We investigate baryon-baryon
(BB)
interactions in the strangeness S = −2 sector via the coupled-channel HAL QCD method which enables us to extract the scattering observables from Nambu-Bethe-Salpeter ...(NBS) wave function on the lattice. The simulations are performed with (almost) physical quark masses (m
π
= 146MeV) and a huge lattice volume of
La
= 8.1fm. We discuss the fate of H-dibaryon state through the ΛΛ and NΞ coupled-channel scatterings
Quark mass dependence of the equation of state (EOS) for nucleonic matter is investigated, on the basis of the Brueckner-Hartree-Fock method with the nucleon-nucleon interaction extracted from ...lattice QCD simulations. We observe saturation of nuclear matter at the lightest available quark mass corresponding to the pseudoscalar meson mass ≃469 MeV. Mass-radius relation of the neutron stars is also studied with the EOS for neutron-star matter from the same nuclear force in lattice QCD. We observe that the EOS becomes stiffer and thus the maximum mass of neutron star increases as the quark mass decreases toward the physical point.
The sanity check is to rule out certain classes of obviously false results, not to catch every possible error. After reviewing such a sanity check for
NN
bound states with the Lüscher’s finite volume ...formula 1–3, we give further evidences for the operator dependence of plateaux, a symptom of the fake plateau problem, against the claim 4. We then present our critical comments on 5 by NPLQCD: (i) Operator dependences of plateaux in NPL2013 6, 7 exist with the P value of 4–5%. (ii) The volume independence of plateaux in NPL2013 does not prove their correctness. (iii) Effective range expansions (EREs) in NPL2013 violate the physical pole condition. (iv) Their comment is partly based on new data and analysis different from the original ones. (v) Their new ERE does not satisfy the Lüscher’s finite volume formula.
We present the latest lattice QCD results for baryon interactions obtained at nearly physical quark masses. N
f
= 2 + 1 nonperturbatively
O(a)
-improved Wilson quark action with stout smearing and ...Iwasaki gauge action are employed on the lattice of (96a)
4
≃(8.1fm)
4
with a
-1
≃2.3 GeV, where m
π
≃146 MeV and m
K
≃525 MeV. In this report, we study the two-nucleon systems and two-Ξ systems in
1
S
0
channel and
3
S
1
-
3
D
1
coupled channel, and extract central and tensor interactions by the HAL QCD method. We also present the results for the NΩ interaction in
5
S
2
channel which is relevant to the NΩ pair-momentum correlation in heavy-ion collision experiments.
We propose a new method to extract hadron interactions above inelastic threshold from the Nambu–Bethe–Salpeter amplitude in lattice QCD. We consider the scattering such as A + B → C + D, where A, B, ...C, D are names of different 1-particle states. An extension to cases where particle productions occur during scatterings is also discussed. (Communicated by Toshimitsu YAMAZAKI, M.J.A.)
We present our recent results of baryon interactions with strangeness S = −1 based on Nambu-Bethe-Salpeter (NBS) correlation functions calculated fromlattice QCD with almost physical quark masses ...corresponding to (
m
k
,m
k
) ≈ (146, 525) MeV and large volume (
La
)
4
≈ (
96a
)
4
≈ (8.1 fm)
4
. In order to perform a comprehensive study of baryon interactions, a large number of NBS correlation functions from NN to ΞΞ are calculated simultaneously by using large scale computer resources. In this contribution, we focus on the strangeness S = −1 channels of the hyperon interactions by means of HAL QCD method. Four sets of three potentials (the
3
S
1
−
3
D
1
central,
3
S
1
−
3
D
1
tensor, and the
1
S
0
central potentials) are presented for the ∑
N
− ∑
N
(the isospin
I
= 3/2) diagonal, the ∧
N
− ∧
N
diagonal, the ∧
N
→ ∑
N
transition, and the ∑
N
− ∑
N
(
I
= 1/2) diagonal interactions. Scattering phase shifts for ∑
N
(
I
= 3/2) system are presented.
Understanding the evolution of matter in the universe is one of the most fascinating challenges in nuclear physics. Baryons consist of almost all masses of visible matter, and central to this study ...is the determination of interactions among baryons (baryon forces).
Hyperon-nucleon and hyperon-hyperon interactions are important in studying the properties of hypernuclei in hypernuclear physics. However, unlike the nucleons which are quite stable, hyperons are ...unstable so that the direct scattering experiments are difficult, which leads to the large uncertainty in the phenomenological determination of hyperon potentials. In this talk, we use the gauge configurations generated at the (almost) physical point (
m
π
= 146 MeV) on a huge spatial volume (8:1fm)
4
to present our latest result on the hyperon-hyperon potentials in S = −3 sector (Ξ∑ single channel and Ξ∑- ΞΛ; coupled channel) from the Nambu-Bethe-Salpeter wave functions based on the HAL QCD method with improved statistics.
Abstract
Three-nucleon forces (3NF) are investigated from two-flavor lattice QCD simulations. We utilize the Nambu-Bethe-Salpeter (NBS) wave function to determine two-nucleon forces (2NF) and 3NF in ...the same framework. As a first exploratory study, we extract 3NF in which three nucleons are aligned linearly with an equal spacing. This is the simplest geometrical configuration which reduces the huge computational cost of calculating the NBS wave function. Quantum numbers of the three-nucleon system are chosen to be (I, JP) = (1/2,1/2+) (the triton channel). Lattice QCD simulations are performed using Nf = 2 dynamical clover fermion configurations at the lattice spacing of a = 0.156 fm on a 163 × 32 lattice with a large quark mass corresponding to mπ = 1.13 GeV. We find repulsive 3NF at short distance in the triton channel. Several sources of systematic errors are also discussed.
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