5,474 research outputs found
Accurate and efficient gravitational waveforms for certain galactic compact binaries
Stellar-mass compact binaries in eccentric orbits are almost guaranteed
sources of gravitational waves for Laser Interferometer Space Antenna. We
present a prescription to compute accurate and efficient gravitational-wave
polarizations associated with bound compact binaries of arbitrary eccentricity
and mass ratio moving in slowly precessing orbits. We compare our approach with
those existing in the literature and present its advantages.Comment: 10 pages, 7 figures, to be published in MNRA
Propulsion systems dispersion analysis and optimum propellant management
Propulsion systems dispersion analysis and propellant optimization method for Apollo subsystem
Numerical Analyses of Weakly Nonlinear Velocity-Density Coupling
We study evolution of various statistical quantities of smoothed cosmic
density and velocity fields using N-body simulations. The parameter
characterizes nonlinear coupling of
these two fields and determines behavior of bulk velocity dispersion as a
function of local density contrast.
It is found that this parameter depends strongly on the smoothing scale even
in quasi-linear regimes where the skewness parameter
is nearly constant and close to the predicted value by the second-order
perturbation theory. We also analyze weakly nonlinear effects caused by an
adaptive smoothing known as the gather approach.Comment: 22 pages, 4 figures, to appear in ApJ (558, Sep 10
Thermal leptogenesis in a supersymmetric neutrinophilic Higgs model
We investigate thermal leptogenesis in a supersymmetric neutrinophilic Higgs
model by taking phenomenological constraints into account, where, in addition
to the minimal supersymmetric standard model, we introduce an extra Higgs field
with a tiny vacuum expectation value (VEV) which generates neutrino masses.
Thanks to this tiny VEV of the neutrinophilic Higgs, our model allows to reduce
the mass of the lightest right-handed (s)neutrino to be GeV as
keeping sufficiently large CP asymmetry in its decay. Therefore, the reheating
temperature after inflation is not necessarily high, hence this scenario is
free from gravitino problem.Comment: 5 pages, 1 figur
Apollo cryogenic integrated systems program
The integrated systems program is capable of simulating both nominal and anomalous operation of the Apollo cryogenics storage system (CSS). Two versions of the program exist; one for the Apollo 14 configuration and the other for J Type Mission configurations. The program consists of two mathematical models which are dynamically coupled. A model of the CSS components and lines determines the oxygen and hydrogen flowrate from each storage tank given the tank pressures and temperatures, and the electrical power subsystem and environmental control subsystem flow demands. Temperatures and pressures throughout the components and lines are also determined. A model of the CSS tankage determines the pressure and temperatures in the tanks given the flowrate from each tank and the thermal environment. The model accounts for tank stretch and includes simplified oxygen tank heater and stratification routines. The program is currently operational on the Univac 1108 computer
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