44,129 research outputs found
Ion engine thrust vector study Quarterly report
Thrust stand and thruster designs for ion engine
Triple mode Cepheid masses
Unconventional composition structures are proposed to explain the periods of the triple mode Cepheid aC And. A strong Cepheid wind appears to enrich helium in the convection zones down to about 60,000 K or 70,000 K. Then some downward partial mixing occurs to the bottom of a layer with about 1-q = .0005 of the stellar mass. It was found that AC And was not unlike anomalous Cepheids. However, masses of betwen one and two solar masses are suggested and the population is more likely a type two
Marshall information retrieval and display system (MIRADS)
Program for data management system allows sophisticated inquiries while utilizing simplified language. Online system is composed of several programs. System is written primarily in COBOL with routines in ASSEMBLER and FORTRAN V
A study of solid-propellant vaporization and diffusion processes Final technical report
Vaporization rate and diffusion coefficient determined for organic additives to polyurethane solid propellants - dioctyl adipate and ferrocen
Isolation and analysis of ribonucleic acids
Ribonucleic acids are concentrated in certain parts of the cell. Separation of these parts usually precedes isolation of the ribonucleic acids they contain. This separation is accomplished by a process of cell fractionation (Mathias, 1966)
The Semiclassical Limit for and Gauge Theory on the Torus
We prove that for and quantum gauge theory on a torus,
holonomy expectation values with respect to the Yang-Mills measure d\mu_T(\o)
=N_T^{-1}e^{-S_{YM}(\o)/T}[{\cal D}\o] converge, as , to
integrals with respect to a symplectic volume measure on the moduli
space of flat connections on the bundle. These moduli spaces and the symplectic
structures are described explicitly.Comment: 18 page
Constraining Mass Spectra with Sterile Neutrinos from Neutrinoless Double Beta Decay, Tritium Beta Decay and Cosmology
We analyze the constraints on neutrino mass spectra with extra sterile
neutrinos as implied by the LSND experiment. The various mass related
observables in neutrinoless double beta decay, tritium beta decay and cosmology
are discussed. Both neutrino oscillation results as well as recent cosmological
neutrino mass bounds are taken into account. We find that some of the allowed
mass patterns are severely restricted by the current constraints, in particular
by the cosmological constraints on the total sum of neutrino masses and by the
non-maximality of the solar neutrino mixing angle. Furthermore, we estimate the
form of the four neutrino mass matrices and also comment on the situation in
scenarios with two additional sterile neutrinos.Comment: 40 pages, 9 figures. Minor changes, matches version in PR
The Effects of Massive Substructures on Image Multiplicities in Gravitati onal Lenses
Surveys for gravitational lens systems have typically found a significantly
larger fraction of lenses with four (or more) images than are predicted by
standard ellipsoidal lens models (50% versus 25-30%). We show that including
the effects of smaller satellite galaxies, with an abundance normalized by the
observations, significantly increases the expected number of systems with more
than two images and largely explains the discrepancy. The effect is dominated
by satellites with ~20% the luminosity of the primary lens, in rough agreement
with the typical luminosities of the observed satellites. We find that the lens
systems with satellites cannot, however, be dropped from estimates of the
cosmological model based on gravitational lens statistics without significantly
biasing the results.Comment: 23 pages, 7 figures, more discussion of sis vs sie and inclusion of
uncorrelated contribution
Multiplicativity of maximal output purities of Gaussian channels under Gaussian inputs
We address the question of the multiplicativity of the maximal p-norm output
purities of bosonic Gaussian channels under Gaussian inputs. We focus on
general Gaussian channels resulting from the reduction of unitary dynamics in
larger Hilbert spaces. It is shown that the maximal output purity of tensor
products of single-mode channels under Gaussian inputs is multiplicative for
any p>1 for products of arbitrary identical channels as well as for a large
class of products of different channels. In the case of p=2 multiplicativity is
shown to be true for arbitrary products of generic channels acting on any
number of modes.Comment: 9 page
Low-speed inducers for cryogenic upper-stage engines
Two-phase, low-speed hydrogen and oxygen inducers driven by electric motors and applicable to the tug engine were designed and constructed. The oxygen inducer was tested in liquid and two-phase oxygen. Its head and flow performance were approximately as designed, and it was able to accelerate to full speed in 3 seconds and produce its design flow and head. The analysis of the two-phase data indicated that the inducer was able to pump with vapor volume fractions in excess of 60 percent. The pump met all of its requirements (duration of runs and number of starts) to demonstrate its mechanical integrity
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