Study of D_{s}^{+}→f_{0}(980)ρ^{+} and ϕπ^{+} Decays through D_{s}^{+}→π^{+}π^{+}π^{-}π^{0}

Area of Science:

• High-energy particle physics
• Experimental particle physics
• Quantum chromodynamics

Background:

• The D_{s}^{+} meson is a key probe for studying strong interaction dynamics.
• Understanding multi-body decays of heavy mesons is crucial for refining theoretical models.
• Previous studies lacked detailed amplitude analyses for specific D_{s}^{+} decay channels.

Purpose of the Study:

• To perform the first amplitude analysis of D_{s}^{+}→π^{+}π^{+}π^{-}π^{0} decays.
• To report the observation and branching fractions of specific decay modes.
• To measure the relative branching fraction of ϕ→π^{+}π^{-}π^{0} decays.

Main Methods:

• Utilized electron-positron collision data from the BESIII detector.
• Analyzed data collected at center-of-mass energies between 4.128 and 4.226 GeV.
• Performed amplitude analysis to determine decay properties and branching fractions.

Main Results:

• Observed the decay D_{s}^{+}→f_{0}(980)ρ(770)^{+} with >10σ statistical significance.
• Determined branching fractions B(D_{s}^{+}→π^{+}π^{+}π^{-}π^{0}|_{non-η})=(2.04±0.08_{stat}±0.05_{syst})% and B(D_{s}^{+}→ηπ^{+})=(1.56±0.09_{stat}±0.04_{syst})%.
• Measured the relative branching fraction [B(ϕ(1020)→π^{+}π^{-}π^{0})/B(ϕ(1020)→K^{+}K^{-})]=0.230±0.014_{stat}±0.010_{syst}, deviating from the world average by >4σ.

Conclusions:

• The amplitude analysis provides a detailed understanding of D_{s}^{+}→π^{+}π^{+}π^{-}π^{0} decays.
• The observed decay and measured branching fractions offer valuable data for theoretical comparisons.
• The significant deviation in the ϕ decay channel warrants further investigation and may indicate new physics.