5,134 research outputs found
LOW-MASS X-RAY BINARIES AND THEIR RELATION TO THE NON-X-RAY SOURCES
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/73252/1/j.1749-6632.1977.tb37032.x.pd
X-ray Pulsations in the Supersoft X-ray Binary CAL 83
X-ray data reveal that the supersoft X-ray binary CAL 83 exhibits 38.4 minute
pulsations at some epochs. These X-ray variations are similar to those found in
some novae and are likely to be caused by nonradial pulsations the white dwarf.
This is the first detection of pulsations in a classical supersoft X-ray
binary.Comment: revised text; 11 pages and 3 figures; accepted for publication in the
Astronomical Journa
Model of two-fluid reconnection
A theoretical model of quasi-stationary, two-dimensional magnetic
reconnection is presented in the framework of incompressible two-fluid
magnetohydrodynamics (MHD). The results are compared with recent numerical
simulations and experiment.Comment: 4 pages, 1 figure, accepted to Physical Review Letter
The Core-Wing Anomaly of Cool Ap Stars: Abnormal Balmer Profiles
Paper by Cowley et al. The Core-Wing Anomaly Etc. The profiles of H
in a number of cool Ap stars are anomalous. Broad wings, indicative of
temperatures in the range 7000-8000K end abruptly in narrow cores. The widths
of these cores are compatible with those of dwarfs with temperatures of 6000K
or lower. This profile has been known for Przybylski's star, but it is seen in
other cool Ap's. The H profile in several of these stars shows a similar
core-wing anomaly (CWA). In Przybylski's star, the CWA is probably present at
higher Balmer members. We are unable to account for these profiles within the
context of LTE and normal dwarf atmospheres. We conclude that the atmospheres
of these stars are not ``normal.'' This is contrary to a notion that has long
been held.Comment: 4 Pages 5 Figures. Submitted to Astronomy and Astrophysics 4 Dec.
200
Density pattern in supercritical flow of liquid He-4
A density functional theory is used to investigate the instability arising in
superfluid He as it flows at velocity u just above the Landau critical
velocity of rotons v_c. Confirming an early theoretical prediction by one of us
[JETP Lett. 39, 511 (1984)], we find that a stationary periodic modulation of
the density occurs, with amplitude proportional to (u-v_c)^{1/2} and wave
vector equal to the roton wave vector. This density pattern is studied for
supercritical flow both in bulk helium and in a channel of nanometer
cross-section.Comment: 4 pages, 6 figures. Submitted to Phys. Rev.
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