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تسجيل مستخدم جديدWhether new data on $D_sto f_0(980) e^+ u_e$ can be understood if $f_0(980)$ consists of only the conventional $qbar{q}$ structure
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Only two isospin-singlet scalar mesons $f_0(600)$ ($sigma$) and $f_0(980)$ exist below 1 GeV, so that it is natural to suppose that they are two energy eigenstates which are mixtures of ${1oversqrt 2}(ubar u+dbar d)$ and $sbar s$. Is this picture right? Generally, it is considered that $f_0(600)$ mainly consists of ${1oversqrt 2}(ubar u+dbar d)$, if so, the dominant component of $f_0(980)$ should be $sbar s$. The recent measurement of the CLEO collaboration on the branching ratio of $D_sto f_0(980) e^+ u_e$ provides an excellent opportunity to testify the structure of $f_0(980)$, namely whether the data can be understood as long as it consists of mainly the conventional $qbar q$ structure. We calculate the form factors of $D_sto f_0(980)$ in the light-front quark model (LFQM) and the corresponding branching ratio of the semileptonic decay. By fitting the data, we obtain the mixing angle $phi$. The obtained mixing angle shows that the $sbar s$ component in $f_0(980)$ may not be dominant.
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The $a_0^0(980)-f_0(980)$ mixing is one of the most potential tools to learn about the nature of $a_0^0(980)$ and $f_0(980)$. Using the $f_0(980)$-$a_0^0(980)$ mixing intensity $xi_{af}$ measured recently at BESIII, we calculate the the branching rat
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We make a theoretical study of the $eta(1405) to pi^{0} f_0(980)$ and $eta(1405) to pi^{0} a_0(980)$ reactions with an aim to determine the isospin violation and the mixing of the $f_0(980)$ and $a_0(980)$ resonances. We make use of the chiral unitar
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lyzing the BESIII and {it BABAR} measurements, we conclude that the $f_0(980)$ state, dynamically generated from the $S$-wave pseudoscalar-pseudoscalar interaction, gives the dominant contribution close to the $K^+K^-$ threshold in the $K^+K^-$ invariant mass distribution of the decay $D_s^+to K^+ K^- pi^+$ in $S$-wave. On the other hand, our results imply that the lineshape adopted by BESIII and {it BABAR} for the resonances $a_0(980)$ and $f_0(980)$ is not advisable in the fit to the data close to the $K^+K^-$ threshold.
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