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Related papers: Spectral Diagnostics of Solar Photospheric Bright …

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Bright points (BPs) are ubiquitous, small-scale energetic events with multithermal signatures, typically observed in the chromosphere and linked to both photospheric structure and coronal composition. Their evolution is influenced by…

Solar and Stellar Astrophysics · Physics 2025-06-25 Llŷr Humphries , Huw Morgan , David Kuridze

Context. The solar corona maintains temperatures of a million Kelvin or more. The plasma heating mechanisms responsible for these extreme temperatures are still unclear. Large regions of magnetic activity in the photosphere cause extreme…

Solar and Stellar Astrophysics · Physics 2025-03-17 I. Kraus , Ph. -A. Bourdin , J. Zender , M. Bergmann , A. Hanslmeier

Context. The corona of the Sun is the part of the solar atmosphere with temperatures of over one million Kelvin, which needs to be heated internally in order to exist. This heating mechanism remains a mystery; we see large magnetically…

Solar and Stellar Astrophysics · Physics 2023-11-03 I. Kraus , Ph. -A. Bourdin , J. Zender , M. Bergmann , A. Hanslmeier

The sub-arcsec bright points (BP) associated with the small scale magnetic fields in the lower solar atmosphere are advected by the evolution of the photospheric granules. We measure various quantities related to the horizontal motions of…

Solar and Stellar Astrophysics · Physics 2012-05-28 LP. Chitta , A. A. van Ballegooijen , L. Rouppe van der Voort , E. E. DeLuca , R. Kariyappa

Plage regions are patches of concentrated magnetic field in the Sun's atmosphere where hot coronal loops are rooted. While previous studies have shed light on the properties of plage magnetic fields in the photosphere, there are still…

Solar and Stellar Astrophysics · Physics 2023-08-23 J. M. da Silva Santos , K. Reardon , G. Cauzzi , T. Schad , V. Martinez Pillet , A. Tritschler , F. Wöger , R. Hofmann , J. Stauffer , H. Uitenbroek

We present simultaneous spectropolarimetric observations of four visible and three infrared spectral lines from the VTT (Tenerife), together with speckle-reconstructed filtergrams in the G band and the CaII H line core from the DOT (La…

Astrophysics · Physics 2007-08-02 C. Beck , L. R. Bellot Rubio , R. Schlichenmaier , P. Suetterlin

Emerging flux regions (EFRs) are known to exhibit various sporadic local heating events in the lower atmosphere. To investigate the characteristics of these events, especially to link the photospheric magnetic fields and atmospheric…

Solar and Stellar Astrophysics · Physics 2017-02-15 Shin Toriumi , Yukio Katsukawa , Mark C. M. Cheung

The solar chromosphere is heated to temperatures higher than predicted by radiative equilibrium. This excess heating is greater in active regions where the magnetic field is stronger. We aim to investigate the magnetic topology associated…

Solar and Stellar Astrophysics · Physics 2022-05-04 J. M. da Silva Santos , S. Danilovic , J. Leenaarts , J. de la Cruz Rodríguez , X. Zhu , S. M. White , G. J. M. Vissers , M. Rempel

Context. The contribution of quiet-Sun regions to the solar irradiance variability is currently unclear. Some solar-cycle variations of the quiet-Sun physical structure, such as the temperature gradient, might affect the irradiance. The…

Solar and Stellar Astrophysics · Physics 2018-09-05 M. Faurobert , M. Carbillet , L. Marquis , A. Chiavassa , G. Ricort

A large fraction of gamma-ray burst (GRB) spectra are very hard below the peak. Indeed, the observed distribution of sub-peak power-law indices, $\alpha$, has been used as an argument for a photospheric origin of GRB spectra. Here, we…

High Energy Astrophysical Phenomena · Physics 2019-06-12 Zeynep Acuner , Felix Ryde , Hoi-Fung Yu

A magneto-hydrostatic model is constructed with spectropolarimetric properties close to those of solar photospheric magnetic bright points. Results of solar radiative magneto-convection simulations are used to produce the spatial structure…

Solar and Stellar Astrophysics · Physics 2015-05-18 S. Shelyag , M. Mathioudakis , F. P. Keenan , D. B. Jess

Coronal Bright Points (CBPs) are sets of small-scale coronal loops, connecting opposite magnetic polarities, primarily characterized by their enhanced extreme-ultraviolet (EUV) and X-ray emission. Being ubiquitous, they are thought to play…

Solar and Stellar Astrophysics · Physics 2023-03-01 Souvik Bose , Daniel Nóbrega-Siverio , Bart De Pontieu , Luc Rouppe van der Voort

Poynting flux generated by random shuffling of photospheric magnetic footpoints is transferred through the upper atmosphere of the Sun where the plasma is heated to over 1 MK in the corona. High spatiotemporal resolution observations of the…

Solar and Stellar Astrophysics · Physics 2024-11-20 L. P. Chitta , M. van Noort , H. N. Smitha , E. R. Priest , L. H. M. Rouppe van der Voort

Context. High-resolution observations of the solar photosphere reveal the presence of fine structures, in particular the so-called magnetic bright points (MBPs), which are small-scale features associated with strong magnetic field regions…

CONTEXT:The footpoints of quiet Sun Transition Region (TR) loops do not seem to coincide with the photospheric magnetic structures appearing in traditional low-sensitivity magnetograms. AIMS: To look for the so-far unidentified photospheric…

Astrophysics · Physics 2009-11-13 J. Sanchez Almeida , L. Teriaca , P. Suetterlin , D. Spadaro , U. Schuehle , R. J. Rutten

3He-rich solar energetic particles (SEPs) are believed to be accelerated in solar flares or jets by a mechanism that depends on the ion charge-to-mass (Q/M) ratio. It implies that the flare plasma characteristics (e.g., temperature) may be…

Solar and Stellar Astrophysics · Physics 2021-03-10 R. Bucik , S. M. Mulay , G. M. Mason , N. V. Nitta , M. I. Desai , M. A. Dayeh

Various bright structures abound in the chromosphere playing an essential role in the dynamics and evolution therein. Tentatively identifying the wave characteristics in the outer solar atmosphere helps to understand this layer better. One…

Solar and Stellar Astrophysics · Physics 2022-10-26 Rayhane Sadeghi , Ehsan Tavabi

We detected 2.8 bright points (BPs) per Mm$^2$ in the Quiet Sun (QS) with the New Solar Telescope (NST) at Big Bear Solar Observatory; using the TiO 705.68 nm spectral line, at an angular resolution ~ 0.1'' to obtain 30 min data sequence.…

Solar and Stellar Astrophysics · Physics 2015-05-27 Aleksandra Andic , J. Chae , K. Ahn , P. R. Goode , W. Cao , V. Yurchyshyn , V. Abramenko

Ellerman bombs (EBs) are tiny brightenings often observed near sunspots. The most impressive characteristic of the EB spectra is the two emission bumps in both wings of the H$\alpha$ and \ion{Ca}{II} 8542 {\AA} lines. High-resolution…

Solar and Stellar Astrophysics · Physics 2015-09-16 Z. Li , C. Fang , Y. Guo , P. F. Chen , Z. Xu , W. Cao

High resolution G-band images of the interior of a supergranulation cell show ubiquitous Bright Points (some 0.3 BPs per Mm^2). They are located in intergranular lanes and often form chains of elongated blobs whose smallest dimension is at…

Astrophysics · Physics 2009-11-10 J. Sanchez Almeida , I. Marquez , J. A. Bonet , I. Dominguez Cerdena , R. Muller