29,388 research outputs found
Flexible ring slosh damping baffle Patent
Flexible ring slosh damping baffle for spacecraft fuel tan
The Apollo spacecraft: A chronology volume 4, 21 January 1966 - 13 July 1974
This final volume of the chronology is divided into three parts: (1) preparation for flight, the accident, and investigation; (2) recovery, spacecraft redefinition, and the first manned flight; and (3) man circles the moon, the Eagle lands, and manned space exploration. Congressional documents, official correspondence, government and contractor reports, memoranda, working papers, and minutes of meetings were used as primary sources. A relatively few entries are based on press releases and newspaper and magazine articles
Flexible ring baffles for damping liquid slosh
Slosh damping, obtained through the use of small, less massive, flexible baffles, provides a relatively lightweight system for damping the motions of liquid propellants in launch vehicles, missiles, and other tankage systems
Phenomenology of Dirac Neutrinogenesis in Split Supersymmetry
In Split Supersymmetry scenarios the possibility of having a very heavy
gravitino opens the door to alleviate or completely solve the worrisome
"gravitino problem'' in the context of supersymmetric baryogenesis models. Here
we assume that the gravitino may indeed be heavy and that Majorana masses for
neutrinos are forbidden as well as direct Higgs Yukawa couplings between left
and right handed neutrinos. We investigate the viability of the mechansim known
as Dirac leptogenesis (or neutrinogenesis), both in solving the baryogenesis
puzzle and explaining the observed neutrino sector phenomenology. To
successfully address these issues, the scenario requires the introduction of at
least two new heavy fields. If a hierarchy among these new fields is
introduced, and some reasonable stipulations are made on the couplings that
appear in the superpotential, it becomes a generic feature to obtain the
observed large lepton mixing angles. We show that in this case, it is possible
simultaneously to obtain both the correct neutrino phenomenology and enough
baryon number, making thermal Dirac neutrinogenesis viable. However, due to
cosmological constraints, its ability to satisfy these constraints depends
nontrivially on model parameters of the overall theory, particularly the
gravitino mass. Split supersymmetry with m_{3/2} between 10^{5} and 10^{10} GeV
emerges as a "natural habitat" for thermal Dirac neutrinogenesis.Comment: 37 pages, 8 figure
Lepton Flavor Violation and Supersymmetric Dirac Leptogenesis
Dirac leptogenesis (or Dirac neutrinogenesis), in which neutrinos are purely
Dirac particles, is an interesting alternative to the standard leptogenesis
scenario. In its supersymmetric version, the modified form of the
superpotential required for successful baryogenesis contributes new,
generically non-flavor-diagonal terms to the slepton and sneutrino mass
matrices. In this work, we examine how current experimental bounds on
flavor-changing effects in the lepton sector (and particularly the bound on Mu
-> e Gamma) constrain Dirac leptogenesis and we find that it is capable of
succeeding with superpartner masses as low as 100 GeV. For such light scalars
and electroweakinos, upcoming experiments such as MEG are generically expected
to observe signals of lepton flavor violation.Comment: 15 pages, 4 figures, corrected parametric dependance on leading LFV
term, figure 2 and discussion modified accordingly, conclusions unchange
Design and experimental evaluation of a swept supercritical Laminar Flow Control (LFC) airfoil
A large chord swept supercritical laminar flow control (LFC) airfoil was designed, constructed, and tested in the NASA Langley 8-ft Transonic Pressure Tunnel (TPT). The LFC airfoil experiment was established to provide basic information concerning the design and compatibility of high-performance supercritical airfoils with suction boundary layer control achieved through discrete fine slots or porous surface concepts. It was aimed at validating prediction techniques and establishing a technology base for future transport designs and drag reduction. Good agreement was obtained between measured and theoretically designed shockless pressure distributions. Suction laminarization was maintained over an extensive supercritical zone up to high Reynolds numbers before transition gradually moved forward. Full-chord laminar flow was maintained on the upper and lower surfaces at M sub infinity = 0.82 up to R sub c is less than or equal to 12 x 10 to the 6th power. When accounting for both the suction and wake drag, the total drag could be reducted by at least one-half of that for an equivalent turbulent airfoil. Specific objectives for the LFC experiment are given
GEOS I tracking station positions on the SAO standard earth /C-5/
GEOS 1 tracking station positions on SAO standard earth C-5 mode
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