona. These…

Solar and Stellar Astrophysics · Physics 2015-06-22 Sven Wedemeyer , Oskar Steiner

We employ a 3-dimensional magnetohydrostatic model of a horizontal flux tube, embedded in a magnetic surrounding atmosphere, to successfully reproduce the azimuthal and center-to-limb variations of the Net Circular Polarization observed in…

Astrophysics · Physics 2009-11-13 J. M. Borrero , L. R. Bellot Rubio , D. A. N. Mueller

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

Using two simulations of 1.5D, for the first time, in Costa et al. (2009) and Shulz et al. (2010) we numerically reproduce the observational dark inflows described in Verwichte et al. (2005). We show that the dark tracks can be explained as…

Solar and Stellar Astrophysics · Physics 2015-05-27 L. S. Maglione , E. M. Schneiter , A. Costa , S. Elaskar

Plasma upflows with a Doppler shift exceeding -10 km/s at active region (AR) boundaries are considered potential sources of the nascent slow solar wind. We investigate the driving mechanisms of a pair of coronal upflow regions on the…