Search Publications
Synthetic differential emission measure curves of prominence fine structures. II. The SoHO/SUMER prominence of 8 June 2004
Heinzel, P.; Vial, J. -C.; Anzer, U. +2 more
Aims: This study is the first attempt to combine the prominence observations in Lyman, UV, and EUV lines with the determination of the prominence differential emission measure derived using two different techniques, one based on the inversion of the observed UV and EUV lines and the other employing 2D non-LTE prominence fine-structure modelin…
Extended dust shell of the carbon star U Hydrae observed with AKARI
Izumiura, H.; Matsunaga, N.; Tanabé, T. +8 more
Context. Low- to intermediate-mass stars lose a significant fraction of their mass while they are on the asymptotic giant branch (AGB). This mass loss is considered to determine the final stages of their evolution. The material ejected from the stellar photosphere forms a circumstellar envelope in its surroundings. Layers of circumstellar envelope…
Astrometry with the MCAO instrument MAD. An analysis of single-epoch data obtained in the layer-oriented mode
Kürster, M.; Rix, H. -W.; Arcidiacono, C. +2 more
Context. Current instrument developments at the largest telescopes worldwide involve the installation of multi-conjugated adaptive optics (MCAO) modules. The large field of view and more uniform correction provided by these systems is not only highly beneficial for photometric studies but also for astrometric analysis of, e.g., large dense cluster…
Structure of the outer layers of cool standard stars
Blommaert, J. A. D. L.; Eriksson, K.; Dowell, C. D. +6 more
Context. Among late-type red giants, an interesting change occurs in the structure of the outer atmospheric layers as one moves to later spectral types in the Hertzsprung-Russell diagram: a chromosphere is always present, but the coronal emission diminishes and a cool massive wind steps in.
Aims: Where most studies have focussed on short-wave…
CoRoT light curves of Blazhko RR Lyrae stars. Evidence of a strong correlation between phase and amplitude modulations of CoRoT ID 0105288363
Auvergne, M.; Baglin, A.; Bono, G. +4 more
Context. The CoRoT - Convection Rotation and planetary Transits - space mission provides a unique opportunity to monitor RR Lyrae stars with excellent time-sampling, unprecedented photometric precision, and a long time base of 150 days.
Aims: The pulsation characteristics of RR Lyrae stars rely on robust physics, but we still lack a firm quan…
Long-period oscillations of millimeter emission above sunspots
Riehokainen, A.; Kallunki, J.; Smirnova, V. +2 more
Aims: The investigation of long quasi-periodic oscillations in sunspots/active regions based on millimeter radio data was the main goal of this work.
Methods: Data from simultaneous monitoring observations of solar active regions at 37 GHz and 93 GHz at two different ground-based radio telescopes were obtained. We analyzed them with the …
MAD about the Large Magellanic Cloud. Preparing for the era of Extremely Large Telescopes
Cignoni, M.; Valenti, E.; Fiorentino, G. +3 more
We present J,H,Ks photometry from the the Multi conjugate Adaptive optics Demonstrator (MAD), a visitor instrument at the VLT, of a resolved stellar population in a small crowded field in the bar of the Large Magellanic Cloud near the globular cluster NGC 1928. In a total exposure time of 6, 36 and 20 min, magnitude limits were achieved…
AX J1910.7+0917 and three newly discovered INTEGRAL sources
Stella, L.; Walter, R.; Ferrigno, C. +4 more
Aims: We take advantage of the high sensitivity of the IBIS/ISGRI telescope and the improvements in the data analysis software to investigate the nature of the still poorly known X-ray source AX J1910.7+0917, and search for closeby previously undetected objects.
Methods: We analyze all publicly available INTEGRAL data of AX J1910.7+0917,…
The last dance of the bashful ballerina?
Mursula, K.; Virtanen, I.
Aims: The heliospheric magnetic field (HMF) has long been hemispherically asymmetric so that the field in the northern hemisphere is weaker and the area larger than in the south. This asymmetry, also called the bashful ballerina, has existed during roughly three-year intervals of the late declining to minimum phase of solar cycles 16-22. We s…
The high-velocity cloud complex Galactic center negative as seen by EBHIS and GASS. I. Cloud catalog and global properties
Kerp, J.; Winkel, B.; Flöer, L. +3 more
Using Milky Way data of the new Effelsberg-Bonn H i Survey (EBHIS) and the Galactic All-Sky Survey (GASS), we present a revised picture of the high-velocity cloud (HVC) complex Galactic center negative (GCN). Owing to the higher angular resolution of these surveys compared to previous studies (e.g., the Leiden Dwingeloo Survey), we resolve complex…