11,358 research outputs found
Optimized effective potential method with exact exchange and static RPA correlation
We present a new density-functional method of the self-consistent
electronic-structure calculation which does not exploit any local density
approximations (LDA). We use the exchange-correlation energy which consists of
the exact exchange and the correlation energies in the random-phase
approximation. The functional derivative of the correlation energy with respect
to the density is obtained within a static approximation. For transition
metals, it is shown that the correlation potential gives rise to a large
contribution which has the opposite sign to the exchange potential. Resulting
eigenvalue dispersions and the magnetic moments are very close to those of
LDA's and the experiments.Comment: 12pages. 4 figure
Analytical Studies on the Structure and Emission of the SS433 Jets
We study the structure and emission of the SS 433 jets in the X-ray emitting
region and in the inner and hotter portion inside the X-ray emitting region. In
order to consider the jet structure from the inner to outer regions we develop
the hybrid model combining the conical beam and the model beam whose cross
section grows with the distance more slowly. We find that the jet beams in the
inner and hotter portion are of two-temperature and emit a large amount of high
energy gamma photons. Our analyses suggest the thick absorbing envelope to
exist in the SS 433 system. Based on our results, we discuss the possible
acceleration mechanism for the SS 433 jets.Comment: 15 pages. Accepted for publication by Publ. Astron. Soc. Japa
A Lower Bound for the LS Category of a Formal Elliptic Space
We give a lower bound for the LS category of a formal elliptic space in terms of its rational cohomology.</p
Model-mapped random phase approximation to evaluate superconductivity in the fluctuation exchange approximation from first principles
We have applied the model-mapped RPA [H. Sakakibara et al., J. Phys. Soc.
Jpn. 86, 044714 (2017)] to the cuprate superconductors La2CuO4 and HgBa2CuO4,
resulting two-orbital Hubbard models. All the model parameters are determined
based on first-principles calculations. For the model Hamiltonians, we perform
fluctuation exchange calculation. Results explain relative height of Tc
observed in experiment for La2CuO4 and HgBa2CuO4. In addition, we give some
analyses for the interaction terms in the model, especially comparisons with
those of the constrained RPA.Comment: 7 pages, 4 figure
Kinesiological study of the push-up motion in spinal cord injury patients: involving measurement of hand pressure applied to a force plate.
We studied the pressure exerted by hands during push-ups in 21 paraplegic and 2 tetraplegic patients employing 4 different hand positions. In the fingers-spread position, the initial force exerted was a vertical force (Fz), followed by a medio-lateral force (Fy) and then an antero-posterior force (Fx). In the other 3 positions, the order of force type exertion was Fz, Fx, and then Fy. All subjects with neurological injury levels above T4 and subjects between T5 and T10 without spinal instrumentation could not push themselves up in the fingers-spread position. The fact that Fy is initiated before Fx in the fingers-spread position indicates that lateral balancing of the trunk is critical in this position, thus explaining why subjects without spinal instrumentation with neurological injury at a level higher than T10 could not control their spinal columns while performing push-ups. In contrast, antero-posterior balancing takes priority in the other hand positions. We believe that spinal instrumentation helps balance the trunk in the lateral direction, converting the thoracic spine into a rigid body in subjects with neurological injury at levels above T10.
</p
- …