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arXiv · hep-th/0612187

Baryons in Holographic QCD

Kanabu Nawa·Hideo Suganuma·Toru Kojo
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Abstract

We study the baryon in holographic QCD with $D4/D8/\bar{D8}$ multi-$D$ brane system. In holographic QCD, the baryon appears as a topologically non-trivial chiral soliton in a four-dimensional effective theory of mesons. We call this topological soliton as Brane-induced Skyrmion. Some review of $D4/D8/\bar{D8}$ holographic QCD is presented from the viewpoints of recent hadron physics and phenomenologies. Four-dimensional effective theory with pions and $ρ$ mesons is uniquely derived from the non-abelian Dirac-Born-Infeld (DBI) action of $D8$ brane with $D4$ supergravity background, without small amplitude expansion of meson fields to discuss chiral solitons. For the hedgehog configuration of pion and $ρ$-meson fields, we derive the energy functional and the Euler-Lagrange equation of Brane-induced Skyrmion from the meson effective action induced by holographic QCD. Performing the numerical calculation, we obtain the pion profile $F(r)$ and the $ρ$-meson profile $G(r)$ of the Brane-induced Skyrmion, and estimate its total energy, energy density distribution, and root-mean-square radius. These results are compared with the experimental quantities of baryons and also with the profiles of standard Skyrmion without $ρ$ mesons. We analyze interaction terms of pions and $ρ$ mesons in Brane-induced Skyrmion, and consider the role of $ρ$-meson component appearing in baryons.

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Kanabu Nawa, Hideo Suganuma, Toru Kojo. 2007-04-26. Baryons in Holographic QCD. https://doi.org/10.1103/physrevd.75.086003

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