Results 131 to 140 of about 270 (168)
Some of the next articles are maybe not open access.
An ancient nova shell around the dwarf nova Z Camelopardalis
Nature, 2007Cataclysmic variables (classical novae and dwarf novae) are binary star systems in which a red dwarf transfers hydrogen-rich matter, by way of an accretion disk, to its white dwarf companion. In dwarf novae, an instability is believed to episodically dump much of the accretion disk onto the white dwarf.
Shara, Michael M. +15 more
openaire +3 more sources
Recent Observations of Dwarf Novae
International Astronomical Union Colloquium, 1979A supermaximum of VW Hydri was observed at the ESO site from Oct. 26 until Nov. 9» 1978. High time resolution polarimetrie and spectroscopic measurements have been obtained. This paper reports on some preliminary results.
R. Schoembs, N. Vogt
openaire +1 more source
Exposed white dwarfs in dwarf novae
2008Hubble Space Telescope far ultraviolet spectroscopic observations of cataclysmic variable white dwarfs, exposed during dwarf nova quiescence, have yielded a number of new insights on accretional heating, photospheric abundances of the accreted atmosphere and rotational velocities of the underlying degenerates.
openaire +1 more source
1985
It is now well established that the eruptions characteristic of dwarf novae result from changes in the luminosity of the accretion disc centred around the white dwarf component of these systems. These luminosity variations are most successfully accounted for by variations in the accretion flow through the disc but the mechanism responsible for this ...
openaire +1 more source
It is now well established that the eruptions characteristic of dwarf novae result from changes in the luminosity of the accretion disc centred around the white dwarf component of these systems. These luminosity variations are most successfully accounted for by variations in the accretion flow through the disc but the mechanism responsible for this ...
openaire +1 more source
Publications of the Astronomical Society of Australia, 1974
The object EX Hya is a dwarf nova with a binary period of 98.3 min (Mumford 1964, 1967). Warner (1972, 1973a) has observed two complete cycles of this star with a photoelectric time resolution of 5 sec. These observations suggested that EX Hya can be understood in terms of the model proposed by Warner and Nather (1971) in their discussion of U Gem.
R. D. Watson, P. T. Rayner
openaire +1 more source
The object EX Hya is a dwarf nova with a binary period of 98.3 min (Mumford 1964, 1967). Warner (1972, 1973a) has observed two complete cycles of this star with a photoelectric time resolution of 5 sec. These observations suggested that EX Hya can be understood in terms of the model proposed by Warner and Nather (1971) in their discussion of U Gem.
R. D. Watson, P. T. Rayner
openaire +1 more source
Astrophysics, 1999
In searchs for flare stars in the vicinity of the Pleiades cluster, three flares were detected in 1970,1972, and 1977 in a star with the coordinates α1950= 3h48m·9, δl950= 25‡15’.8. The star’s brightness at a minimum is >21m·5. The star was tentatively assigned to the U Gem type.
E. A. Parsamian +2 more
openaire +1 more source
In searchs for flare stars in the vicinity of the Pleiades cluster, three flares were detected in 1970,1972, and 1977 in a star with the coordinates α1950= 3h48m·9, δl950= 25‡15’.8. The star’s brightness at a minimum is >21m·5. The star was tentatively assigned to the U Gem type.
E. A. Parsamian +2 more
openaire +1 more source
Nova and Dwarf Nova Observations with MAGIC
2016Starting in fall 2012, the MAGIC collaboration conducted a nova follow-up program in order to detect a possible VHE gamma-ray component. The program responded to Fermi-LAT detections of different types of novae at GeV energies: it initially focussed on symbiotic novae and later extended to bright Classical Novae and additional outbursts from other ...
openaire +1 more source
1995
Our survey of faint DNe is carried out using the facilities of the ESO and Asiago Observatories.
R. U. Claudi, A. Bianchini
openaire +1 more source
Our survey of faint DNe is carried out using the facilities of the ESO and Asiago Observatories.
R. U. Claudi, A. Bianchini
openaire +1 more source
Spectroscopic Observations of Dwarf Novae
International Astronomical Union Colloquium, 1979Abstract.Dwarf novae spectroscopic work is briefly reviewed and the radiation emitted by the components of the system is discussed. The reasons why the broad, shallow absorption lines arise in the disc, and not in the white dwarf, are assembled.
J.A.J. Whelan, M.W. Rayne, C.C. Brunt
openaire +1 more source
Publications of the Astronomical Society of the Pacific, 2000
We have carried out a synthetic spectral analysis of five IUE NEWSIPS archival spectra of the peculiar, very active dwarf nova CN Orionis taken at the system's lowest flux levels during quiescence. AAVSO data indicate the visual magnitude V ~ 14 for CN Ori at this time.
J. Urban +5 more
openaire +1 more source
We have carried out a synthetic spectral analysis of five IUE NEWSIPS archival spectra of the peculiar, very active dwarf nova CN Orionis taken at the system's lowest flux levels during quiescence. AAVSO data indicate the visual magnitude V ~ 14 for CN Ori at this time.
J. Urban +5 more
openaire +1 more source