Search Publications
Low heat conduction in white dwarf boundary layers?
Burwitz, V.; Liu, F. K.; Meyer, F. +1 more
Context: X-ray spectra of dwarf novae in quiescence observed by Chandra and XMM-Newton provide new information on the boundary layers of their accreting white dwarfs.
Aims: Comparison of observations and models allows us to extract estimates for the thermal conductivity in the accretion layer and reach conclusions on the relevant physical proc…
A mid-infrared study of H II regions in the Magellanic Clouds: N88 A and N160 A
Tielens, A. G. G. M.; Peeters, E.; Martín-Hernández, N. L.
Aims: To show the importance of high-spatial resolution observations of H II regions when compared with observations obtained with larger apertures such as ISO, we present mid-infrared spectra of two Magellanic Cloud H II regions, N88 A and N160 A.
Methods: We obtained mid-infrared (8-13 µm), long-slit spectra with TIMMI2 on the ESO 3.6 …
Discovery, photometry, and astrometry of 49 classical nova candidates in M 81 galaxy
Garnavich, P. M.; Thilker, D. A.; Hornoch, K. +2 more
Aims: This paper reports on a search for new classical nova candidates in the M 81 galaxy based on archival, as well as recent, new images.
Methods: We used images from 1999-2007 to search for optical transients in M 81. The positions of the identified classical nova candidates were used to study their spatial distribution. Kolmogorov-Smirnov …
EUV spectral energy distribution of quasars restored from associated absorbers
Reimers, D.; Levshakov, S. A.; Agafonova, I. I. +2 more
Aims: We reconstruct the spectral shape of the quasar ionizing radiation in the extreme-UV range (1 Ryd ≤ E < 10 Ryd) from the analysis of narrow absorption lines (NAL) of the associated systems.
Methods: The computational technique for inverse spectroscopic problems - a Monte Carlo Inversion augmented by the spectral shape recovering proce…
Confirmation of the binary status of Chamaeleon Hα 2 - a very young low-mass binary in Chamaeleon
Neuhäuser, R.; Schmidt, T. O. B.; Vogt, N. +3 more
Context: Neuhäuser & Comerón (1998, Science, 282, 83; 1999, A&A, 350, 612) presented direct imaging evidence, as well as first spectra, of several young stellar and sub-stellar M6- to M8-type objects in the Cha I dark cloud. One of these objects is Cha Hα 2, classified as brown dwarf candidate in several publications and suggested as possi…
XMM-Newton X-ray and optical monitor far UV observations of NGC 7070A and ESO 2400100 shell galaxies
Marino, A.; Trinchieri, G.; Rampazzo, R. +3 more
Context: Shell galaxies are considered to be the debris of recent accretion/merging episodes. Their high frequency in low density environments suggests that these episodes could drive the secular evolution of at least some fraction of the early-type galaxy population.
Aims: We present XMM-Newton X-ray observations of two shell galaxies, NGC 70…
In situ spectroscopy of the solar corona
Li, B.; Fineschi, S.; Habbal, S. R. +1 more
Context: Future spacecraft missions, such as the proposed Solar Probe mission, will venture close to the Sun, allowing spectrometers measuring emission from heavy ions or neutrals in the solar wind to have radial lines of sight (LOS) pointing away from the Sun, or indeed in any direction other than sunwards.
Aims: We show that a radial LOS giv…
Modeling of C IV pumped fluorescence of Fe II in symbiotic stars
Nilsson, H.; Long, K. S.; Eriksson, M. +1 more
Aims:We describe how the C IV λ1548.18 line pumps the 1548.20 and 1548.41 Å channels of Fe II in symbiotic stars through the process known as photo-ionization by accidental resonance (PAR). We describe where and why Fe II fluorescence arises in symbiotic stars and whether the Fe II λ1548.41 channel can only be activated when there is a white-dwarf…
Investigation of CME dynamics in the LASCO field of view
Cho, K. -S.; Moon, Y. -J.; Shanmugaraju, A. +2 more
Context: The speed-distance profile of CMEs is important for understanding the propagation of CMEs.
Aims: Our main aim is to study the initial speed of CMEs in the LASCO field of view and its role in subsequent CME propagation using the acceleration-speed profile. The secondary aim is to obtain the speed growth rate.
Methods: We considered…
Deep surface photometry of edge-on spirals in Abell galaxy clusters. Constraining environmental effects
Santiago, B. X.; Vale, T. B.
Context: There is a clear scarcity of structural parameters for stellar thick discs, especially for spiral galaxies located in high-density regions, such as galaxy clusters and compact groups.
Aims: We have modelled the thin and thick discs of 4 edge-on spirals located in Abell clusters: NGC 705, ESO 243G49, ESO 187G19, LCSBS 0496P. Deep I ban…