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The tensor part of the Skyrme energy density functional. III. Time-odd terms at high spin
This article extends previous studies on the effect of tensor terms in the
Skyrme energy density functional by breaking of time-reversal invariance. We
have systematically probed the impact of tensor terms on properties of
superdeformed rotational bands calculated within the cranked
Hartree-Fock-Bogoliubov approach for different parameterizations covering a
wide range of values for the isoscalar and isovector tensor coupling constants.
We analyze in detail the contribution of the tensor terms to the energies and
dynamical moments of inertia and study their impact on quasi-particle spectra.
Special attention is devoted to the time-odd tensor terms, the effect of
variations of their coupling constants and finite-size instabilities.Comment: 28 pages, 34 figure
An Investigation of Be/X-ray Pulsars with OGLE-III Data
We have studied five seasons of OGLE-III data for eight SMC Be/X-ray pulsars
for which no other survey data were available. We have determined orbital
periods for four of these binary systems, one of which also shows nonradial
pulsations. Optical identification of SMC X-2 is reconsidered, but no periods
were found for either of the two possible candidates
Time-odd mean fields in covariant density functional theory: Rotating systems
Time-odd mean fields (nuclear magnetism) and their impact on physical
observables in rotating nuclei are studied in the framework of covariant
density functional theory (CDFT). It is shown that they have profound effect on
the dynamic and kinematic moments of inertia. Particle number, configuration
and rotational frequency dependences of their impact on the moments of inertia
have been analysed in a systematic way. Nuclear magnetism can also considerably
modify the band crossing features such as crossing frequencies and the
properties of the kinematic and dynamic moments of inertia in the band crossing
region. The impact of time-odd mean fields on the moments of inertia in the
regions away from band crossing only weakly depends on the relativistic mean
field parametrization, reflecting good localization of the properties of
time-odd mean fields in CDFT. The moments of inertia of normal-deformed nuclei
considerably deviate from the rigid body value. On the contrary, superdeformed
and hyperdeformed nuclei have the moments of inertia which are close to rigid
body value. The structure of the currents in rotating frame, their microscopic
origin and the relations to the moments of inertia have been systematically
analysed. The phenomenon of signature separation in odd-odd nuclei, induced by
time-odd mean fields, has been analysed in detail.Comment: 20 pages. 16 figure
Modelling the Galactic Bar Using Red Clump Giants
The color-magnitude diagrams of stars obtained for 12
fields across the Galactic bulge with the OGLE project reveal a well-defined
population of bulge red clump giants. We find that the distributions of the
apparent magnitudes of the red clump stars are systematically fainter when
moving towards lower galactic fields. The most plausible explanation of
this distinct trend is that the Galactic bulge is a bar, whose nearest end lies
at positive galactic longitude. We model this Galactic bar by fitting for all
fields the observed luminosity functions in the red clump region of the
color-magnitude diagram. We find that almost regardless of the analytical
function used to describe the 3-D stars distribution of the Galactic bar, the
resulting models have the major axis inclined to the line of sight by
, with axis ratios corresponding to . This
puts a strong constraint on the possible range of the Galactic bar models.
Gravitational microlensing can provide us with additional constrains on the
structure of the Galactic bar.Comment: submitted to the New Astronomy, 27 pages, 11 figures; also available
at ftp://www.astro.princeton.edu/stanek/Barmodel and through WWW at
http://www.astro.princeton.edu/~library/prep.htm
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