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Related papers: Supersonic Downflows in a Sunspot Light Bridge

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Solid evidence of magnetic reconnection is rarely reported within sunspots, the darkest regions with the strongest magnetic fields and lowest temperatures in the solar atmosphere. Using the world's largest solar telescope, the 1.6-meter…

The Solar Optical Telescope onboard Hinode revealed the fine-scale structure of the Evershed flow and its relation to the filamentary structures of the sunspot penumbra. The Evershed flow is confined in narrow channels with nearly…

Solar and Stellar Astrophysics · Physics 2015-05-13 Kiyoshi Ichimoto , SOT/Hinode-team

We have measured the meridional motions of the magnetic elements in the Sun's surface layers since 1996 and find systematic and substantial variations. In general the meridional flow speed is fast at cycle minima and slow at cycle maxima.…

Solar and Stellar Astrophysics · Physics 2015-06-19 David H. Hathaway , Lisa Upton

Context: Solar pores are small sunspots lacking a penumbra that have a prevailing vertical magnetic field component. They can include light bridges at places with locally reduced magnetic field. Like sunspots, they exhibit a wide range of…

Solar and Stellar Astrophysics · Physics 2015-06-17 M. Sobotka , M. Švanda , J. Jurčák , P. Heinzel , D. Del Moro , F. Berrilli

We discuss NICOLE inversions of Fe I 630.15 nm and 630.25 nm Stokes spectra from a sunspot penumbra recorded with the CRISP imaging spectropolarimeter on the Swedish 1-m Solar Telescope at a spatial resolution close to 0.15". We report on…

Solar and Stellar Astrophysics · Physics 2015-06-12 G. B. Scharmer , J. de la Cruz Rodríguez , P. Sütterlin , V. M. J. Henriques

We present unprecedented high-resolution TiO images and Fe I 1565 nm spectropolarimetric data of two light bridges taken by the 1.6-m Goode Solar Telescope at Big Bear Solar Observatory. In the first light bridge (LB1), we find striking…

Solar and Stellar Astrophysics · Physics 2018-10-10 Jingwen Zhang , Hui Tian , Sami K. Solanki , Haimin Wang , Hardi Peter , Kwangsu Ahn , Yan Xu , Yingjie Zhu , Wenda Cao , Jiansen He , Linghua Wang

Small-scale magnetic features are present everywhere in the solar photosphere. Theoretical models, numerical calculations, and simulations describing the formation of these features have existed for a few decades, but there are only a few…

Solar and Stellar Astrophysics · Physics 2015-05-27 G. Narayan

Sunspots are crucial for exploring how magnetic fields and plasma flows interact in the solar atmosphere, spanning from the stable photosphere to the shock-dominated chromosphere. To determine the thermal, magnetic, and kinematic properties…

Solar and Stellar Astrophysics · Physics 2026-04-29 A. Vicente Arevalo , J. M. Borrero , I. Milic , A. Pastor Yabar , I. Kontogiannis , A. G. M. Pietrow

Recent solar observations of bipolar light bridges (BLBs) in sunspots have, in a few individual cases, revealed magnetic fields up to 8.2 kG, which is at least twice as strong as typical values measured in sunspot umbrae. However, the small…

Solar and Stellar Astrophysics · Physics 2025-01-06 J. S. Castellanos Durán , A. Korpi-Lagg , S. K. Solanki , M. van Noort , N. Milanovic

We investigate the evolution of 5 granular-scale magnetic flux cancellations just outside the moat region of a sunspot by using accurate spectropolarimetric measurements and G-band images with the Solar Optical Telescope aboard Hinode. The…

Solar and Stellar Astrophysics · Physics 2015-05-18 M. Kubo , B. C. Low , B. W. Lites

Recent numerical simulations and observations of sunspots show a significant amount of opposite polarity magnetic field within the sunspot penumbra. Most of the opposite polarity field is associated with convective downflows. We present an…

Solar and Stellar Astrophysics · Physics 2019-11-06 Lokesh Bharti , Matthias Rempel

We present a series of numerical sunspot models addressing the subsurface field and flow structure in up to 16 Mm deep domains covering up to 2 days of temporal evolution. Changes in the photospheric appearance of the sunspots are driven by…

Solar and Stellar Astrophysics · Physics 2015-05-28 Matthias Rempel

A small decaying sunspot was observed with the Vacuum Tower Telescope (VTT) on Tenerife and the Japanese Hinode satellite. We obtained full Stokes scans in several wavelengths covering different heights in the solar atmosphere. Imaging time…

Solar and Stellar Astrophysics · Physics 2013-01-09 H. Balthasar , C. Beck , P. Gömöry , K. Muglach , K. G. Puschmann , T. Shimizu , M. Verma

The sunspot penumbra is usually observed in the photosphere and it is of particular interest for its magneto-convection which seems to transport the heat from the top of the convection zone into the solar atmosphere. It is well known that…

Solar and Stellar Astrophysics · Physics 2023-09-21 Paolo Romano , Francesco Schillirò , Mariachiara Falco

High-resolution broadband filtergrams of active region NOAA 11271 in Ca ii H and G band were obtained with the Solar Optical Telescope on board Hinode to identify the physical driver responsible for the dynamic and small-scale chromospheric…

Solar and Stellar Astrophysics · Physics 2015-06-19 Rohan E. Louis , Christian Beck , Kiyoshi Ichimoto

We investigate the flow field in the sunspot canopy using simultaneous Stokes vector spectropolarimetry of three sunspots ($\theta$ = 27, 50, 75 deg) and their surroundings in visible (630.15 and 630.25 nm) and near infrared (1564.8 and…

Astrophysics · Physics 2007-05-23 Reza Rezaei , R. Schlichenmaier , C. A. R. Beck , L. R. Bellot Rubio

Persistent outflows have recently been detected at boundaries of some active regions. Although these outflows are suggested to be possible sources of the slow solar wind, the nature of these outflows is poorly understood. Through an…

Solar and Stellar Astrophysics · Physics 2015-05-19 L. -J. Guo , H. Tian , J. -S. He

The moat flow, a radial outflow surrounding fully fledged sunspots, is a well characterised phenomenon. Nevertheless, its origin and especially its relation to the penumbra is still a controversial topic. We investigate the evolution of the…

Solar and Stellar Astrophysics · Physics 2018-11-06 Hanna Strecker , Nazaret Bello González

In this paper we propose an inversion strategy for the analysis of spectropolarimetric measurements taken by {\em Hinode} in the quiet Sun. The spectropolarimeter of the Solar Optical Telescope aboard {\em Hinode} records the Stokes spectra…

Solar granules are bright patterns surrounded by dark channels called intergranular lanes in the solar photosphere and are a manifestation of overshooting convection. Observational studies generally find stronger upflows in granules and…

Solar and Stellar Astrophysics · Physics 2017-11-01 T. Oba , T. L. Riethmüller , S. K. Solanki , Y. Iida , C. Quintero Noda , T. Shimizu