AbstractIn this work, we study the strong decays of the newly observed $$\varXi (1620)^0$$
Ξ
(
1620
)
0
assuming that it is a meson-baryon molecular state of $$\varLambda {\bar{K}}$$
Λ
K
¯
and $$\varSigma {\bar{K}}$$
Σ
K
¯
. We consider four possible spin-parity assignments $$J^P=1/2^{\pm }$$
J
P
=
1
/
2
±
and $$3/2^{\pm }$$
3
/
2
±
for the $$\varXi (1620)^0$$
Ξ
(
1620
)
0
, and evaluate its partial decay width into $$\varXi \pi $$
Ξ
π
and $$\varXi \pi \pi $$
Ξ
π
π
via hadronic loops with the help of effective Lagrangians. In comparison with the Belle data, the calculated decay width favors the spin-party assignment $$1/2^-$$
1
/
2
-
while the other spin-parity assignments do not yield a decay width consistent with data in the molecule picture. We find that about 52–68% of the total width comes from the $${\bar{K}}\varLambda $$
K
¯
Λ
channel, while the rest is provided by the $${\bar{K}}\varSigma $$
K
¯
Σ
channel. As a result, both channels are important in explaining the strong decay of the $$\varXi (1620)^0$$
Ξ
(
1620
)
0
. In addition, the transition $$\varXi (1620)^0\rightarrow \pi \varXi $$
Ξ
(
1620
)
0
→
π
Ξ
is the main decay channel in the $$J^{P}=1/2^{-}$$
J
P
=
1
/
2
-
case, which almost saturates the total width. These information are helpful to further understand the nature of the $$\varXi (1620)^0$$
Ξ
(
1620
)
0
.
Measurements of the Z partial decay width into $c\bar c$ and multiplicity of charm quarks per b decay
