Engine inlet distortion in a 9.2 percent scale vectored thrust STOVL model in ground effect

Advanced Short Takeoff/Vertical Landing (STOVL) aircraft which can operate from remote locations, damaged runways, and small air capable ships are being pursued for deployment around the turn of the century. To achieve this goal, NASA Lewis Research Center, McDonnell Douglas Aircraft, and DARPA defined a cooperative program for testing in the NASA Lewis 9- by 15-foot low speed wind tunnel (LSWT) to establish a database for hot gas ingestion, one of the technologies critical to STOVL. Results are presented which show the engine inlet distortions (both temperature and pressure) in a 9.2 percent scale vectored thrust STOVL model in ground effects. Results are shown for the forward nozzle splay angles of 0 degrees, -6 degrees, and 18 degrees. The model support system had 4 degrees of freedom, heated high pressure air for nozzle flow, and a suction system exhaust for inlet flow. The headwind (freestream) velocity was varied from 8 to 23 knots

Canonical curves and Kropina metrics in Lagrangian contact geometry

We present a Fefferman-type construction from Lagrangian contact to conformal structures and examine several related topics. In particular, we concentrate on describing the canonical curves and their correspondence. We show that chains and null-chains of an integrable Lagrangian contact structure are the projections of null-geodesics of the Fefferman space. Employing the Fermat principle, we realize chains as geodesics of Kropina (pseudo-Finsler) metrics. Using recent rigidity results, we show that ``sufficiently many'' chains determine the Lagrangian contact structure. Separately, we comment on Lagrangian contact structures induced by projective structures and the special case of dimension three.Comment: 25 pages, no figure

Applicability of ERTS-1 to lineament and photogeologic mapping in Montana: Preliminary report

A lineament map prepared from a mosaic of western Montana shows about 85 lines not represented on the state geologic map, including elements of a northeast-trending set through central western Montana which merit ground truth checking and consideration in regional structural analysis. Experimental fold annotation resulted in a significant local correction to the state geologic map. Photogeologic mapping studies produced only limited success in identification of rock types, but they did result in the precise delineation of a late Cretaceous or early Tertiary volcanic field (Adel Mountain field) and the mapping of a connection between two granitic bodies shown on the state map. Imagery was used successfully to map clay pans associated with bentonite beds in gently dipping Bearpaw Shale. It is already apparent that ERTS imagery should be used to facilitate preparation of a much needed statewide tectonic map and that satellite imagery mapping, aided by ground calibration, provides and economical means to discover and correct errors in the state geologic map

Measurement of the semileptonic branching fraction of the B_s meson

We report a measurement of the inclusive semileptonic branching fraction of the B_s meson using data collected with the BABAR detector in the center-of-mass energy region above the Υ(4S) resonance. We use the inclusive yield of ϕ mesons and the ϕ yield in association with a high-momentum lepton to perform a simultaneous measurement of the semileptonic branching fraction and the production rate of B_s mesons relative to all B mesons as a function of center-of-mass energy. The inclusive semileptonic branching fraction of the B_s meson is determined to be B(B_s→ℓνX)=9.5_(-2.0)^(+2.5)(stat)_(-1.9)^(+1.1)(syst)%, where ℓ indicates the average of e and μ

B^0 meson decays to ρ^0K^(*0), f_0K^(*0), and ρ^-K^(*+), including higher K^* resonances

We present branching fraction measurements for the decays B^0→ρ^0K^(*0), B^0→f_0K^(*0), and B^0→ρ^-K^(*+), where K^* is an S-wave (Kπ)_0^* or a K^*(892) meson; we also measure B^0→f_0K_2^*(1430)^0. For the K^*(892) channels, we report measurements of longitudinal polarization fractions (for ρ final states) and direct CP violation asymmetries. These results are obtained from a sample of (471.0±2.8)×10^6 BB̅ pairs collected with the BABAR detector at the PEP-II asymmetric-energy e^+e^- collider at the SLAC National Accelerator Laboratory. We observe ρ^0K^*(892)^0, ρ^0(Kπ)_0^(*0), f_0K^*(892)^0, and ρ^-K^*(892)^+ with greater than 5σ significance, including systematics. We report first evidence for f_0(Kπ)_0^(*0) and f_0K_2^*(1430)^0, and place an upper limit on ρ^-(Kπ)_0^(*+). Our results in the K^*(892) channels are consistent with no direct CP violation

Observation of the baryonic B decay B̅^0→Λ_c^+Λ̅ K^-

We report the observation of the baryonic B decay B̅ ^0→Λ_c^+Λ̅ K^- with a significance larger than 7 standard deviations based on 471×10^6 BB̅ pairs collected with the BABAR detector at the PEP-II storage ring at SLAC. We measure the branching fraction for the decay B̅ ^0→Λ_c^+Λ̅ K^- to be (3.8±0.8_(stat)±0.2_(sys)±1.0_(Λc)^+)×10^(-5). The uncertainties are statistical, systematic, and due to the uncertainty in the Λc+ branching fraction. We find that the Λ_c^+K^- invariant-mass distribution shows an enhancement above 3.5  GeV/c^2

Search for CP violation in the decay τ-→π-K_S^0(≥0π^0)ν_τ

We report a search for CP violation in the decay τ-→π-KS^0(≥0π^0)ντ using a data set of 437×10^6 τ-lepton pairs, corresponding to an integrated luminosity of 476  fb^(-1), collected with the BABAR detector at the PEP-II asymmetric-energy e^+e^- storage rings. The CP-violating decay-rate asymmetry is determined to be (-0.36±0.23±0.11)% approximately 2.8 standard deviations from the standard model prediction of (0.36±0.01)%

Study of radiative bottomonium transitions using converted photons

We use (111±1) million Υ(3S) and (89±1) million Υ(2S) events recorded by the BABAR detector at the PEP-II B-factory at SLAC to perform a study of radiative transitions between bottomonium states using photons that have been converted to e^+e^- pairs by the detector material. We observe Υ(3S)→γ_(χb0,2)(1P) decay, make precise measurements of the branching fractions for χ_(b1,2)(1P,2P)→γΥ(1S) and χ_(b1,2)(2P)→γΥ(2S) decays, and search for radiative decay to the η_b(1S) and η_b(2S) states

Search for the decay D^0 → γγ and measurement of the branching fraction for D^0 → π^0π^0

We search for the rare decay of the D^0 meson to two photons, D^0→γγ, and present a measurement of the branching fraction for a D^0 meson decaying to two neutral pions, B(D^0→π^0π^0). The data sample analyzed corresponds to an integrated luminosity of 470.5  fb^(-1) collected by the BABAR detector at the PEP-II asymmetric-energy e^+e^- collider at SLAC. We place an upper limit on the branching fraction, B(D^0→γγ)<2.2×10^(-6), at 90% confidence level. This limit improves on the existing limit by an order of magnitude. We also find B(D^0→π^0π^0)=(8.4±0.1±0.4±0.3)×10^(-4)