Zobrazeno 1 - 10
of 128
pro vyhledávání: '"Jurcak, J."'
The magnetic properties of the umbra-penumbra (UP) boundary of sunspots and the boundary of pores at various evolutionary stages have been characterised using datasets from different instruments. We aim to study the differences between the intensity
Externí odkaz:
http://arxiv.org/abs/2406.15272
Autor:
García-Rivas, M., Jurčák, J., González, N. Bello, Borrero, J. M., Schlichenmaier, R., Lindner, P.
Publikováno v:
A&A 686, A112 (2024)
Context. Fully fledged penumbrae have been widely studied both observationally and theoretically. Yet the relatively fast process of penumbra formation has not been studied closely with high spatial resolution. Aims. We investigate the stages previou
Externí odkaz:
http://arxiv.org/abs/2403.18455
Publikováno v:
2021A&A...656A..92S
We analyse a sunspot simulation in an effort to understand the origin of the convective instabilities giving rise to the penumbral and umbral distinct regimes. We applied the criterion from Gough \& Tayler (1966), accounting for the stabilising effec
Externí odkaz:
http://arxiv.org/abs/2210.17245
Autor:
Noda, C. Quintero, Schlichenmaier, R., Rubio, L. R. Bellot, Löfdahl, M. G., Khomenko, E., Jurcak, J., Leenaarts, J., Kuckein, C., Manrique, S. J. González, Gunar, S., Nelson, C. J., Rodríguez, J. de la Cruz, Tziotziou, K., Tsiropoula, G., Aulanier, G., Collados, M., team, the EST
Publikováno v:
A&A 666, A21 (2022)
The European Solar Telescope (EST) is a project aimed at studying the magnetic connectivity of the solar atmosphere, from the deep photosphere to the upper chromosphere. Its design combines the knowledge and expertise gathered by the European solar p
Externí odkaz:
http://arxiv.org/abs/2207.10905
Publikováno v:
A&A 649, A129 (2021)
Context. Analyses of magnetic properties on umbrae boundaries led to the Jurcak criterion, which states that umbra-penumbra boundaries in stable sunspots are equally defined by a constant value of the vertical magnetic field, Bver_crit, and by 0.5 co
Externí odkaz:
http://arxiv.org/abs/2102.08459
Autor:
Schlichenmaier, R., Rubio, L. R. Bellot, Collados, M., Erdelyi, R., Feller, A., Fletcher, L., Jurcak, J., Khomenko, E., Leenaarts, J., Matthews, S., Belluzzi, L., Carlsson, M., Dalmasse, K., Danilovic, S., Gömöry, P., Kuckein, C., Sainz, R. Manso, Gonzalez, M. Martinez, Mathioudakis, M., Ortiz, A., Riethmüller, T. L., van der Voort, L. Rouppe, Simoes, P. J. A., Bueno, J. Trujillo, Utz, D., Zuccarello, F.
The European Solar Telescope (EST) is a research infrastructure for solar physics. It is planned to be an on-axis solar telescope with an aperture of 4 m and equipped with an innovative suite of spectro-polarimetric and imaging post-focus instrumenta
Externí odkaz:
http://arxiv.org/abs/1912.08650
Publikováno v:
A&A 620, A191 (2018)
It was empirically determined that the umbra-penumbra boundaries of stable sunspots are characterized by a constant value of the vertical magnetic field. We analyzed the evolution of the photospheric magnetic field properties of a decaying sunspot be
Externí odkaz:
http://arxiv.org/abs/1810.13185
Publikováno v:
A&A 607, A36 (2017)
Context. The Evershed effect, a nearly horizontal outflow of material seen in the penumbrae of sunspots in the photospheric layers, is a common characteristic of well-developed penumbrae, but is still not well understood. Even less is known about pho
Externí odkaz:
http://arxiv.org/abs/1709.07386
Acoustic and magnetoacoustic waves are among the possible candidate mechanisms that heat the upper layers of solar atmosphere. A weak chromospheric plage near a large solar pore NOAA 11005 was observed on October 15, 2008 in the lines Fe I 617.3 nm a
Externí odkaz:
http://arxiv.org/abs/1605.04794
Autor:
Sobotka, M., Dudík, J., Denker, C., Balthasar, H., Jurčák, J., Liu, W., Berkefeld, T., Vera, M. Collados, Feller, A., Hofmann, A., Kneer, F., Kuckein, C., Lagg, A., Louis, R. E., von der Lühe, O., Nicklas, H., Schlichenmaier, R., Schmidt, D., Schmidt, W., Sigwarth, M., Solanki, S. K., Soltau, D., Staude, J., Strassmeier, K. G., Volkmer, R., Waldmann, T.
Publikováno v:
A&A 596, A1 (2016)
A small flare ribbon above a sunspot umbra in active region 12205 was observed on November 7, 2014, at 12:00 UT in the blue imaging channel of the 1.5 m GREGOR telescope, using a 1 A Ca II H interference filter. Context observations from the Atmosphe
Externí odkaz:
http://arxiv.org/abs/1605.00464