Ordered bicontinuous double-diamond morphology in subsaturation nuclear matter

We propose to identify the new "intermediate" morphology in subsaturation nuclear matter observed in a recent quantum molecular dynamics simulation with the ordered bicontinuous double-diamond structure known in block copolymers. We estimate its energy density by incorporating the normalized area-volume relation given in a literature into the nuclear liquid drop model. The resulting energy density is higher than the other five known morphologies.Comment: 4 pages, 4 figures, published in Phys. Rev.

A Derivation of the Fermi Function in Perturbative Quantum Field Theory

We postulate that the Fermi function should be derived from the amplitude, not from the solution of the Dirac equation, in the quantum field theory. Then, we obtain the following results. 1, We give the amplitude and the width of the neutron beta decay, $n \to p + e^- + \bar \nu_e$ to one loop order. It is carried out by the Feynman parameter integration. 2, As the result, we find the terms which can be interpreted as the Fermi function expanded to order $\alpha$. 3, We also give the same result using complex analysis. 4, We check that there are no such terms in the similar process, $\bar \nu_e + p \to e^+ + n$. 5, We perform the Fermi function expanded to order $\alpha^2$ using complex analysis.Comment: 8 page

Integrating out Holographic QCD back to Hidden Local Symmetry

We develop a previously proposed gauge-invariant method to integrate out infinite towers of vector and axialvector mesons arising as Kaluza-Klein (KK) modes in a class of holographic models of QCD (HQCD). We demonstrate that HQCD can be reduced to the chiral perturbation theory (ChPT) with the hidden local symmetry (HLS) (so-called HLS-ChPT) having only the lowest KK mode identified as the HLS gauge boson, and the Nambu-Goldstone bosons. The ${\cal O} (p^4)$ terms in the HLS-ChPT are completely determined by integrating out infinite towers of vector/axialvector mesons in HQCD: Effects of higher KK modes are fully included in the coefficients. As an example, we apply our method to the Sakai-Sugimoto model.Comment: To appear in proceedings of SCGT09, Nagoya, Japan, 8 page

Modeling with structure of resins in electonic compornents

In recent years, interfacial fracture becomes one of the most important problems in the assessment of reliability of electronics packaging. Especially, underfill resin is used with solder joints in flip chip packaging for preventing the thermal fatigue fracture in solder joints. In general, the interfacial strength has been evaluated on the basis of interfacial fracture mechanics concept. However, as the size of devices decrease, it is difficult to evaluate the interfacial strength quantitatively. Most of researches in the interfacial fracture were conducted on the basis of the assumption of the perfectly bonding condition though the interface has the micro-scale structure and the bonding is often imperfect. In this study, the mechanical model of the interfacial structure of resin in electronic components was proposed. Bimaterial model with the imperfect bonding condition was examined by using a finite element analysis (FEA). Stress field in the vicinity of interface depends on the interfacial structure with the imperfect bonding. In the front of interfacial crack tip, the behavior of process zone is affected by interfacial structure. However, the instability of fracture for macroscopic crack which means the fracture toughness is governed by the stress intensity factor based on the fracture mechanics concept.Comment: Submitted on behalf of TIMA Editions (http://irevues.inist.fr/tima-editions

Holographic QCD Integrated back to Hidden Local Symmetry

We develop a previously proposed gauge-invariant method to integrate out infinite tower of Kaluza-Klein (KK) modes of vector and axialvector mesons in a class of models of holographic QCD (HQCD). The HQCD is reduced by our method to the chiral perturbation theory with the hidden local symmetry (HLS) having only the lowest KK mode identified as the HLS gauge boson. We take the Sakai-Sugimoto model as a concrete HQCD, and completely determine the ${\cal O} (p^4)$ terms as well as the ${\cal O}(p^2)$ terms from the DBI part and the anomaly-related (intrinsic parity odd) gauge-invariant terms from the CS part. Effects of higher KK modes are fully included in these terms. To demonstrate power of our method, we compute momentum-dependences of several form factors such as the pion electromagnetic form factors, the $\pi^0$-$\gamma$ and $\omega$-$\pi^0$ transition form factors compared with experiment, which was not achieved before due to complication to handle infinite sums. We also study other anomaly-related quantities like $\gamma^*$-$\pi^0$-$\pi^+$-$\pi^-$ and $\omega$-$\pi^0$-$\pi^+$-$\pi^-$ vertex functions.Comment: 4 eps figures, 37 pages, latex, typos fixed; some discussions and references added; fig.4 replace

Does the three site Higgsless model survive the electroweak precision tests at loop?

We complete the list of one loop renormalization group equations and matching conditions relevant for the computation of the electroweak precision parameters $S$ and $T$ in the three site Higgsless model. We obtain one-loop formulas for $S$ and $T$ expressed in terms of physical observables such as the KK gauge boson mass $M_{W'}$, the KK fermion mass $M$, and the KK gauge boson ($W'$) couplings with light quarks and leptons $g_{W'ff}$. It is shown that these physical observables, $M_{W'}$, $M$ and $g_{W'ff}$ are severely constrained by the electroweak precision data. Unlike the tree level analysis on the ideally delocalized fermion, we find that perfect fermiophobity of $W'$ is ruled out by the precision data. We also study the cutoff dependence of our analysis. Although the model is non-renormalizable, the dependence on the cutoff parameter $\Lambda$ is shown to be non-significant.Comment: 13pages, 5figures, minor corrections made, references adde