44 research outputs found
Evidence for centennial scale sea level variability during the Medieval Climate Optimum (Crusader Period) in Israel, eastern Mediterranean
No full textThe current study provides evidence supporting a sea-level drop of up to about 50 ± 20 cm at the eastern coasts of the Mediterranean basin during the period AD 900–1300. The estimate is based on a variety of archaeological remains, mostly from the Crusader period, compared with other archaeological and biological proxies of sea level from the periods before and after.The Crusader low levels overlap the period known as the ‘Medieval Warm Period’ (MWP) or the ‘Medieval Climate Anomaly’ (MCA). On the basis of published data it appears that a positive North Atlantic Oscillation (NAO) phase coincided with a negative Southern Oscillation Index (SOI), the former affecting the temperature and freshwater flux in the Mediterranean Sea and most of its rivers, and the latter affecting the Nile outflow. Changes of 0.125 psu in salinity and 0.4 °C are estimated as upper limits for the change, and these are expected to cause a sea-level drop consistent in magnitude with the observed values. These provide the upper limit for a regional climate-forcing attribution of the observed sea level low. The possibility of crustal uplifts contributing to the observed changes is also discussed
Electrotelluric noise minimization for seismoelectric effect detection
No full textThree electrotelluric stations were installed in Israel in order to examine electric field changes associated with earthquake occurrence at the Bar-Giora observatory, at the Ein Gedi field school and on Mt. Tur'an. During the observation period 1994-1995, no earthquake was shown to cause any changes in the electric field at the measurement sites. This study focused on signal processing of electric field continuous measurements. The main purpose was to identify, and consequently filter out, signals caused by local and extra-terrestrial sources. New procedures for data processing were developed mainly using data from the Bar-Giora station, which has been instrumental in the experiments.JCR Journalope
Conversion of B-rep CAD models into globally G<sup>1</sup> triangular splines
No full textExisting techniques that convert B-rep (boundary representation) patches into Clough-Tocher splines guarantee watertight, that is C0, conversion results across B-rep edges. In contrast, our approach ensures global tangent-plane, that is G1, continuity of the converted B-rep CAD models. We achieve this by careful boundary curve and normal vector management, and by converting the input models into Shirman-Séquin macro-elements near their (trimmed) B-rep edges. We propose several different variants and compare them with respect to their locality, visual quality, and difference with the input B-rep CAD model. Although the same global G1 continuity can also be achieved by conversion techniques based on subdivision surfaces, our approach uses triangular splines and thus enjoys full compatibility with CAD.</p
Ultra Sensitive Geomagnetic Monitoring at Eilat Geophysical Observatory
No full textLong-term precise magnetic observations are being carried out at the Eilat test site as a part of active tectonic fault multi-sensor geophysical monitoring. The gradiometer system comprises three highly sensitive potassium total field sensors with short bases - up to 50 m. The gradiometer time series contain residuals of external magnetic field variations, which are essentially homogeneous over such short distances. Mutual regression analysis of the gradiometer and the vector magnetometer time series was proved to be an effective tool in reduction of the influence of external homogeneous variation on gradiometer readings. Monitoring results together with time dependence of regression coefficients are analyzed
Electrotelluric noise minimization for seismoelectric effect detection
No full textThree electrotelluric stations were installed in Israel in order to examine electric field changes associated with earthquake occurrence at the Bar-Giora observatory, at the Ein Gedi field school and on Mt. Tur'an. During the observation period 1994-1995, no earthquake was shown to cause any changes in the electric field at the measurement sites. This study focused on signal processing of electric field continuous measurements. The main purpose was to identify, and consequently filter out, signals caused by local and extra-terrestrial sources. New procedures for data processing were developed mainly using data from the Bar-Giora station, which has been instrumental in the experiments
On the Unexpected Stability of the Dianion of Perylene Diimide in WaterA Computational Study
No full textIt was recently reported (Shirman, J. Phys. Chem. B, 2008, 112, 8855) that the stable dianion of perylene diimide can be prepared in water. Herein, a computational study (using DFT at the M06-2X/6-31++G** level of theory) of this species is presented. It is shown that this dianion is aromatic and that its reaction with water is highly endergonic. The primary cause for this is the stabilization provided by the enhanced aromaticity of the dianion relative to its neutral counterpart. Comparison with other aromatic dianions is also presented
Search for diphoton events with large missing transverse momentum in 1 fb<sup>-1</sup> of 7 TeV proton–proton collision data with the ATLAS detector
No full textA search for diphoton events with large missing transverse momentum has been performed using 1.07 fb−1of proton–proton collision data at √s=7 TeV recorded with the ATLAS detector. No excess of events was observed above the Standard Model prediction and 95% Confidence Level (CL) upper limits are set on the production cross section for new physics. The limits depend on each model parameter space and vary as follows: σ<(22–129) fb in the context of a generalised model of gauge-mediated supersymmetry breaking (GGM) with a bino-like lightest neutralino, σ<(27–91) fb in the context of a minimal model of gauge-mediated supersymmetry breaking (SPS8), and σ< (15–27) fb in the context of a specific model with one universal extra dimension (UED). A 95% CL lower limit of 805 GeV, for bino masses above 50 GeV, is set on the GGM gluino mass. Lower limits of 145 TeV and 1.23 TeV are set on the SPS8 breaking scale ∧ and on the UED compactification scale 1/R, respectively. These limits provide the most stringent tests of these models to date
Dynamics of 3D SUSY gauge theories with antisymmetric matter
No full textWe investigate the IR dynamics of N = 2 SUSY gauge theories in 3D with antisymmetric matter. The presence of the antisymmetric fields leads to further splitting of the Coulomb branch. Counting zero modes in the instanton background suggests that more than a single direction along the Coulomb branch may remain unlifted. We examine the case of SU(4) with one or two antisymmetric fields and various flavors in detail. Using the results for the corresponding 4D theories, we find the IR dynamics of the 3D cases via compactification and a real mass deformation. We find that for the s-confining case with two antisymmetric fields, a second unlifted Coulomb branch direction indeed appears in the low-energy dynamics. We present several non-trivial consistency checks to establish the validity of these results. We also comment on the expected structure of general s-confining theories in 3D, which might involve several unlifted Coulomb branch directions. © 2014 The Author(s)
Search for supersymmetry at √s= 8 TeV in final states with jets and two same-sign leptons or three leptons with the ATLAS detector
No full textA search for strongly produced supersymmetric particles is conducted using signatures involving multiple energetic jets and either two isolated leptons (e or μ) with the same electric charge, or at least three isolated leptons. The search also utilises jets originating from b-quarks, missing transverse momentum and other observables to extend its sensitivity. The analysis uses a data sample corresponding to a total integrated luminosity of 20.3 fb-1 of √s = 8 TeV proton-proton collisions recorded with the ATLAS detector at the Large Hadron Collider in 2012. No deviation from the Standard Model expectation is observed. New or significantly improved exclusion limits are set on a wide variety of supersymmetric models in which the lightest squark can be of the first, second or third generations, and in which R-parity can be conserved or violated
Search for supersymmetry in events with large missing transverse momentum, jets, and at least one tau lepton in 7 TeV proton-proton collision data with the ATLAS detector
No full textATLAS Contributor: Paul Douglas Jackson of School of Chemistry and Physics, University of Adelaide, Adelaide, Australia. Extent: 22p.A search for supersymmetry (SUSY) in events with large missing transverse momentum, jets, and at least one hadronically decaying τ lepton, with zero or one additional light lepton (e/μ), has been performed using 4.7 fb−1 of proton-proton collision data at √s = 7 TeV recorded with the ATLAS detector at the Large Hadron Collider. No excess above the Standard Model background expectation is observed and a 95 % confidence level visible cross-section upper limit for new phenomena is set. In the framework of gauge-mediated SUSY-breaking models, lower limits on the mass scale Λ are set at 54 TeV in the regions where the ˜τ₁ is the next-to-lightest SUSY particle (tanβ > 20). These limits provide the most stringent tests to date of GMSB models in a large part of the parameter space considered.The ATLAS Collaboratio
