Search Publications
Opposition effect on comet 67P/Churyumov-Gerasimenko using Rosetta-OSIRIS images
Jorda, L.; Lamy, P. L.; Lara, L. M. +46 more
Aims: We aim to explore the behavior of the opposition effect as an important tool in optical remote sensing on the nucleus of comet 67P/ Churyumov-Gerasimenko (67P), using Rosetta-OSIRIS images acquired in different filters during the approach phase, July-August 2014 and the close flyby images on 14 of February 2015, which contain the spacec…
Imaging Observations of Magnetic Reconnection in a Solar Eruptive Flare
Sun, X.; Ding, M. D.; Li, Y. +2 more
Solar flares are among the most energetic events in the solar atmosphere. It is widely accepted that flares are powered by magnetic reconnection in the corona. An eruptive flare is usually accompanied by a coronal mass ejection, both of which are probably driven by the eruption of a magnetic flux rope (MFR). Here we report an eruptive flare on 201…
Detection of the high-energy cut-off from the Seyfert 1.5 galaxy NGC 5273
Misra, R.; Dewangan, G. C.; McHardy, I. M. +2 more
We perform the NuSTAR and Swift/XRT joint energy spectral fitting of simultaneous observations from the broad-line Seyfert 1.5 galaxy NGC 5273. When fitted with the combination of an exponential cut-off power law and a reflection model, a high-energy cut-off is detected at 143^{+96}_{-40} keV with 2σ significance. Existence of such cut-off is also…
The spatially resolved stellar population and ionized gas properties in the merger LIRG NGC 2623
Villar-Martín, M.; Roth, M. M.; González Delgado, R. M. +10 more
We report on a detailed study of the stellar populations and ionized gas properties in the merger LIRG NGC 2623, analyzing optical integral field spectroscopy from the CALIFA survey and PMAS LArr, multiwavelength HST imaging, and OSIRIS narrow band Hα and [NII]λ6584 imaging. The spectra were processed with the starlight full spectral fitting code,…
Review of Image Quality Measures for Solar Imaging
Popowicz, Adam; Bernacki, Krzysztof; Orlov, Valeri +1 more
Observations of the solar photosphere from the ground encounter significant problems caused by Earth's turbulent atmosphere. Before image reconstruction techniques can be applied, the frames obtained in the most favorable atmospheric conditions (the so-called lucky frames) have to be carefully selected. However, estimating the quality of images co…
Martian ionosphere observed by Mars Express. 2. Influence of solar irradiance on upper ionosphere and escape fluxes
Barabash, S.; Pätzold, M.; Dubinin, E. +4 more
We present multi-instrument observations of the effects of solar irradiance on the upper Martian ionosphere and escape fluxes based on Mars Express measurements obtained over almost 12 years. It is shown that the variations in the upper ionosphere caused by solar irradiance lead to significant changes in the trans-terminator fluxes of low-energy i…
A hybrid approach to empirical magnetosphere modeling
Tsyganenko, N. A.; Andreeva, V. A.
A new approach has been devised and explored to reconstruct magnetospheric configurations, based on spacecraft data and a synthesis of two methods of modeling the magnetic field of extraterrestrial currents. The main idea is to combine within a single framework (1) a modular structure explicitly representing separate contributions to the total fie…
A 1.4 deg2 blind survey for C II], C III] and C IV at z ∼ 0.7-1.5 - I. Nature, morphologies and equivalent widths
Sobral, David; Matthee, Jorryt; Stroe, Andra +2 more
While traditionally associated with active galactic nuclei (AGN), the properties of the C II] (λ = 2326 Å), C III] (λ, λ = 1907, 1909 Å) and C IV (λ, λ = 1549, 1551 Å) emission lines are still uncertain as large, unbiased samples of sources are scarce. We present the first blind, statistical study of C II], C III] and C IV emitters at z ∼ 0.68, 1.…
Comparing UV/EUV line parameters and magnetic field in a quiescent prominence with tornadoes
Fletcher, L.; Schmieder, B.; Labrosse, N. +2 more
Context. Understanding the relationship between plasma and the magnetic field is important for describing and explaining the observed dynamics of solar prominences.
Aims: We determine if a close relationship can be found between plasma and magnetic field parameters, measured at high resolution in a well-observed prominence.
Methods: A pr…
Coronal Jets Simulated with the Global Alfvén Wave Solar Model
Gombosi, T. I.; Toth, G.; Antiochos, S. K. +5 more
This paper describes a numerical modeling study of coronal jets to understand their effects on the global corona and their contribution to the solar wind. We implement jets into a well-established three-dimensional, two-temperature magnetohydrodynamic (MHD) solar corona model employing Alfvén-wave dissipation to produce a realistic solar-wind back…