Direct comparison of sterile neutrino constraints from cosmological data, $$\nu _{e}$$ disappearance data and $$\nu _{\mu } \rightarrow \nu _{e} $$ appearance data in a $$3+1$$ model

We present a quantitative, direct comparison of constraints on sterile neutrinos derived from neutrino oscillation experiments and from Planck data, interpreted assuming standard cosmological evolution. We extend a $$1+1$$1+1 model, which is used to compare exclusion contours at the 95% Cl derived from Planck data to those from $$\nu _{e}$$νe-disappearance measurements, to a $$3+1$$3+1 model. This allows us to compare the Planck constraints with those obtained through $$\nu _{\mu }\rightarrow \nu _{e}$$νμ→νe appearance searches, which are sensitive to more than one active-sterile mixing angle. We find that the cosmological data fully exclude the allowed regions published by the LSND, MiniBooNE and Neutrino-4 collaborations, and those from the gallium and rector anomalies, at the 95% Cl. Compared to the exclusion region from the Daya Bay $$\nu _{e}$$νe-disappearance search, the Planck data are more strongly excluding above $$|\Delta m^{2}_{41}|\approx 0.1\,\mathrm {eV}^{2}$$|Δm412|≈0.1eV2 and $$m_\mathrm {eff}^\mathrm {sterile}\approx 0.2\,\mathrm {eV}$$meffsterile≈0.2eV, with the Daya Bay exclusion being stronger below these values. Compared to the combined Daya Bay/Bugey/MINOS exclusion region on $$\nu _{\mu }\rightarrow \nu _{e}$$νμ→νe appearance, the Planck data is more strongly excluding above $$\Delta m^{2}_{41}\approx 5\times 10^{-2}\,\mathrm {eV}^{2}$$Δm412≈5×10-2eV2, with the exclusion strengths of the Planck data and the Daya Bay/Bugey/MINOS combination becoming comparable below this value.

First results on precision constraints on Z - Z′ mixing with ATLAS and CMS diboson production data at the LHC at 13 TeV and predictions for Run II

The study of electroweak boson pair production provides a powerful tool to search for new phenomena beyond the Standard Model (SM). Extra neutral vector bosons Z′ decaying to charged gauge vector boson pairs W+W- are predicted in many scenarios of new physics, including models with an extended gauge sector. The diboson production allows to place stringent constraints on the Z-Z′ mixing parameter ξ and Z′ mass, MZ′. We present the Z′ exclusion region in the ξ - MZ′ plane for the first time by using data comprised of pp collisions at √s = 13 TeV and recorded by the ATLAS and CMS detectors at the CERN LHC, with integrated luminosities of 36.1 and 35.9 fb-1, respectively. The exclusion region has been significantly extended compared to that obtained from the previous analysis performed with Tevatron data, as well as with LHC data collected at 7 and 8 TeV. Also, we found that these constraints on the Z-Z′ mixing factor are more severe than those derived from the global analysis of electroweak data. Further improvement on the constraining of this mixing can be achieved from the analysis of data to be collected at higher luminosity expected in Run II.

A two-fluid model describing the finite-collisionality, stationary Alfvén wave in anisotropic plasma

The stationary inertial Alfvén (StIA) wave (Knudsen, 1996) was predicted for cold, collisionless plasma. The model was generalized (Finnegan et al., 2008) to include nonzero values of electron and ion collisional resistivity and thermal pressure. Here, the two-fluid model is further generalized to include anisotropic thermal pressure. A bounded range of values of parallel electron drift velocity is found that excludes periodic stationary Alfvén wave solutions. This exclusion region depends on the value of the local Alfvén speed VA, plasma beta perpendicular to the magnetic field β⊥ and electron temperature anisotropy.

Recent Issues in Risk-Informed Inservice Inspection of Piping

Issues related to RI-ISI that have arisen recently include: augmented ISI programs and the synergistic effects when multiple degradation mechanisms exist in a segment; start of the RI-ISI program and details of merging the RI-ISI program with the existing ASME XI program when the RI-ISI program does not start at the beginning of an interval; updates to RI-ISI programs and living program criteria; criteria to be used for additional examinations when ISI reveals unacceptable flaws; application of RI-ISI methodology to inservice examination (ISI) of break exclusion region (BER) piping.