English
Related papers

Related papers: On the Lyman-alpha and Lyman-beta lines in solar c…

200 papers

The hydrogen Lyman-alpha plays a dominant role in the radiative energy transport in the lower transition region, and is important for the stud- ies of transition-region structure as well as solar wind origin. We investigate the Ly-alpha…

Solar and Stellar Astrophysics · Physics 2014-11-20 Hui Tian , Luca Teriaca , Werner Curdt , Jean-Claude Vial

The solar radiation in the Lyman-alpha spectral line of hydrogen plays a significant role in the illumination of chromospheric and coronal structures, such as prominences, spicules, chromospheric fibrils, cores of coronal mass ejections,…

Solar and Stellar Astrophysics · Physics 2020-12-16 S. Gunar , P. Schwartz , J. Koza , P. Heinzel

The profiles of emission lines formed in the corona contain information on the dynamics and the heating of the hot plasma. Only recently has data with sufficiently high spectral resolution become available for investigating the details of…

Solar and Stellar Astrophysics · Physics 2015-05-18 H. Peter

We use state-of-the-art radiation-MHD simulations and 3D non-LTE radiative transfer computations to investigate \Halpha\ line formation in the solar chromosphere and apply the results of this investigation to develop the potential of…

Solar and Stellar Astrophysics · Physics 2015-06-04 Jorrit Leenaarts , Mats Carlsson , Luc Rouppe van der Voort

We study the hydrogen Lyman emission in various solar features - now including Lyman-alpha observations free from geocoronal absorption - and investigate statistically the imprint of flows and of the magnetic field on the line profile and…

Solar and Stellar Astrophysics · Physics 2015-03-17 Werner Curdt , Hui Tian , Eckart Marsch

The hydrogen Lyman lines ( 91.2 nm < lambda < 121.6 nm) are significant contributors to the radiative losses of the solar chromosphere, and are enhanced during flares. We have shown previously that the Lyman lines observed by the Extreme…

Solar and Stellar Astrophysics · Physics 2018-08-08 Stephen A Brown , Lyndsay Fletcher , Graham S Kerr , Nicolas Labrosse , Adam F Kowalski , Jaime De La Cruz Rodríguez

The Hydrogen Balmer series is a basic radiative loss channel from the flaring solar chromosphere. We report here on the analysis of an extremely rare set of simultaneous observations of a solar flare in the H${\alpha}$ and H${\beta}$ lines…

Since the Lalpha rocket observations of (Gabriel, Solar Phys. 21, 392, 1971), it has been realized that the hydrogen (H) lines could be observed in the corona and offer an interesting diagnostic for the temperature, density, and radial…

Solar and Stellar Astrophysics · Physics 2016-11-15 Jean-Claude Vial , Martine Chane-Yook

An analysis of Lyman series lines arising from hydrogen-like oxygen and neon ions in the coronae of the active RS CVn-type binaries II Peg and IM Peg, observed using the {\it Chandra} High Resolution Transmission Grating Spectrograph, shows…

Astrophysics · Physics 2009-11-10 Paola Testa , Jeremy J. Drake , Giovanni Peres , Edward E. DeLuca

We extend earlier work by studying in the quiet Sun the line profiles of the hydrogen Lyman-alpha and Lyman-beta lines, which were obtained quasi-simultaneously in a raster scan near disk center. The self-reversal depths of the Ly-a and…

Solar and Stellar Astrophysics · Physics 2009-09-10 H. Tian , W. Curdt , E. Marsch , U. Schuehle

Helmet streamers are a prominent manifestation of magnetic structures with current sheets in the solar corona. These large-scale structures are regions with high plasma density, overlying active regions and filament channels. We investigate…

Solar and Stellar Astrophysics · Physics 2019-10-04 Bieke Decraemer , Andrei N. Zhukov , Tom Van Doorsselaere

Recent studies of interstellar neutral (ISN) hydrogen observed by the Interstellar Boundary Explorer (IBEX) suggested that the present understanding of the radiation pressure acting on hydrogen atoms in the heliosphere should be revised.…

Solar and Stellar Astrophysics · Physics 2018-02-05 Izabela Kowalska-Leszczynska , Maciej Bzowski , Justyna M. Sokół , Marzena A. Kubiak

Wide-field EUV telescopes imaging in spectral bands sensitive to 1 MK plasma on the Sun often observe extended ray-like coronal structures stretching radially from active regions to distances of 1.5-2Rsun, which represent the EUV…

Solar and Stellar Astrophysics · Physics 2014-01-24 F. Goryaev , V. Slemzin , L. Vainshtein , D. R. Williams

We investigate the role of non-thermal electrons in the formation regions of Halpha, Hbeta, and Hgamma lines in order to unfold their influence on the formation of these lines. We concentrate on pulse-beam heating varying on a subsecond…

Solar and Stellar Astrophysics · Physics 2015-05-13 J. Kasparova , M. Varady , P. Heinzel , M. Karlicky , Z. Moravec

We show how the observed hydrogen Balmer and Lyman emission lines constrain the modeling of quiescent solar prominences. We compare space observations of Lyman lines with ground-based observations of Balmer lines for quiescent solar…

Solar and Stellar Astrophysics · Physics 2012-10-03 G. Stellmacher , E. Wiehr

The hydrogen Lyman-$\alpha$ (H {\sc i} Ly$\alpha$) emission during solar flares has rarely been studied in spatially resolved images and its physical origin has not been fully understood. In this paper, we present novel Ly$\alpha$ images…

Solar and Stellar Astrophysics · Physics 2022-09-21 Ying Li , Qiao Li , De-Chao Song , Andrea Francesco Battaglia , Hualin Xiao , Säm Krucker , Udo Schühle , Hui Li , Weiqun Gan , M. D. Ding

The quiet solar corona emits meter-wave thermal bremsstrahlung. Coronal radio emission can only propagate above that radius, $R_\omega$, where the local plasma frequency eqals the observing frequency. The radio interferometer LOw Frequency…

Solar and Stellar Astrophysics · Physics 2018-06-13 C. Vocks , G. Mann , F. Breitling , M. M. Bisi , B. Dabrowski , R. Fallows , P. T. Gallagher , A. Krankowski , J. Magdalenic , C. Marque , D. Morosan , H. Rucker

Aims. We investigate the effect of the electric return currents in solar flares on the profiles of hydrogen Balmer lines. We consider the monoenergetic approximation for the primary beam and runaway model of the neutralizing return current.…

Astrophysics · Physics 2009-11-13 Jiri Stepan , Jana Kasparova , Marian Karlicky , Petr Heinzel

Ultraviolet spectroscopy of the extended solar corona is a powerful tool for measuring the properties of protons, electrons, and heavy ions in the accelerating solar wind. The large coronal holes that expand up from the north and south…

Solar and Stellar Astrophysics · Physics 2020-07-28 Steven R. Cranmer

Characterising the large-scale structure and plasma properties of the inner corona is crucial to understand the source and subsequent expansion of the solar wind and related space weather effects. Here we apply a new coronal rotational…

Solar and Stellar Astrophysics · Physics 2020-04-22 Huw Morgan , Anthony C. Cook
‹ Prev 1 2 3 10 Next ›