Full text
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| Author(s): |
Stefano Ivo Finazzo
Total Authors: 1
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| Document type: | Master's Dissertation |
| Press: | São Paulo. |
| Institution: | Universidade de São Paulo (USP). Instituto de Física (IF/SBI) |
| Defense date: | 2012-02-02 |
| Examining board members: |
Marina Nielsen;
Renato Higa;
Ricardo D'Elia Matheus
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| Advisor: | Marina Nielsen |
| Abstract | |
Recently, the CDF collaboration found evidence for a new charmonium-like resonance on the $B^{\\pm} ightarrow K^{\\pm} J/\\psi \\phi$ invariant mass spectrum. This resonance has a mass of $4274.4^{+8.4}_{-6.7} \\, \\mathrm(stat) \\, \\pm 1.9 (syst) \\, \\mathrm{MeV}$ - thus being named the Y(4274) resonance - and total decay width of $32.3^{+21.9}_{-15.3} \\, \\mathrm(stat) \\, \\pm 7.6 (syst) \\, \\mathrm{MeV}$. The statistical significance of this structure is approximately 3.1 $\\sigma$. Using the QCD sum rules and a molecular model similar to a model previously proposed to explain the strutcture of the Y(3930) and Y(4140) resonances, we studied the Y(4274) as the hadronic molecule $D_{s0} \\bar{D}_s + h.c.$ with $J^{PC}=0^{-+}$ and its molecular partner, the molecule $D_{0} \\bar{D} + h.c.$. We obtained that $m_{D_{s0} \\bar{D}_{s}} = (4.78 \\pm 0.54) \\, \\mathrm{GeV}$, a result that is compatible, within the error estimates, with the mass of Y(4274). For its molecular partner, we have that $m_{D_{0} \\bar{D}} = (4.55 \\pm 0.49) \\, \\mathrm{GeV}$. The analogous bottomonium-like molecular states, $B_{s0} \\bar{B}_s + h.c.$ e $B_{0} \\bar{B}+h.c.$, were also studied. (AU) | |
| FAPESP's process: | 10/02320-4 - Study of the Y(3930) resonance using QCD sum rules. |
| Grantee: | Stefano Ivo Finazzo |
| Support Opportunities: | Scholarships in Brazil - Master |