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$bar{b}bar{b}ud$ tetraquark resonances in the Born-Oppenheimer approximation using lattice QCD potentials

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 نشر من قبل Martin Pflaumer
 تاريخ النشر 2018
  مجال البحث
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We study tetraquark resonances using lattice QCD potentials for a pair of static antiquarks $bar{b}bar{b}$ in the presence of two light quarks $ud$. The system is treated in the Born-Oppenheimer approximation and we use the emergent wave method. We focus on the isospin $I=0$ channel, but consider different orbital angular momenta $l$ of the heavy antiquarks $bar{b}bar{b}$. We extract the phase shifts and search for $mbox{S}$ and $mbox{T}$ matrix poles on the second Riemann sheet. For orbital angular momentum $l=1$ we find a tetraquark resonance with quantum numbers $I(J^P)=0(1^-)$, resonance mass $m=10576^{+4}_{-4} , textrm{MeV}$ and decay width $Gamma= 112^{+90}_{-103} textrm{MeV}$, which can decay into two $B$ mesons.



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We study tetraquark resonances with lattice QCD potentials computed for a static bbar bbar pair in the presence of two lighter quarks u d, the Born-Oppenheimer approximation and the emergent wave method. As a proof of concept we focus on the system w ith isospin I = 0, but consider different relative angular momenta l of the heavy quarks bbar bbar. For l=0 a bound state has already been predicted with quantum numbers I(JP) = 0(1+). Exploring various angular momenta we now compute the phase shifts and search for S and T matrix poles in the second Riemann sheet. We predict a tetraquark resonance for l =1, decaying into two B mesons, with quantum numbers I(JP) = 0(1-), mass m = 10 , 576^{+4}_{-4} MeV} and decay width Gamma = 112^{+90}_{-103} MeV.
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