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The earlier orbits and ephemerides for the Soviet satellites were not sufficiently
accurate to be very useful in making observations in Alaska. Extrapolations
from our own observations gave better predictions. This merely pointed out the fact
that rough observations of meridian transits at high latitudes will give better values
of the inclination of the orbit than precision observations at low latitudes. Hence,
it was decided to observe visually the meridian transits estimating the altitude by
noting the position with respect to the stars or using crude alidade measurements.
The times of the earlier observations were observed on a watch or clock and the clock
correction obtained from WWV. Later the times were determined with the aid of stop
watches, taking time intervals from WWV signals.
This rather meager program of optical observations of the Soviet satellites was
undertaken to give supplementary data for use of the radio observations, and particularly
to assist in the prediction of position of the satellite so that the 61-foot
radar of Stanford Research Institute could be set accurately enough to observe it
(the beam width at the half-power points is about 3°).
This report contains primarily the visual observations made at the Geophysical
Institute by various members of the staff, and a series of observations by Olaf
Halverson at Nome, Alaska. In addition there is a short discussion of the geometry
of the trajectory, the illumination of a circumpolar satellite, and a note on the
evaluation of Brouwer's moment factors.The research reported In this document has been sponsored by
the Geophysics Research Directorate of the Air Force Cambridge
Research Center* Air Research and Development Command, under
Contract AF 19(604)-3880.List of Figures -- Introduction -- Present knowledge of the electron densities and collision frequencies in the D region of the ionosphere. -- The theory of radio wave interaction. -- The outline of the planned experiment. -- Some comments about the planned experiment.
Some comments about gyrointeraction. -- Conclusion -- Acknowledgements -- ReferencesYe
Elementary excitation families and their frequency ordering in cylindrically symmetric Bose-Einstein condensates
We present a systematic classification of the elementary excitations of
Bose-Einstein condensates in cylindrical traps in terms of their shapes. The
classification generalizes the concept of families of excitations first
identified by Hutchinson and Zaremba (1998) Phys. Rev. A 57 1280 by introducing
a second classification number that allows all possible modes to be assigned to
a family. We relate the energy ordering of the modes to their family
classification, and provide a simple model which explains the relationship.Comment: 15 pages, 8 figures; abstract complemented, section 4.2 shortened,
references corrected; to be published in J. Phys.
Deduction of the quantum numbers of low-lying states of 6-nucleon systems based on symmetry
The inherent nodal structures of the wavefunctions of 6-nucleon systems have
been investigated. The existence of a group of six low-lying states dominated
by L=0 has been deduced. The spatial symmetries of these six states are found
to be mainly {4,2} and {2,2,2}.Comment: 8 pages, no figure
F-Term Hybrid Inflation Followed by a Peccei-Quinn Phase Transition
We consider a cosmological set-up, based on renormalizable superpotential
terms, in which a superheavy scale F-term hybrid inflation is followed by a
Peccei-Quinn phase transition, resolving the strong CP and mu problems of the
minimal supersymmetric standard model. We show that the field which triggers
the Peccei-Quinn phase transition can remain after inflation well above the
Peccei-Quinn scale thanks to (i) its participation in the supergravity and
logarithmic corrections during the inflationary stage and (ii) the high reheat
temperature after the same period. As a consequence, its presence influences
drastically the inflationary dynamics and the universe suffers a second period
of reheating after the Peccei-Quinn phase transition. Confronting our
inflationary predictions with the current observational data, we find that, for
about the central value of the spectral index, the grand unification scale can
be identified with its supersymmetric value for the relevant coupling constant
\kappa=0.002 and, more or less, natural values, +/-(0.01-0.1), for the
remaining parameters. On the other hand, the final reheat temeperature after
the Peccei-Quinn phase transition turns out to be low enough so as the
gravitino problem is avoided.Comment: 15 pages including 8 figures, version published in Phys. Rev.
Some notions of subharmonicity over the quaternions
This works introduces several notions of subharmonicity for real-valued
functions of one quaternionic variable. These notions are related to the theory
of slice regular quaternionic functions introduced by Gentili and Struppa in
2006. The interesting properties of these new classes of functions are studied
and applied to construct the analogs of Green's functions.Comment: 16 page
Blueprint for a Science of Mind: A Critical Notice of Christopher Peacocke's A Study of Concepts
Finite temperature properties of the Dirac operator with bag boundary conditions
We study the finite temperature free energy and fermion number for Dirac
fields in a one-dimensional spatial segment, under local boundary conditions
compatible with the presence of a spectral asymmetry. We discuss in detail the
contribution of this part of the spectrum to the determinant. We evaluate the
finite temperature properties of the theory for arbitrary values of the
chemical potential.Comment: Talk given at the Seventh International Workshop Quantum Field Theory
under the influence of External Conditions, QFEXT'05, Barcelona, Spain. Final
version, to appear in Journal of Physics A: Mathematical and Genera
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