Penta-quark baryon from the QCD Sum Rule

Exotic penta-quark baryon with strangeness +1, \Theta^+, is studied in the QCD sum rule approach. We derive sum rules for the positive and negative parity baryon states with J=1/2 and I=0. It is found that the standard values of the QCD condensates predict a negative parity \Theta^+ of mass \simeq 1.5 GeV, while no positive parity state is found. We stress the roles of chiral-odd condensates in determining the parity and mass of \Theta^+.Comment: 7 pages, 3 figures, To be published in Phys.Lett.

Trajectories of distress following the great East Japan earthquake : a multi-wave prospective study

The March 2011 Great East Japan Earthquake, tsunami, and nuclear leak were complex traumas. We examined psychological distress in the years following the earthquake using growth mixture modeling to classify responses from 2,599 linked respondents (2012–2016). We identified four classes of trajectories following the disaster: resilient (76% of respondents), delayed distress (8%), recovery (8%), and chronic distress (7%). Compared with the resilient class, other class members were less likely to be female and had less social support. Survivors in the recovery group were more likely to live in prefabricated housing. Although distress has decreased over time, specific populations continue to require targeted intervention

Magnetic order and frustrated dynamics in Li(Ni0.8Co0.1Mn0.1)O2: a study by {\mu}+SR and SQUID magnetometry

Recently, the mixed transition metal oxides of the form Li(Ni1-y-zCoyMnz)O2, have become the center of attention as promising candidates for novel battery material. These materials have also revealed very interesting magnetic properties due to the alternate stacking of planes of metal oxides on a 2D triangular lattice and the Li-layers. The title compound, Li(Ni0.8Co0.1Mn0.1)O2, has been investigated by both magnetometry and measurements and {\mu}+SR. We find the evolution of localized magnetic moments with decreasing temperature below 70 K. The magnetic ground state (T = 2 K) is, however, shown to be a frustrated system in 3D, followed by a transition into a possible 2D spinglass above 22 K. With further increasing temperature the compound show the presence of remaining correlations with increasing effective dimensionality all the way up to the ferrimagnetic transition at TC = 70 K.Comment: Accepted for publication in Physics Procedia (muSR2011 Conference

Magnetic order and transitions in the spin-web compound Cu3TeO6

The spin-web compound Cu3TeO6, belongs to an intriguing group of materials where magnetism is governed by 3d9 copper Cu2+ ions. This compound has been sparsely experimentally studied and we here present the first investigation of its local magnetic properties using muon-spin relaxation/rotation ({\mu}+SR). Our results show a clear long-range 3D magnetic order below TN as indicated by clear zero-field (ZF) muon-precessions. At TN = 61.7 K a very sharp transition is observed in the weak transverse-field (wTF) as well as ZF data. Contrary to suggestions by susceptibility measurements and inelastic neutron scattering, we find no evidence for either static or dynamic (on the time-scale of {\mu}+SR) spin-correlations above TN

Na-ion dynamics in Quasi-1D compound NaV2O4

We have used the pulsed muon source at ISIS to study high-temperature Na-ion dynamics in the quasi-one-dimensional (Q1D) metallic antiferromagnet NaV2O4. By performing systematic zero-field and longitudinal-field measurements as a function of temperature we clearly distinguish that the hopping rate increases exponentially above Tdiff=250 K. The data is well fitted to an Arrhenius type equation typical for a diffusion process, showing that the Na-ions starts to be mobile above Tdiff . Such results makes this compound very interesting for the tuning of Q1D magnetism using atomic-scale ion-texturing through the periodic potential from ordered Na-vacancies. Further, it also opens the door to possible use of NaV2O4 and related compounds in energy related applications.Comment: Accepted for publication in Journal of Physics: Conference Series (2014