Non-perturbative studies of N=2 conformal quiver gauge theories

We study N=2 super-conformal field theories in four dimensions that correspond to mass-deformed linear quivers with n gauge groups and (bi-)fundamental matter. We describe them using Seiberg-Witten curves obtained from an M-theory construction and via the AGT correspondence. We take particular care in obtaining the detailed relation between the parameters appearing in these descriptions and the physical quantities of the quiver gauge theories. This precise map allows us to efficiently reconstruct the non-perturbative prepotential that encodes the effective IR properties of these theories. We give explicit expressions in the cases n=1,2, also in the presence of an Omega-background in the Nekrasov-Shatashvili limit. All our results are successfully checked against those of the direct microscopic evaluation of the prepotential a la Nekrasov using localization methods.Comment: 56 pages, 7 figures, PdfLaTeX. v2: a few references added, version to appear on Fortschritte der Physi

Modular and duality properties of surface operators in N=2* gauge theories

We calculate the instanton partition function of the four-dimensional N=2* SU(N) gauge theory in the presence of a generic surface operator, using equivariant localization. By analyzing the constraints that arise from S-duality, we show that the effective twisted superpotential, which governs the infrared dynamics of the two-dimensional theory on the surface operator, satisfies a modular anomaly equation. Exploiting the localization results, we solve this equation in terms of elliptic and quasi-modular forms which resum all non-perturbative corrections. We also show that our results, derived for monodromy defects in the four-dimensional theory, match the effective twisted superpotential describing the infrared properties of certain two-dimensional sigma models coupled either to pure N=2 or to N=2* gauge theories.Comment: 51 pages, v3: references added, typos fixed, footnote added, some small changes in the text, appendix B streamlined. Matches the published versio

Surface operators in 5d gauge theories and duality relations

We study half-BPS surface operators in 5d N=1 gauge theories compactified on a circle. Using localization methods and the twisted chiral ring relations of coupled 3d/5d quiver gauge theories, we calculate the twisted chiral superpotential that governs the infrared properties of these surface operators. We make a detailed analysis of the localization integrand, and by comparing with the results from the twisted chiral ring equations obtain constraints on the 3d and 5d Chern-Simons levels so that the instanton partition function does not depend on the choice of integration contour. For these values of the Chern-Simons couplings, we comment on how the distinct quiver theories that realize the same surface operator are related to each other by Aharony-Seiberg dualities.Comment: 39 pages. v2: A few sentences rephrased, references added, and typos corrected. Matches version published in JHE

GPS radio occultation sounding to support General Circulation Models

An assessment of the suitability of the horizontal and vertical resolution of GPS radio occultation measurements for climate studies is carried out. Simple physical relations are used to estimate the consistency between horizontal and vertical resolutions of radio occultation measurements as compared with those of the existing observing systems. In particular, the horizontal scale of the upper troposphere water vapour is investigated by analysing the variability of the refractivity index using the re-analysis data from NCEP/NCAR. The computation shows that the 300 km horizontal resolution of GPS radio occultation is within the useful range and captures the water vapour variations that are relevant for climatological purposes. Next, focusing the analysis on the requirements of the vertical resolution, we study the sensitivity of a radiative model to changes in the vertical resolution, assessing the impacts of these variations on the atmospheric equilibrium. For this purpose one reference profile and other five with lower vertical resolutions are used to perform the experiment. Results show that the model is sensitive to variations in the vertical sampling, suggesting that high vertical resolution measurements are necessary for an accurate observation of the atmosphere. To further assess the influence of the vertical sampling, the thermal tropopause height dependence on the number of layers considered is studied. Results indicate that the highest vertical resolution is needed for determining the radiative component of the tropopause dynamics

GPS radio occultation sounding to support General Circulation Models

An assessment of the suitability of the horizontal and vertical resolution of GPS radio occultation measurements for climate studies is carried out. Simple physical relations are used to estimate the consistency between horizontal and vertical resolutions of radio occultation measurements as compared with those of the existing observing systems. In particular, the horizontal scale of the upper troposphere water vapour is investigated by analysing the variability of the refractivity index using the re-analysis data from NCEP/NCAR. The computation shows that the 300 km horizontal resolution of GPS radio occultation is within the useful range and captures the water vapour variations that are relevant for climatological purposes. Next, focusing the analysis on the requirements of the vertical resolution, we study the sensitivity of a radiative model to changes in the vertical resolution, assessing the impacts of these variations on the atmospheric equilibrium. For this purpose one reference profile and other five with lower vertical resolutions are used to perform the experiment. Results show that the model is sensitive to variations in the vertical sampling, suggesting that high vertical resolution measurements are necessary for an accurate observation of the atmosphere. To further assess the influence of the vertical sampling, the thermal tropopause height dependence on the number of layers considered is studied. Results indicate that the highest vertical resolution is needed for determining the radiative component of the tropopause dynamics

CP--odd Correlation in the Decay of Neutral Higgs Boson into ZZZZ, W+W−W^+W^-, or ttˉt{\bar t}

We investigate the possibility of detecting CP--odd angular correlations in the various decay modes of the neutral Higgs boson including the modes of a $ZZ$ pair, a $W^+W^-$ pair, or a heavy quark pair. It is a natural way to probe the CP character of the Higgs boson once it is identified. Final state interactions (i.e. the absorptive decay amplitude) is not required in such correlations. As an illustrative example we take the fundamental source of the CP nonconservation to be in the Yukawa couplings of the Higgs boson to the heavy fermions. A similar correlation in the process $e^+e^- \to l^+ l^- H$ is also proposed. Our analysis of these correlations will be useful for experiments in future colliders such as LEP II, SSC, LHC or NLC.Comment: 16 pages, plus 8 postscript graphs not posted befor

Biatrial Recurrence of Two Independently Growing Cardiac Myxoma in a Patient with Multiple Tumor Disease

We report the case of a 56-year-old female patient with biatrial recurrence of cardiac myxoma and extensive comorbidities. In the literature, only few cases of biatrial myxoma can be found and they generally describe a single tumor reaching both atria. We found two independently growing cardiac myxomas of both atria

Modular anomaly equations and S-duality in N=2 conformal SQCD

We use localization techniques to study the non-perturbative properties of an N = 2 $$\mathcal{N}=2$$ superconformal gauge theory with gauge group SU(3) and six fundamental flavours. The instanton corrections to the prepotential, the dual periods and the period matrix are calculated in a locus of special vacua possessing a ℤ 3 symmetry. In a semiclassical expansion, we show that these observables are constrained by S-duality via a modular anomaly equation which takes the form of a recursion relation. The solutions of the recursion relation are quasi-modular functions of Γ 1 (3), which is a subgroup of the S -duality group and is also a congruence subgroup of SL(2 , ℤ )

Clustering in 18O - absolute determination of branching ratios via high-resolution particle spectroscopy

The determination of absolute branching ratios for high-energy states in light nuclei is an important and useful tool for probing the underlying nuclear structure of individual resonances: for example, in establishing the tendency of an excited state towards α -cluster structure. Difficulty arises in measuring these branching ratios due to similarities in available decay channels, such as ( 18 O, n ) and ( 18 O, 2 n ), as well as differences in geometric efficiencies due to population of bound excited levels in daughter nuclei. Methods are presented using Monte Carlo techniques to overcome these issues