Frequency Dependence Of The Magnetoimpedance In Amorphous Cop Electrodeposited Layers

Magnetic properties and changes of impedance upon external field (MI) are studied in amorphous CoP magnetic layers obtained by galvanostatic electrodeposition over cylindrical Cu substrates. The magnetic layer thickness is controlled by deposition time and varies between 3 and 7 μm. Due to the columnar growth of Co, thicker layers have stronger perpendicular radial anisotropy. The field and frequency dependence of the impedance is measured in the kHz/MHz range. Although it is generally accepted that a radial anisotropy should be unfavorable to the MI effect, an increase of the MI ratio with the thickness of the magnetic layer, and thus with anisotropy, is observed. Results are explained in terms of a model considering the current distribution along the sample thickness with two well-defined regions having different transport and magnetic properties. © 2000 American Institute of Physics.879 II48254827Landau, L.D., Lifshitz, E.M., (1975) Electrodynamics of Continuous Media, p. 195. , Pergamon, OxfordPanina, L.V., Mohri, K., Uchiyama, T., Noda, M., (1995) IEEE Trans. Magn., 31, p. 1249Beach, R.S., Berkowitz, A.E., (1994) Appl. Phys. Lett., 64, p. 3652Rao, K.V., Humphrey, F.B., Costa-Kramër, J.L., (1994) J. Appl. Phys., 76, p. 6204Knobel, M., Sánchez, M.L., Velázquez, J., Vázquez, M., (1995) J. Phys.: Condens. Matter, 7, pp. L-115Sommer, R.L., Chien, C.L., (1995) Appl. Phys. Lett., 67, p. 3346Panina, L.V., Mohri, K., (1996) J. Magn. Magn. Mater., 157-158, p. 137Vázquez, M., Zhukov, A.P., Aragoneses, P., Arcas, J., García-Beneytez, J.M., Marin, P., Hernando, A., IEEE Trans. Magn., , in pressBeach, R.S., Smith, N., Platt, C.L., Jeffers, F., Berkowitz, A.E., (1996) Appl. Phys. Lett., 68, p. 2753Usov, N., Antonov, A., Granovsky, A., (1997) J. Magn. Magn. Mater., 171, p. 64Favieres, C., Aroca, C., Sánchez, M.C., Rao, K.V., Madurga, V., (1998) J. Magn. Magn. Mater., 177-181, p. 107Vázquez, M., Sinnecker, J.P., Kurlyandskaya, G.V., (1999) Mater. Sci. Forum, 302-303, p. 209Sinnecker, J.P., Knobel, M., Sartorelli, M.L., Schonmaker, J., Silva, F.C.S., (1998) J. Phys. IV, 8 (PR2), p. 665Machado, F.L.A., Rodrigues, A.R., Puça, A.A., De Araujo, A.E.P., (1999) Mat. Sci. Forum, 302-303, p. 202Cargil III, G.S., Gambino, R.J., Cuomo, J.J., (1974) IEEE Trans. Magn., MAG-10, p. 803Dietz, G., Bestgen, H., Hungenberg, J., (1978) J. Magn. Magn. Mater., 9, p. 208Riveiro, J.M., Sánchez-Trujillo, M.C., (1980) IEEE Trans. Magn., MAG-16, p. 1426Luborsky, F.E., (1983) Amorphous Metallic Alloys, , Butterworths, LondonMénard, D., Britel, M., Ciureanu, P., Yelon, A., (1998) J. Appl. Phys., 84, p. 2805Kraus, L., (1999) J. Magn. Magn. Mater., 195, p. 764Yelon, A., Ménard, D., Britel, M., Ciureanu, P., (1996) Appl. Phys. Lett., 69, p. 308

Energy Transfer between Throats from a 10d Perspective

Strongly warped regions, also known as throats, are a common feature of the type IIB string theory landscape. If one of the throats is heated during cosmological evolution, the energy is subsequently transferred to other throats or to massless fields in the unwarped bulk of the Calabi-Yau orientifold. This energy transfer proceeds either by Hawking radiation from the black hole horizon in the heated throat or, at later times, by the decay of throat-localized Kaluza-Klein states. In both cases, we calculate in a 10d setup the energy transfer rate (respectively decay rate) as a function of the AdS scales of the throats and of their relative distance. Compared to existing results based on 5d models, we find a significant suppression of the energy transfer rates if the size of the embedding Calabi-Yau orientifold is much larger than the AdS radii of the throats. This effect can be partially compensated by a small distance between the throats. These results are relevant, e.g., for the analysis of reheating after brane inflation. Our calculation employs the dual gauge theory picture in which each throat is described by a strongly coupled 4d gauge theory, the degrees of freedom of which are localized at a certain position in the compact space.Comment: 25 pages; a comment adde

Designing for interaction immediacy to enhance social skills of children with autism

Children with Autism Spectrum Disorder often require therapeutic interventions to support engagement in effective social interactions. In this paper, we present the results of a study conducted in three public schools that use an educational and behavioral intervention for the instruction of social skills in changing situational contexts. The results of this study led to the concept of interaction immediacy to help children maintain appropriate spatial boundaries, reply to conversation initiators, disengage appropriately at the end of an interaction, and identify potential communication partners. We describe design principles for Ubicomp technologies to support interaction immediacy and present an example design. The contribution of this work is twofold. First, we present an understanding of social skills in mobile and dynamic contexts. Second, we introduce the concept of interaction immediacy and show its effectiveness as a guiding principle for the design of Ubicomp applications

Observation of Orbitally Excited B_s Mesons

We report the first observation of two narrow resonances consistent with states of orbitally excited (L=1) B_s mesons using 1 fb^{-1} of ppbar collisions at sqrt{s} = 1.96 TeV collected with the CDF II detector at the Fermilab Tevatron. We use two-body decays into K^- and B^+ mesons reconstructed as B^+ \to J/\psi K^+, J/\psi \to \mu^+ \mu^- or B^+ \to \bar{D}^0 \pi^+, \bar{D}^0 \to K^+ \pi^-. We deduce the masses of the two states to be m(B_{s1}) = 5829.4 +- 0.7 MeV/c^2 and m(B_{s2}^*) = 5839.7 +- 0.7 MeV/c^2.Comment: Version accepted and published by Phys. Rev. Let

Anisotropy studies around the galactic centre at EeV energies with the Auger Observatory

Data from the Pierre Auger Observatory are analyzed to search for anisotropies near the direction of the Galactic Centre at EeV energies. The exposure of the surface array in this part of the sky is already significantly larger than that of the fore-runner experiments. Our results do not support previous findings of localized excesses in the AGASA and SUGAR data. We set an upper bound on a point-like flux of cosmic rays arriving from the Galactic Centre which excludes several scenarios predicting sources of EeV neutrons from Sagittarius $A$. Also the events detected simultaneously by the surface and fluorescence detectors (the `hybrid' data set), which have better pointing accuracy but are less numerous than those of the surface array alone, do not show any significant localized excess from this direction.Comment: Matches published versio

Search for a W' boson decaying to a bottom quark and a top quark in pp collisions at sqrt(s) = 7 TeV

Results are presented from a search for a W' boson using a dataset corresponding to 5.0 inverse femtobarns of integrated luminosity collected during 2011 by the CMS experiment at the LHC in pp collisions at sqrt(s)=7 TeV. The W' boson is modeled as a heavy W boson, but different scenarios for the couplings to fermions are considered, involving both left-handed and right-handed chiral projections of the fermions, as well as an arbitrary mixture of the two. The search is performed in the decay channel W' to t b, leading to a final state signature with a single lepton (e, mu), missing transverse energy, and jets, at least one of which is tagged as a b-jet. A W' boson that couples to fermions with the same coupling constant as the W, but to the right-handed rather than left-handed chiral projections, is excluded for masses below 1.85 TeV at the 95% confidence level. For the first time using LHC data, constraints on the W' gauge coupling for a set of left- and right-handed coupling combinations have been placed. These results represent a significant improvement over previously published limits.Comment: Submitted to Physics Letters B. Replaced with version publishe

Search for the standard model Higgs boson decaying into two photons in pp collisions at sqrt(s)=7 TeV

A search for a Higgs boson decaying into two photons is described. The analysis is performed using a dataset recorded by the CMS experiment at the LHC from pp collisions at a centre-of-mass energy of 7 TeV, which corresponds to an integrated luminosity of 4.8 inverse femtobarns. Limits are set on the cross section of the standard model Higgs boson decaying to two photons. The expected exclusion limit at 95% confidence level is between 1.4 and 2.4 times the standard model cross section in the mass range between 110 and 150 GeV. The analysis of the data excludes, at 95% confidence level, the standard model Higgs boson decaying into two photons in the mass range 128 to 132 GeV. The largest excess of events above the expected standard model background is observed for a Higgs boson mass hypothesis of 124 GeV with a local significance of 3.1 sigma. The global significance of observing an excess with a local significance greater than 3.1 sigma anywhere in the search range 110-150 GeV is estimated to be 1.8 sigma. More data are required to ascertain the origin of this excess.Comment: Submitted to Physics Letters

Search for direct production of charginos and neutralinos in events with three leptons and missing transverse momentum in √s = 7 TeV pp collisions with the ATLAS detector

A search for the direct production of charginos and neutralinos in final states with three electrons or muons and missing transverse momentum is presented. The analysis is based on 4.7 fb−1 of proton–proton collision data delivered by the Large Hadron Collider and recorded with the ATLAS detector. Observations are consistent with Standard Model expectations in three signal regions that are either depleted or enriched in Z-boson decays. Upper limits at 95% confidence level are set in R-parity conserving phenomenological minimal supersymmetric models and in simplified models, significantly extending previous results