Search Publications
Diagnostics of the κ-distribution using Si III lines in the solar transition region
Dzifčáková, E.; Kulinová, A.
Aims: The solar transition region satisfies the conditions for appearance of the non-thermal κ-distribution. We aim to prove the occurrence of the non-thermal κ-distribution in the solar transition region and diagnose its parameters.
Methods: The intensity ratios of Si iii lines observed by SUMER in 1100-1320 Å region do not correspond t…
Quiet-Sun imaging asymmetries in Na I D1 compared with other strong Fraunhofer lines
Leenaarts, J.; Carlsson, M.; Rouppe van der Voort, L. H. M. +3 more
Imaging spectroscopy of the solar atmosphere using the Na I D1 line yields marked asymmetry between the blue and red line wings: sampling a quiet-Sun area in the blue wing displays reversed granulation, whereas sampling in the red wing displays normal granulation. The Mg I b2 line of comparable strength does not show this asy…
X-ray observations of PKS 0745-191 at the virial radius: are we there yet?
Rossetti, M.; Molendi, S.; Gastaldello, F. +1 more
Aims: We reassess the properties of the ICM at large radii in the galaxy cluster PKS 0745-191 in light of recent Suzaku measurements.
Methods: We analyze an archival 10.5 ks ROSAT/PSPC observation to extract the surface-brightness profile of PKS 0745-191 and infer the deprojected density profile. We then compare the ROSAT surface-brightn…
A large Hα line forming region for the massive interacting binaries β Lyrae and υ Sagitarii
Chesneau, O.; Goldfinger, P. J.; Sturmann, J. +16 more
Aims: This study aims at constraining the properties of two interacting binary systems by measuring their continuum-forming region in the visible and the forming regions of some emission lines, in particular Hα, using optical interferometry.
Methods: We have obtained visible medium (R ~ 1000) spectral resolution interferometric observati…
Oscillatory motions observed in eruptive filaments
Koutchmy, S.; Baudin, F.; Bocchialini, K. +2 more
Context. The origin of the variable component of the solar wind is of great intrinsic interest for heliophysics and spaceweather, e.g. the initiation of coronal mass ejections and the problem of mass loss of all stars. It is also related to the physics of coronal neutral sheets and streamers, which occur above lines of magnetic polarity reversal. …
XMM-Newton observations of the superbubble in N 158 in the LMC
Haberl, F.; Sasaki, M.; Breitschwerdt, D. +1 more
Aims: We study the diffuse X-ray emission observed in the field of view of the pulsar B 0540-69 in the Large Magellanic Cloud (LMC) by XMM-Newton. We wish to understand the nature of this soft diffuse emission, which coincides with the superbubble in the H ii region N 158, and improve our understanding of the evolution of superbubbles.
M…
A pan-chromatic view of the galaxy cluster XMMU J1230.3+1339 at z = 0.975. Observing the assembly of a massive system
Böhringer, H.; Pratt, G. W.; Rovilos, E. +16 more
Context. Observations of the formation and evolution of massive galaxy clusters and their matter components provide crucial constraints on cosmic structure formation, the thermal history of the intracluster medium (ICM), galaxy evolution, transformation processes, and gravitational and hydrodynamic interaction physics of the subcomponents.
Ai…
The EUV spectrum of the Sun: SOHO CDS NIS irradiances from 1998 until 2010
Andretta, V.; Del Zanna, G.
We present extreme-ultraviolet (EUV) irradiances of the Sun taken during the 1998-2010 period from the Solar and Heliospheric Observatory (SoHO) Coronal Diagnostic Spectrometer (CDS) Normal Incidence Spectrograph (NIS). They were obtained from NIS full-Sun radiance observations, and represent the first set of EUV spectral observations spanning a s…
Evolution of the dust coma in comet 67P/Churyumov-Gerasimenko before the 2009 perihelion
Vincent, J. -B.; Schulz, R.; Licandro, J. +5 more
Context. Comet 67P/Churyumov-Gerasimenko is the main target of ESA's Rosetta mission and will be encountered in May 2014. Because the spacecraft will orbit the comet nucleus before and after release of the lander Philae, it is necessary to know the conditions in the coma.
Aims: We study the dust environment, including the dust production rate…
On the origin of correlated X-ray/VHE emission from LS I +61 303
Paredes, J. M.; Zabalza, V.; Bosch-Ramon, V.
Context. The MAGIC collaboration recently reported correlated X-ray and very high-energy (VHE) gamma-ray emission from the gamma-ray binary LS I +61 303 during ~60% of one orbit. These observations suggest that the emission in these two bands has its origin in a single particle population.
Aims: We aim at improving our understanding of the so…