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Related papers: Spectral variations within solar flare ribbons

200 papers

In this paper, I will present the recent progress on circular-ribbon flares (CRFs) and their related activities, including coronal jets, filaments, CMEs, radio bursts, coronal dimmings, and coronal loop oscillations. Owing to the prevalence…

Solar and Stellar Astrophysics · Physics 2024-01-30 Qingmin Zhang

There is an ongoing debate about the origin and even the very existence of a high degree of linear polarization of some chromospheric spectral lines observed in solar flares. The standard explanation of these measurements is in terms of the…

Solar and Stellar Astrophysics · Physics 2015-06-17 Jiri Stepan , Petr Heinzel

The asymmetries observed in the line profiles of solar flares can provide important diagnostics of the properties and dynamics of the flaring atmosphere. In this paper the evolution of the Halpha and Ca II 8542 {\AA} lines are studied using…

Solar flare ribbons provide an important clue to the magnetic reconnection process and associated magnetic field topology in the solar corona. We detected a large-scale secondary flare ribbon of a circular shape that developed in…

Solar and Stellar Astrophysics · Physics 2017-12-13 Eun-Kyung Lim , Vasyl Yurchyshyn , Pankaj Kumar , Kyuhyoun Cho , Chaowei Jiang , Sujin Kim , Heesu Yang , Jongchul Chae , Kyung-Suk Cho , Jeongwoo Lee

Solar flares involve impulsive energy release, which results in enhanced radiation over a broad spectral range and a wide range of heights. In particular, line emission from the chromosphere can provide critical diagnostics of plasma…

Solar and Stellar Astrophysics · Physics 2015-06-23 Fatima Rubio da Costa , Lucia Kleint , Vahé Petrosian , Alberto Sainz Dalda , Wei Liu

We have explored the relationship between hard X-ray (HXR) emissions and Doppler velocities caused by the chromospheric evaporation in two X1.6 class solar flares on 2014 September 10 and October 22, respectively. Both events display double…

Solar and Stellar Astrophysics · Physics 2015-11-04 Dong Li , Zongjun Ning , Qingmin Zhang

A three-dimensional picture of the solar atmosphere's thermodynamics can be obtained by jointly analyzing multiple spectral lines that span many formation heights. In paper I, we found strong correlations between spectral shapes from a…

Solar and Stellar Astrophysics · Physics 2021-07-21 Brandon Panos , Lucia Kleint

Chromospheric flare ribbons observed in H-alpha appear well-organized when first examined: ribbons impulsively brighten, morphologically evolve, and exponentially decay back to pre-flare levels. Upon closer inspection of H-alpha flares,…

Solar and Stellar Astrophysics · Physics 2014-11-18 Michael S. Kirk , K. S. Balasubramaniam , Jason Jackiewicz , R. T. James McAteer

Solar pores are strongly magnetized regions lacking a photospheric penumbra and characterized by predominantly vertical magnetic fields. We present a multi-line study of flashes in a solar pore using high-resolution observations from the…

Solar and Stellar Astrophysics · Physics 2026-02-11 Sandeep Dubey , Christian Beck , Rahul Yadav , Tobias Felipe , Shibu K Mathew

We detect rapid downflows of 150-217 km/s in IRIS Si IV 1402.77 nm measurements of an X9-class solar flare on 2024 October 3rd. The fast redshift values persist for over 15 minutes from flare onset, and can be split into two distinct stages…

The strongly coupled hydrodynamic, magnetic, and radiation properties of the plasma in the solar chromosphere makes it a region of the Sun's atmosphere that is poorly understood. We use data obtained with the high-resolution Visible…

Solar flare activity is characterised by different classification systems, both in optical and X-ray ranges. The most generally accepted classifications of solar flares describe important parameters of flares such as the maximum of…

Solar and Stellar Astrophysics · Physics 2022-12-28 Elena Bruevich

Quasi-periodic oscillations in solar flaring emission have been observed over the past few decades. To date, the underpinning processes resulting in the quasi-periodic oscillations remain unknown. In this paper, we report a unique event…

Solar and Stellar Astrophysics · Physics 2024-07-08 Yining Zhang , Ting Li , Jing Ye

Searches for small exoplanets around solar-type stars are limited by stellar physical variability. While chromospheric variability is well studied, observing, modeling. and understanding the much smaller fluctuations in photospheric…

Solar and Stellar Astrophysics · Physics 2024-07-03 Dainis Dravins , Hans-Günter Ludwig

The bulk of the radiative output of a solar flare is emitted from the chromosphere, which produces enhancements in the optical and UV continuum, and in many lines, both optically thick and thin. We have, until very recently, lacked…

Solar and Stellar Astrophysics · Physics 2015-10-07 Graham S. Kerr , Paulo J. A. Simões , Jiong Qiu , Lyndsay Fletcher

We present fast cadence and high resolution observations of flare ribbons from the Solar Orbiter Extreme Ultraviolet Imager (EUI). Utilizing the short-exposure observations from the EUI High Resolution Imager in EUV (HRIEUV), we find…

Circular ribbon flares are usually related to spine-fan type magnetic topology containing null-points. In this paper, we investigate an X-class circular ribbon flare on 2012 October 23, using the multi-wavelength data from the \textit{Solar…

Solar and Stellar Astrophysics · Physics 2015-06-19 Kai Yang , Yang Guo , M. D. Ding

The chromospheric response to the input of flare energy is marked by extended extreme ultraviolet (EUV) ribbons and hard X-ray (HXR) footpoints. These are usually explained as the result of heating and bremsstrahlung emission from…

Solar and Stellar Astrophysics · Physics 2016-01-20 Paulo J. A. Simões , David R. Graham , Lyndsay Fletcher

The GOES X1 flare SOL2014-10-25T17:08:00 was a three-ribbon solar flare observed with IRIS in the near and far ultraviolet. One of the flare ribbons crossed a sunspot umbra, producing a dramatic, $\sim1000$% increase in the near-ultraviolet…

We have systematically investigated ultraviolet (UV) emission from molecular hydrogen (H$_{2}$) using the Interface Region Imaging Spectrometer (IRIS), during three X-ray flares of C5.1, C9.7 and X1.0 classes on Oct. 25, 2014. Significant…

Solar and Stellar Astrophysics · Physics 2023-09-15 Sargam M. Mulay , Lyndsay Fletcher , Hugh Hudson , Nicolas Labrosse