10,958 research outputs found
Baryons with U_L(3)*U_R(3) Chiral Symmetry IV: Interactions with Chiral (8,1)+(1,8) Vector and Axial-vector Mesons and Anomalous Magnetic Moments
We construct all SU_L(3)*SU_R(3) chirally invariant anomalous magnetic, i.e.
involving a Pauli tensor and one-derivative, interactions of one
chiral-[(8,1)+(1,8)] meson field with chiral-[(6,3)+(3,6)],
[(3,\bar3)+(\bar3,3)], and [(8,1)+(1,8)] baryon fields and their "mirror"
images. We find strong chiral selection rules: e.g. there is only one
off-diagonal chirally symmetric anomalous magnetic interaction between J=1/2
fields belonging to the [(6,3)+(3,6)] and the [(3,\bar3)+(\bar3,3)] chiral
multiplets. We also study the chiral selection rules for the anomalous magnetic
interactions of the [(3,\bar3)+(\bar3,3)] and the [(8,1)+(1,8)] baryon fields.
Again, no diagonal and only one off-diagonal chiral SU_L(3)*SU_R(3) interaction
of this type is allowed, that turns out also to conserve the U_A(1) symmetry.
We calculate the F/D ratios for the baryons' anomalous magnetic moments
predicted by these interactions in the SU(3) symmetry limit and find that only
the [(6,3)+(3,6)]-[(3,\bar3)+(\bar3,3)] one, reproduces F/D=1/3, in close
proximity to the value extracted from experiment.Comment: 16 pages, 2 tables, accepted by PR
Baryon Fields with U_L(3) \times U_R(3) Chiral Symmetry: Axial Currents of Nucleons and Hyperons
We use the conventional F and D octet and decimet generator matrices to
reformulate chiral properties of local (non-derivative) and one-derivative
non-local fields of baryons consisting of three quarks with flavor SU(3)
symmetry that were expressed in SU(3) tensor form in Ref. [12]. We show
explicitly the chiral transformations of the [(6,3)\oplus(3,6)] chiral
multiplet in the "SU(3) particle basis", for the first time to our knowledge,
as well as those of the (3,\bar{3}) \oplus (\bar{3}, 3), (8,1) \oplus (1,8)
multiplets, which have been recorded before in Refs. [4,5]. We derive the
vector and axial-vector Noether currents, and show explicitly that their zeroth
(charge-like) components close the SU_L(3) \times SU_R(3) chiral algebra. We
use these results to study the effects of mixing of (three-quark) chiral
multiplets on the axial current matrix elements of hyperons and nucleons. We
show, in particular, that there is a strong correlation, indeed a definite
relation between the flavor-singlet (i.e. the zeroth), the isovector (the
third) and the eighth flavor component of the axial current, which is in decent
agreement with the measured ones.Comment: one typo correction, and accepted by PR
Analysis of energy transfer efficiency in UAV-enabled wireless networks
Wireless power transfer (WPT) is a promising charging technology for battery-limited sensors. In this paper, we study the energy transfer in a wireless network using an unmanned aerial vehicle (UAV). Instead of charging the remote wireless sensors directly from the access point (AP), we study the schemes of using a UAV to charge the remote wireless sensors after it is charged by the AP. To this end, two schemes are proposed. The performances of these two schemes are examined and compared with the conventional scheme without using a UAV. A distance threshold beyond which the new schemes have superiority over the conventional scheme is derived by solving energy equations. Numerical results show that the proposed schemes can achieve significantly higher energy efficiency than the conventional scheme when the transmission distance is within the derived critical range
The Strong Decay Patterns of the Exotic Hybrid Mesons
We calculate the coupling constants of the decay modes
within the framework of the light-cone QCD sum rule. Then we calculate the
partial width of these decay channels, which differ greatly from the existing
calculations using phenomenological models. For the isovector state,
the dominant decay modes are . For its isoscalar partner, its
dominant decay mode is . We also discuss the possible search of the
state at BESIII, for example through the decay chains or where can
be reconstructed through the decay modes
or . Hopefully the present work will be helpful to the
experimental establishment of the hybrid meson.Comment: 14 pages, 10 figure
The I^G J^{PC}=1^- 1^{-+} Tetraquark States
We study the tetraquark states with I^G J^{PC}=1^- 1^{-+} in the QCD sum
rule. After exhausting all possible flavor structures, we analyses both the SVZ
and finite energy sum rules. Both approaches lead to a mass around 1.6 GeV for
the state with the quark contents q q q_bar q_bar, and around 2.0 GeV for the
state with the quark contents q s q_bar s_bar. The flavor structure 3_bar *
6_bar + 6 * 3 is preferred. Our analysis strongly indicates that both pi1(1600)
and pi1(2015) are also compatible with the exotic tetraquark interpretation,
which are sometimes labeled as candidates of the 1^{-+} hybrid mesons. Moreover
one of their dominant decay modes is a pair of axial-vector and pseudoscalar
mesons such as b1(1235) pi, which is sometimes considered as the characteristic
decay mode of the hybrid mesons.Comment: 18 pages, 14 figures, revised version to appear in Phys. Rev.
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