179 research outputs found
Coupled channel approach to strangeness S = -2 baryon-bayron interactions in Lattice QCD
The baryon-baryon interactions with strangeness S = -2 with the flavor SU(3)
breaking are calculated for the first time by using the HAL QCD method extended
to coupled channel system in lattice QCD. The potential matrices are extracted
from the Nambu-Bethe-Salpeter wave functions obtained by the 2+1 flavor gauge
configurations of CP-PACS/JLQCD Collaborations with a physical volume of 1.93
fm cubed and with m_pi/m_K = 0.96, 0.90, 0.86. The spatial structure and the
quark mass dependence of the potential matrix in the baryon basis and in the
SU(3) basis are investigated.Comment: 17 pages, 15 figure
Baryon-Baryon Interactions in the Flavor SU(3) Limit from Full QCD Simulations on the Lattice
We investigate baryon-baryon (BB) interactions in the 3-flavor full QCD
simulations with degenerate quark masses for all flavors. The BB potentials in
the orbital S-wave are extracted from the Nambu-Bethe-Salpeter wave functions
measured on the lattice. We observe strong flavor-spin dependences of the BB
potentials at short distances. In particular, a strong repulsive core exists in
the flavor-octet and spin-singlet channel (the 8_s representation), while an
attractive core appears in the flavor singlet channel (the 1 representation).
We discuss a relation of such flavor-spin dependence with the Pauli exclusion
principle in the quark level. Possible existence of an H-dibaryon resonance
above the Lambda-Lambda threshold is also discussed.Comment: 16 pages, 4 figures, ptptex.cls use
interaction from 2+1 flavor lattice QCD
We investigate the interaction between baryons in the
channel from 2+1 flavor lattice QCD simulations. On the basis of the HAL QCD
method, the potential is extracted from the Nambu-Bethe-Salpeter
wave function calculated on the lattice by using the PACS-CS gauge
configurations with the lattice spacing fm, the lattice volume
fm and the quark masses corresponding to MeV
and MeV. The potential has a repulsive
core at short distance and an attractive well at intermediate distance.
Accordingly, the phase shift obtained from the potential shows moderate
attraction at low energies. Our data indicate that the system
with the present quark masses may appear close to the unitary limit where the
scattering length diverges.Comment: 9 pages, 4 figures, 1 tabl
Medium-heavy nuclei from nucleon-nucleon interactions in lattice QCD
On the basis of the Brueckner-Hartree-Fock method with the nucleon-nucleon
forces obtained from lattice QCD simulations, the properties of the
medium-heavy doubly-magic nuclei such as 16^O and 40^Ca are investigated. We
found that those nuclei are bound for the pseudo-scalar meson mass M_PS ~ 470
MeV. The mass number dependence of the binding energies, single-particle
spectra and density distributions are qualitatively consistent with those
expected from empirical data at the physical point, although these hypothetical
nuclei at heavy quark mass have smaller binding energies than the real nuclei.Comment: 5 pages, 5 figures, published in Physical Review C as a Rapid
Communicatio
Identification of human Kir2.2 (KCNJ12) gene encoding functional inward rectifier potassium channel in both mammalian cells and Xenopus oocytes
AbstractArginine residue at position 285 (R285) in the intracellular C-terminal domain of inward rectifier potassium channel Kir2.2 is conserved in many species, but missing in previously reported human Kir2.2 sequences. We here identified the human Kir2.2 gene in normal individuals, which contained R285 in the deduced amino-acid sequence (hKir2.2/R285). All 30 individuals we examined were homozygous for Kir2.2/R285 gene. The hKir2.2/R285 was electrophysiologically functional in both mammalian cells and Xenopus oocytes. However, the hKir2.2 missing R285 was functional only in Xenopus oocytes, but not in mammalian cells. Thus, R285 in Kir2.2 is important for its functional expression in mammalian cells
Towards Lattice QCD Baryon Forces at the Physical Point: First Results
Lattice QCD calculations of baryon forces are performed for the first time
with (almost) physical quark masses. dynamical clover fermion gauge
configurations are generated at the lattice spacing of fm on a
lattice with quark masses corresponding to
MeV. Baryon forces are calculated using the
time-dependent HAL QCD method. In this report, we study and
systems both in and - channels, and the results for the
central and tensor forces as well as phase shifts in the
channel are presented.Comment: Talk given at the 12th International Conference on Hypernuclear and
Strange Particle Physics (HYP2015), Sendai, Japan, 7-12 Sep 2015, 4 pages, 6
figure
- …