AbstractIn the present work, we investigate the decays of $$B^{0}_{(s)} \rightarrow \phi \pi ^{+}\pi ^{-}$$
B
(
s
)
0
→
ϕ
π
+
π
-
with the final state interaction based on the chiral unitary approach. In the final state interaction of the $$\pi ^+\pi ^-$$
π
+
π
-
with its coupled channels, we study the effects of the $$\eta \eta $$
η
η
channel in the two-body interaction for the reproduction of the $$f_{0}(980)$$
f
0
(
980
)
state, where its contribution to the $$f_{0}(980)$$
f
0
(
980
)
state can be ignored. Our results for the $$\pi ^+\pi ^-$$
π
+
π
-
invariant mass distributions of the decay $$B^{0}_{s} \rightarrow \phi \pi ^{+}\pi ^{-}$$
B
s
0
→
ϕ
π
+
π
-
describe the experimental data up to 1 GeV well, with the resonance contributions from the $$f_{0}(980)$$
f
0
(
980
)
and $$\rho $$
ρ
. For the predicted invariant mass distributions of the $$B^{0} \rightarrow \phi \pi ^{+}\pi ^{-}$$
B
0
→
ϕ
π
+
π
-
decay, we find that the contributions from the $$f_{0}(500)$$
f
0
(
500
)
are significant, but not from the $$f_{0}(980)$$
f
0
(
980
)
state. With some experimental branching ratios to determine the production vertex factors, we make predictions for the branching ratios of the other decay channels, including the vector mesons, in the $$B^0_{(s)}$$
B
(
s
)
0
decays, some of which are consistent with the experimental measurements within the uncertainties.