[신간의 별자리x] 우리/미술, 그리고 ‘슬픔의 박물관’

비만아 부모의 돌봄 경험: q 방법론

KamLAND has measured the flux of nu;(e)'s from distant nuclear reactors. We find fewer nu;(e) events than expected from standard assumptions about nu;(e) propagation at the 99.95% C.L. In a 162 ton.yr exposure the ratio of the observed inverse beta-decay events to the expected number without nu;(e) disappearance is 0.611+/-0.085(stat)+/-0.041(syst) for nu;(e) energies >3.4 MeV. In the context of two-flavor neutrino oscillations with CPT invariance, all solutions to the solar neutrino problem except for the "large mixing angle" region are excluded.

First Results from KamLAND: Evidence for Reactor Anti-Neutrino Disappearance

The hidden-charm pentaquark and tetraquark states

A large number of experimental discoveries especially in the heavy quarkonium sector that did not at all fit to the expectations of the until then very successful quark model led to a renaissance of hadron spectroscopy Among various explanations of the internal structure of these excitations, hadronic molecules, being analogues of light nuclei, play a unique role since for those predictions can be made with controlled uncertainty We review experimental evidences of various candidates of hadronic molecules, and methods of identifying such structures Nonrelativistic effective field theories are the suitable framework for studying hadronic molecules, and are discussed in both the continuum and finite volumes Also pertinent lattice QCD results are presented Further, we discuss the production mechanisms and decays of hadronic molecules, and comment on the reliability of certain assertions often made in the literature

Hadronic molecules

In this article, we distinguish the charge conjunctions of the interpolating currents, calculate the contributions of the vacuum condensates up to dimension 10 in a consistent way in the operator product expansion, study the masses and pole residues of the ${J}^{PC}={1}^{+\ifmmode\pm\else\textpm\fi{}}$ hidden charmed tetraquark states with the QCD sum rules, and explore the energy-scale dependence in detail for the first time. The predictions ${M}_{X}=3.8{7}_{\ensuremath{-}0.09}^{+0.09}\text{ }\text{ }\text{GeV}$ and ${M}_{Z}=3.9{1}_{\ensuremath{-}0.09}^{+0.11}\text{ }\text{ }\text{GeV}$ support assigning the $X(3872)$ and ${Z}_{c}(3900)$ [or ${Z}_{c}(3885)$] as the ${1}^{++}$ and ${1}^{+\ensuremath{-}}$ diquark-antidiquark type tetraquark states, respectively.

Analysis of the X(3872), Z c (3900), and Z c (3885) as axial-vector tetraquark states with QCD sum rules

In this article, we construct the diquark–diquark–antiquark type interpolating currents, and we study the masses and pole residues of the $$J^P={\frac{3}{2}}^-$$
 and $${\frac{5}{2}}^+$$
 hidden charm pentaquark states in detail with the QCD sum rules by calculating the contributions of the vacuum condensates up to dimension-10 in the operator product expansion. In the calculations, we use the formula $$\mu =\sqrt{M^2_{P_c}-(2{\mathbb {M}}_c)^2}$$
 to determine the energy scales of the QCD spectral densities. The present predictions favor assigning $$P_c(4380)$$
 and $$P_c(4450)$$
 to be the $${\frac{3}{2}}^-$$
 and $${\frac{5}{2}}^+$$
 pentaquark states, respectively.

/pdf/analysis-of-p-c-4380-and-p-c-4450-as-pentaquark-states-in-1i4xdf5pxs.pdf

Analysis of P_c(4380) and P_c(4450) as pentaquark states in the diquark model with QCD sum rules

In this article, we construct both the color singlet–singlet type and the octet–octet type currents to interpolate $$X(3872)$$
 , $$Z_c(3900)$$
 , and $$Z_b(10610)$$
 , and we calculate the vacuum condensates up to dimension-10 in the operator product expansion. Then we study the axial-vector hidden charm and hidden bottom molecular states with the QCD sum rules, explore the energy-scale dependence of the QCD sum rules for the heavy molecular states in details, and we use the formula $$\mu =\sqrt{M^2_{X/Y/Z}-(2{\mathbb {M}}_Q)^2}$$
 with the effective masses $${\mathbb {M}}_Q$$
 to determine the energy scales. The numerical results support assigning $$X(3872)$$
 , $$Z_c(3900)$$
 , and $$Z_b(10610)$$
 as the color singlet–singlet type molecular states with $$J^{PC}=1^{++}$$
 , $$1^{+-}$$
 , $$1^{+-}$$
 , respectively, more theoretical and experimental work is still needed to distinguish the molecule and tetraquark assignments; while there are no candidates for the color octet–octet type molecular states.

/pdf/possible-assignments-of-the-x-3872-z-c-3900-and-z-b-10610-as-4866ri8dps.pdf

Zhi-Gang Wang

Papers

Analysis of the X(3872), Z c (3900), and Z c (3885) as axial-vector tetraquark states with QCD sum rules

Analysis of P_c(4380) and P_c(4450) as pentaquark states in the diquark model with QCD sum rules

Possible assignments of the $X(3872)$, $Z_c(3900)$ and $Z_b(10610)$ as axial-vector molecular states

Analysis of Y(2175) as a tetraquark state with QCD sum rules

The Zb(10610) and Zb(10650) as axial-vector tetraquark states in the QCD sum rules