Weak ferromagnetism with the Kondo screening effect in the Kondo lattice systems

We carefully consider the interplay between ferromagnetism and the Kondo screening effect in the conventional Kondo lattice systems at finite temperatures. Within an effective mean-field theory for small conduction electron densities, a complete phase diagram has been determined. In the ferromagnetic ordered phase, there is a characteristic temperature scale to indicate the presence of the Kondo screening effect. We further find two distinct ferromagnetic long-range ordered phases coexisting with the Kondo screening effect: spin fully polarized and partially polarized states. A continuous phase transition exists to separate the partially polarized ferromagnetic ordered phase from the paramagnetic heavy Fermi liquid phase. These results may be used to explain the weak ferromagnetism observed recently in the Kondo lattice materials.Comment: 6 pages, 6 figures; published versio

Solar system constraints on asymptotically flat IR modified Horava gravity through light deflection

In this paper, we study the motion of photons around a Kehagias-Sfetsos (KS) black hole and obtain constraints on IR modified Ho$\check{r}$ava gravity without cosmological constant ($\sim \Lambda_{W}$). An analytic formula for the light deflection angle is obtained. For a propagating photon, the deflection angle $\delta \phi$ increases with large values of the Ho$\check{r}$ava gravity parameter $\omega$. Under the UV limit $\omega \longrightarrow \infty$, deflection angle reduces to the result of usual Schwarzschild case, $4GM/R$. It is also found that with increasing scale of astronomical observation system the Ho$\check{r}$ava-Lifshitz gravity should satisfy $|\omega M^2|>1.1725 \times10^{-16}$ with 12% precision for Earth system, $|\omega M^2| > 8.27649 \times 10^{-17}$ with 17% precision for Jupiter system and $|\omega M^2| > 8.27650\times 10^{-15}$ with 0.17% precision for solar system.Comment: 13 pages, 2 figures; References added; To appear in Gen. Rel. Gra

Bs1∗B∗KB^{\ast}_{s1}B^{\ast}K form factor from QCD sum rules

In this article, we calculate the form factors and the coupling constant of the $g_{B^{\ast}_{s1}B^{\ast} K}$ vertex in the framework of the three-point QCD sum rules. Three point correlation functions responsible for the vertex are evaluated by considering both $B^{\ast}$ and $K$ mesons as off-shell states. The form factors obtained are different if the $B^{\ast}$ or the $K$ meson is off-shell but give the same coupling constant.Comment: 12 pages, 6 figures. arXiv admin note: text overlap with arXiv:1009.5320 by other author

Could Zc(4025)Z_{c}(4025) be a JP=1+J^{P}=1^{+} D∗D∗ˉD^{*}\bar{D^{*}} molecular state?

We investigate whether the newly observed narrow resonance $Z_{c}(4025)$ can be described as a $D^{*}\bar{D^{*}}$ molecular state with quantum numbers $J^{P}=1^{+}$. Using QCD sum rules, we consider contributions up to dimension six in the operator product expansion and work at leading order of $\alpha_{s}$. The mass obtained for this state is (4.05\pm 0.28) \mbox{GeV}. It is concluded that $D^{*}\bar{D^{*}}$ molecular state is a possible candidate for $Z_{c}(4025)$.Comment: 7 pages, 4 figures.Published in Eur.Phys.J. C73 (2013) 2661. arXiv admin note: text overlap with arXiv:1304.185