Two-dimensional oscillating airfoil test apparatus

A two dimensional oscillating airfoil test apparatus is presented as a method of measuring unsteady aerodynamic forces on an airfoil or rotor blade section. The oscillating airfoil test rig, which is being built for use in an 11 X 11-foot transonic wind tunnel (speed range M = 0.4 - 1.4), will allow determination of unsteady loadings and detailed pressure distributions on representative airfoil sections undergoing simulated pitching and flapping motions. The design details of the motion generating system and supporting structure are presented. This apparatus is now in the construction phase

Directional Detection of Dark Matter with MIMAC

Directional detection is a promising search strategy to discover galactic Dark Matter. We present a Bayesian analysis framework dedicated to Dark Matter phenomenology using directional detection. The interest of directional detection as a powerful tool to set exclusion limits, to authentify a Dark Matter detection or to constrain the Dark Matter properties, both from particle physics and galactic halo physics, will be demonstrated. However, such results need highly accurate track reconstruction which should be reachable by the MIMAC detector using a dedicated readout combined with a likelihood analysis of recoiling nuclei.Comment: 4 pages, 2 figures, to appear in the proceedings of the TAUP 2011 conference held in Munich (5 - 9 September, 2011

Consistent two--dimensional chiral gravity

We study chiral induced gravity in the light-cone gauge and show that the theory is consistent for a particular choice of chiralities. The corresponding Kac--Moody central charge has no forbidden region of complex values. Generalized analysis of the critical exponents is given and their relation to the $SL(2,R)$ vacuum states is elucidated. All the parameters containing information about the theory can be traced back to the characteristics of the group of residual symmetry in the light--cone gauge.Comment: 38 pages, LateX, to appear in Int.J.Mod.Phys.

Absolute frequency measurement of the 190mu and 194mu gas laser transitions

Absolute frequency measurements of 190 and 194 micron gas laser transition

Large 2HDM(II) one-loop corrections in leptonic tau decays

The one-loop contributions to the branching ratios for leptonic tau decays are calculated in the CP conserving 2HDM(II). We found that these one-loop contributions, involving both neutral and charged Higgs bosons, dominate over the tree-level H^+ exchange, the latter one being totally negligible for the decay into electron. The analysis is focused on large tanbeta enhanced contributions to the considered branching ratios. We derive a simple analytical expression for the one-loop contribution which holds in this case. We show that the leptonic branching ratios of tau are complementary to the Higgsstrahlung processes for h(H) and have a large potential on constraining parameters of the model. In this work we provide upper limits on Yukawa couplings for both light h and light A scenarios and we derive new lower limit on mass of M_{H^+} as a function of tanbeta, which differs significantly from what was considered as standard constraint based on the tree-level H^{+} exchange only. Interestingly we obtain also an upper limit on M_{H^+}. For a SM-like h scenario, with heavy and degenerate additional Higgs bosons, one-loop corrections disappear.Comment: 25 pgs. Figures and their descriptions improved, references adde

Getting beta-alpha without penguins

Oscillation effects in B0 -> Ks D0 and related processes are considered to determine delta=beta-alpha+pi. We suggest that D0 decays to CP eigenstates used in concert with inclusive D0 decays provide a powerful method for determining delta cleanly i.e. without any complication from penguin processes. The CP asymmetry is expected to be <=40% for D0 decays to non-CP eigenstates and <=80% for decays to CP eigenstates. This method can lead to a fairly accurate determination of delta with O(10^8-10^9) B-mesons.Comment: 4 pages 1 figure; Version 2: minor changes; references added; Some changes in response to Referee Comment

Complex flavour couplings in supersymmetry and unexpected CP-violation in the decay B -> phi K

Complex flavour couplings (off-diagonal mass terms) in the squark sector of supersymmetric theories may drastically alter both the rate and the CP-violating asymmetry of certain B-meson decays. We consider the effects of couplings that induce b -> s transitions and lead to final state with strangeness one. We investigate the bounds that must be satisfied by the new terms and explore the possible implications on direct and mixing induced asymmetries in the charged and neutral B -> J/Psi K and B -> phi K decays.Comment: 14 pages, 3 figure

A Submillimeter HCN Laser in IRC+10216

We report the detection of a strong submillimeter wavelength HCN laser line at a frequency near 805 GHz toward the carbon star IRC+10216. This line, the J=9-8 rotational transition within the (04(0)0) vibrationally excited state, is one of a series of HCN laser lines that were first detected in the laboratory in the early days of laser spectroscopy. Since its lower energy level is 4200 K above the ground state, the laser emission must arise from the inner part of IRC+10216's circumstellar envelope. To better characterize this environment, we observed other, thermally emitting, vibrationally excited HCN lines and find that they, like the laser line, arise in a region of temperature approximately 1000 K that is located within the dust formation radius; this conclusion is supported by the linewidth of the laser. The (04(0)0), J=9-8 laser might be chemically pumped and may be the only known laser (or maser) that is excited both in the laboratory and in space by a similar mechanism.Comment: 11 pages, 3 figure