Study of the Decay $D_s^{+}\to {\pi }^{+}{\pi }^{+}{\pi }^{-}\eta$ and Observation of the W-annihilation Decay $D_s^{+}\to a_0(980{)}^{+}{\rho }^0$

Abstract

The decay $D_s^{+}\to {\pi }^{+}{\pi }^{+}{\pi }^{-}\eta$ is observed for the first time, using $e^{+}{e}^{-}$ collision data corresponding to an integrated luminosity of 6.32 fb${}^{-1}$, collected by the BESIII detector at center-of-mass energies between 4.178 and 4.226 GeV. The absolute branching fraction for this decay is measured to be $\mathcal{B}(D_s^{+}\to {\pi }^{+}{\pi }^{+}{\pi }^{-}\eta )=(3.12\pm 0.13_{stat.}\pm 0.09_{syst.})$%. The first amplitude analysis of this decay reveals the sub-structures in $D_s^{+}\to {\pi }^{+}{\pi }^{+}{\pi }^{-}\eta$ and determines the relative fractions and the phases among these sub-structures. The dominant intermediate process is $D_s^{+}\to a_1(1260{)}^{+}\eta ,a_1(1260{)}^{+}\to \rho (770{)}^0{\pi }^{+}$ with a branching fraction of $(1.73\pm 0.14_{stat.}\pm 0.08_{syst.})$%. We also observe the W-annihilation process $D_s^{+}\to a_0(980{)}^{+}\rho (770{)}^0$, $a_0(980{)}^{+}\to {\pi }^{+}\eta$ with a branching fraction of $(0.21\pm 0.08_{stat.}\pm 0.05_{syst.})$%, which is larger than the branching fractions of other measured pure W-annihilation decays by one order of magnitude.

8 pages, 3 figures

References in corpus (4)

• Amplitude analysis of the ${\chi }_{c1}\to \eta {\pi }^{+}{\pi }^{-}$ decays
• Resonant $a_0(980)$ state in triangle rescattering $D_s^{+}\to {\pi }^{+}{\pi }^0\eta$ decays
• Amplitude analysis and branching fraction measurement of $D_s^{+}\to K^{+}{K}^{-}{\pi }^{+}$
• Amplitude analysis and branching-fraction measurement of $D_s^{+}\to K_S^0{K}^{-}{\pi }^{+}{\pi }^{+}$

Cited by in corpus (9)

• Pole position of the $a_1(1260)$ resonance in a three-body unitary framework
• Measurement of the absolute branching fraction of the inclusive decay $D_s^{+}\to {\pi }^{+}{\pi }^{+}{\pi }^{-}X$
• Search for the semileptonic decay $D_s^{+}\to {\pi }^0{e}^{+}{\nu }_e$
• Evidence for $B^{-}\to D^{\ast \ast 0}{\tau }^{-}\overline{{\nu }_{\tau }}$ decays
• Study of $D_s^{+}\to f_0(980){\rho }^{+}$ and $\varphi {\pi }^{+}$ decays through $D_s^{+}\to {\pi }^{+}{\pi }^{+}{\pi }^{-}{\pi }^0$
• Form factors of $B_{(s)}$ to light scalar mesons with the $B$-meson LCSR
• Study of the light scalar $a_0(980)$ through the decay $D^0\to a_0(980{)}^{-}{e}^{+}{\nu }_e$ with $a_0(980{)}^{-}\to \eta {\pi }^{-}$
• Amplitude Analysis of the Isospin-Violating Decay $J/\psi \to \gamma \eta {\pi }^0$
• Roles of $a_0(980)$ and $a_0(1710)$ in Cabibbo-suppressed process $D^{+}\to {\pi }^0{\pi }^{+}\eta$