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Related papers: H-alpha features with hot onsets. I. Ellerman bomb…

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Deep H$\alpha$ images of a faint emission complex 4.0 x 5.5 degrees in angular extent and located far off the Galactic plane at l = 70.0 degrees, b=-21.5 degrees reveal numerous thin filaments suggestive of a supernova remnant's shock…

High Energy Astrophysical Phenomena · Physics 2015-10-14 Robert Fesen , Jack Neustadt , Christine Black , Ari Koeppel

We study the H$\alpha$ and Ca II 8542 \r{A} line spectra of four typical Ellerman bombs (EBs) in active region NOAA 11765 on 2013 June 6, observed with the Fast Imaging Solar Spectrograph installed at the 1.6 meter New Solar Telescope at…

Solar and Stellar Astrophysics · Physics 2014-08-12 Jie Hong , M. D. Ding , Ying Li , Cheng Fang , Wenda Cao

Ellerman bombs (EBs) and UV bursts are both brightenings related to flux emergence regions and specifically to magnetic flux of opposite polarity that meet in the photosphere. These two reconnection-related phenomena, nominally formed far…

Solar and Stellar Astrophysics · Physics 2019-06-19 V. Hansteen , A. Ortiz , V. Archontis , M. Carlsson , T. M. D. Pereira , J. P. Bjørgen

Context. Ellerman bombs (EBs) are short-lived emission features, characterized by extended wing emission in hydrogen Balmer lines. Until now, no distinct signature of EBs has been found in the He I 10830 {\AA} line, and conclusive…

Solar and Stellar Astrophysics · Physics 2017-02-01 Tine Libbrecht , Jayant Joshi , Jaime de la Cruz Rodríguez , Jorrit Leenaarts , Andrés Asensio Ramos

(abridged) The heating mechanism at high densities during M dwarf flares is poorly understood. Spectra of M dwarf flares in the optical and near-ultraviolet wavelength regimes have revealed three continuum components during the impulsive…

Solar and Stellar Astrophysics · Physics 2015-06-23 Adam F. Kowalski , Suzanne L. Hawley , Mats Carlsson , Joel C. Allred , Han Uitenbroek , Rachel A. Osten , Gordon Holman

High cadence, multiwavelength, optical observations of a solar active region are presented, obtained with the Swedish Solar Telescope. Two magnetic bright points are seen to separate in opposite directions at a constant velocity of 2.8km/s.…

Solar and Stellar Astrophysics · Physics 2015-05-18 D. B. Jess , M. Mathioudakis , P. K. Browning , P. J. Crockett , F. P. Keenan

Optical emission lines provide an important new window on the HVCs. Recent studies of the H-alpha line reveal that ionized gas is pervasively associated with the neutral hydrogen in HVCs. The Wisconsin H-Alpha Mapper (WHAM) instrument has…

Astrophysics · Physics 2007-05-23 S. L. Tufte , R. J. Reynolds , L. M. Haffner

During the initial data reduction of the Wisconsin H-Alpha Mapper (WHAM) H-Alpha Sky Survey, we have discovered several very long (~30--80 deg) filaments superimposed on the diffuse H-Alpha background. These features have no clear…

Astrophysics · Physics 2009-10-30 L. M. Haffner , R. J. Reynolds , S. L. Tufte

Spectroscopic observations of the low luminosity Seyfert 1 nucleus in NGC 3516 obtained with the Hubble Space Telescope show that the visible spectrum is dominated by the Balmer emission lines of Hydrogen (H) and a continuum luminosity that…

Astrophysics of Galaxies · Physics 2016-05-25 Nick Devereux

We use observations of quiet Sun (QS) regions in the H$\alpha$ 6563 \AA, Ca~{\sc ii} 8542 \AA\, and Fe~{\sc i} 6302 \AA\ lines. We observe brightenings in the wings of the H$\alpha$ and Ca~{\sc ii} combined with observations of the…

Solar and Stellar Astrophysics · Physics 2018-12-19 J. Shetye , S. Shelyag , A. L. Reid , E. Scullion , J. G. Doyle , T. D. Arber

Context. Ellerman bombs (EBs) are observational signatures of small-scale magnetic reconnection, key to understanding the lower solar atmosphere. While their role in active regions has been widely studied using the H$\alpha$ line,…

Solar and Stellar Astrophysics · Physics 2026-05-06 I. J. Soler Poquet , C. J. Díaz Baso , A. Sainz Dalda , L. H. M. Rouppe van der Voort , D. Nóbrega-Siverio , R. Joshi

The detection and first identification of the deuterium Balmer emission lines, D-alpha and D-beta, in the core of the Orion Nebula is reported. Observations were conducted at the 3.6m Canada-France-Hawaii Telescope, using the Echelle…

Astrophysics · Physics 2007-05-23 G. Hebrard , D. Pequignot , A. Vidal-Madjar , J. R. Walsh , R. Ferlet

An analysis of H alpha and H beta spectra in a sample of 30 cool dwarf and subgiant stars is presented using MARCS model atmospheres based on the most recent calculations of the line opacities. A detailed quantitative comparison of the…

The Wisconsin H-Alpha Mapper (WHAM) Northern Sky Survey is revealing that many intermediate-velocity (|v_LSR| <= 100 km/s) neutral clouds and complexes have an associated ionized component. We present the first map of the H-Alpha emission…

Astrophysics · Physics 2009-11-06 L. M. Haffner , R. J. Reynolds , S. L. Tufte

Ellerman Bomb-like brightenings of the hydrogen Balmer line wings in the quiet Sun (QSEBs) are a signature of the fundamental process of magnetic reconnection at the smallest observable scale in the solar lower atmosphere. We analyze high…

Solar and Stellar Astrophysics · Physics 2020-09-09 Jayant Joshi , Luc H. M. Rouppe van der Voort , Jaime de la Cruz Rodríguez

The focus of this investigation is to quantify the conversion of magnetic to thermal energy initiated by a quiet Sun cancellation event and to explore the resulting dynamics from the interaction of the opposite polarity magnetic features.…

Solar and Stellar Astrophysics · Physics 2023-03-29 Anjali. J. Kaithakkal , J. M. Borrero , A. Pastor Yabar , J. de la Cruz Rodríguez

Quiet Sun Ellerman Bombs (QSEBs) are key indicators of small-scale photospheric magnetic reconnection events. Recent high-resolution observations have shown that they are ubiquitous and that large numbers of QSEBs can be found in the quiet…

Solar and Stellar Astrophysics · Physics 2024-09-11 Aditi Bhatnagar , Luc Rouppe van der Voort , Jayant Joshi

Explosive transient events occur throughout the solar atmosphere. The differing manifestations range from coronal mass ejections to Ellerman bombs. The former may have negligible signatures in the lower atmosphere, and the latter may have…

Solar and Stellar Astrophysics · Physics 2024-08-06 L. P. Chitta , I. G. Hannah , L. Fletcher , H. S. Hudson , P. R. Young , S. Krucker , H. Peter

We present the first observation of a solar prominence at $84-116$ GHz using the high resolution interferometric imaging of ALMA. Simultaneous observations in H$\alpha$ from Bia{\l}kaw Observatory and with SDO/AIA reveal similar prominence…

The term "ultraviolet (UV) burst" is introduced to describe small, intense, transient brightenings in ultraviolet images of solar active regions. We inventorize their properties and provide a definition based on image sequences in…