Glueball Decay Rates in the Witten-Sakai-Sugimoto Model

Jan 30, 2015
24 pages
Published in:
  • Phys.Rev.D 91 (2015) 10, 106002,
  • Phys.Rev.D 93 (2016) 10, 109903 (erratum)
  • Published: May 14, 2015
e-Print:
Report number:
  • TUW-15-01

Citations per year

2015201720192021202305101520
Abstract: (APS)
We revisit and extend previous calculations of glueball decay rates in the Sakai-Sugimoto model, a holographic top-down approach for QCD with chiral quarks based on D8-D8¯ probe branes in Witten’s holographic model of nonsupersymmetric Yang-Mills theory. The rates for decays into two pions, two vector mesons, four pions, and the strongly suppressed decay into four π0 are worked out quantitatively, using a range of the ’t Hooft coupling which closely reproduces the decay rate of ρ and ω mesons and also leads to a gluon condensate consistent with QCD sum rule calculations. The lowest holographic glueball, which arises from a rather exotic polarization of gravitons in the supergravity background, turns out to have a significantly lower mass and larger width than the two widely discussed glueball candidates f0(1500) and f0(1710). The lowest nonexotic and predominantly dilatonic scalar mode, which has a mass of 1487 MeV in the Witten-Sakai-Sugimoto model, instead provides a narrow glueball state, and we conjecture that only this nonexotic mode should be identified with a scalar glueball component of f0(1500) or f0(1710). Moreover the decay pattern of the tensor glueball is determined, which is found to have a comparatively broad total width when its mass is adjusted to around or above 2 GeV.
Note:
  • 38 pages, 5 figures, 9 tables; v2: minor corrections (numerical data in tables 3, 5, and 7 on excited scalar glueballs), 2 footnotes and 2 references added; v3: corrections in table 9 (extrapolations of tensor glueball decay to masses above 2 GeV)
  • 11.25.Tq
  • 13.25.Jx
  • 14.40.Be
  • 14.40.Rt
  • glueball: decay rate
  • quantum chromodynamics: sum rule
  • gluon: condensation
  • quark: chiral
  • gauge field theory: Yang-Mills
  • holography