A
bstract
Using data samples with an integrated luminosity of 19 fb
−
1
at twenty-eight center-of-mass energies from 3.872 GeV to 4.700 GeV collected with the BESIII detector at the BEPCII ...electron-positron collider, the process
e
+
e
−
→
ηπ
+
π
−
and the intermediate process
e
+
e
−
→
ηρ
0
are studied for the first time. The Born cross sections are measured. No significant resonance structure is observed in the cross section lineshape.
A
bstract
Based on
e
+
e
−
collision samples corresponding to an integrated luminosity of 4.4 fb
−
1
collected with the BESIII detector at center-of-mass energies between 4
.
6 GeV and 4
.
7 GeV, a ...partial wave analysis of the charmed baryon hadronic decay
Λ
c
+
→
Λ
π
+
π
0
is performed, and the decays
Λ
c
+
→
Λ
ρ
(770)
+
and
Λ
c
+
→
Σ(1385)
π
are studied for the first time. Making use of the world-average branching fraction
B
Λ
c
+
→
Λ
π
+
π
0
, their branching fractions are determined to be
B
Λ
c
+
→
Λ
ρ
770
+
=
4.06
±
0.30
±
0.35
±
0.23
×
10
−
2
,
B
Λ
c
+
→
Σ
1385
+
π
0
=
5.86
±
0.49
±
0.52
±
0.35
×
10
−
3
,
B
Λ
c
+
→
Σ
1385
0
π
+
=
6.47
±
0.59
±
0.66
±
0.38
×
10
−
3
,
where the first uncertainties are statistical, the second are systematic, and the third are from the uncertainties of the branching fractions
B
Λ
c
+
→
Λ
π
+
π
0
and
B
Σ
1385
→
Λ
π
. In addition, the decay asymmetry parameters are measured to be
α
Λ
ρ
(770)+
= − 0.763 ± 0.053 ± 0.045,
α
Σ
1385
+
π
0
=
−
0.917
±
0.069
±
0.056
, and
α
Σ
1385
0
π
+
=
−
0.789
±
0.098
±
0.056
.
A
bstract
Using 2.93 fb
−
1
of
e
+
e
−
collision data collected with the BESIII detector at the center-of-mass energy 3.773 GeV, we perform the first amplitude analysis of the decay
D
+
→
K
S
0
π
+
π
...0
π
0
and determine the relative magnitudes and phases of different intermediate processes. The absolute branching fraction of
D
+
→
K
S
0
π
+
π
0
π
0
is measured to be (2.888
±
0.058
stat
.
±
0.069
syst
.
)%. The dominant intermediate processes are
D
+
→
K
S
0
a
1
(1260)
+
(
→ ρ
+
π
0
) and
D
+
→
K
¯
*0
ρ
+
, with branching fractions of (8.66
±
1.04
stat
.
±
1.39
syst
.
)
×
10
−
3
and (9.70
±
0.81
stat
.
±
0.53
syst
.
)
×
10
−
3
, respectively.
A
bstract
The singly Cabibbo-suppressed decay
D
s
+
→
K
+
π
+
π
−
π
0
is observed by using a data set corresponding to an integrated luminosity of 6.32 fb
−
1
recorded by the BESIII detector at the ...centre-of-mass energies between 4.178 and 4.226 GeV. The first amplitude analysis of
D
s
+
→
K
+
π
+
π
−
π
0
reveals the sub-structures in this decay and determines the fractions and relative phases of different intermediate processes. The dominant intermediate process is
D
s
+
→
K
*0
ρ
+
, with a fit fraction of (40
.
5 ± 2
.
8
stat
.
± 1
.
5
syst
.
)%. With the detection efficiency based on our amplitude analysis, the absolute branching fraction for
D
s
+
→
K
+
π
+
π
−
π
0
is measured to be (9
.
75
±
0
.
54
stat
.
±
0
.
17
syst
.
)
×
10
−
3
.
A
bstract
A search for the hadronic decays of the
h
c
meson to the final states
p
p
¯
π
+
π
−
π
0
,
p
p
¯
η
, and
p
p
¯
π
0
via the process
ψ
(3686) →
π
0
h
c
is performed using (4
.
48
±
0
.
03)
×
...10
8
ψ
(3686) events collected with the BESIII detector. The decay channel
h
c
→
p
p
¯
η
is observed for the first time with a significance greater than 5
σ
and a branching fraction of (6
.
41
±
1
.
74
±
0
.
53
±
1
.
00)
×
10
−
4
, where the uncertainties are statistical, systematic, and that from the branching fraction of
ψ
(3686) →
π
0
h
c
. Strong evidence for the decay
h
c
→
p
p
¯
π
+
π
−
π
0
is found with a significance of 4
.
9
σ
and a branching fraction of (3
.
84
±
0
.
83
±
0
.
69
±
0
.
58)
×
10
−
3
. The significances include systematic uncertainties. No clear signal of the decay
h
c
→
p
p
¯
π
0
is found, and an upper limit of 6
.
59
×
10
−
4
on its branching fraction is set at the 90% confidence level.
A
bstract
Using data collected with the BESIII detector in
e
+
e
−
collisions at center-of-mass energies between 4.178 and 4.226 GeV and corresponding to 6.32 fb
−
1
of integrated luminosity, we ...report the amplitude analysis and branching-fraction measurement of the
D
s
+
→ π
+
π
0
η
′ decay. We find that the dominant intermediate process is
D
s
+
→ ρ
+
η
′ and the significances of other resonant and nonresonant processes are all less than 3
σ
. The upper limits on the branching fractions of
S
-wave and
P
-wave nonresonant components are set to 0.10% and 0.74% at the 90% confidence level, respectively. In addition, the branching fraction of the
D
s
+
→ π
+
π
0
η
′ decay is measured to be (6
.
15
±
0
.
25(stat
.
)
±
0
.
18(syst
.
))%, which receives significant contribution only from
D
s
+
→ ρ
+
η
′ according to the amplitude analysis.
A
bstract
Using data samples with an integrated luminosity of 6
.
4 fb
−
1
collected by the BESIII detector operating at the BEPCII storage ring, the process of
e
+
e
−
→
γϕJ/ψ
is studied. The ...processes of
e
+
e
−
→
ϕχ
c
1
,
c
2
,
χ
c
1
,
c
2
→
γJ/ψ
are observed with a significance of more than 10
σ
. The
s
-dependent cross section of
e
+
e
−
→
ϕχ
c
1
,
c
2
is measured between 4.600 and 4.951 GeV, and evidence of a resonance structure is found for the first time in the
ϕχ
c
2
process. We also search for the processes of
e
+
e
−
→
γX
(4140),
γX
(4274) and
γX
(4500) via the
γϕJ/ψ
final state, but no obvious structures are found. The upper limits on the production cross section times the branching fraction for these processes at the 90% confidence level are reported.
A
bstract
The Born cross sections of the processes
e
+
e
−
→
ωπ
0
and
e
+
e
−
→
ωη
are measured at center-of-mass energies between 3.773 and 4.701 GeV using a total integrated luminosity of 22.7 fb
−
...1
collected with the BESIII detector operating at the BEPCII collider. A simple
s
−n
dependence for the continuum process can describe the measured Born cross sections. No significant contributions from the
ψ
(4160),
Y
(4230),
Y
(4360),
ψ
(4415),
Y
(4660) resonances are found, which indicates relative small branching fractions for these resonances into the
ωπ
0
and
ωη
final states.
Observation of e+e−→ π0π0ψ2(3823) Bai, X. H.; Balossino, I.; Bettoni, D. ...
The journal of high energy physics,
16/2, Letnik:
2023, Številka:
2
Journal Article
Recenzirano
Odprti dostop
A
bstract
Using a data sample corresponding to an integrated luminosity of 11.3 fb
−
1
collected at center-of-mass energies from 4.23 to 4.70 GeV with the BESIII detector, we observe the process
e
+
...e
−
→ π
0
π
0
ψ
2
(3823) for the first time with a statistical significance of 6
.
0 standard deviations. The ratio of average cross sections for
e
+
e
−
→ π
0
π
0
ψ
2
(3823) and
π
+
π
−
ψ
2
(3823) is determined to be
R
=
σ
e
+
e
−
→
π
0
π
0
ψ
2
3823
σ
e
+
e
−
→
π
+
π
−
ψ
2
3823
=
0.57
±
0.14
±
0.05
, which is consistent with expectations from isospin symmetry. Here and below, the first uncertainties are statistical and the second are systematic. The mass of the
ψ
2
(3823) is measured to be
M
ψ
2
(3823) = 3824
.
5
±
2
.
4
±
1
.
0 MeV/
c
2
. Due to the limited data sample, an upper limit of 18.8 MeV at 90% confidence level is set on the intrinsic width of
ψ
2
(3823).
A
bstract
Based on
e
+
e
−
collision data collected by the BESIII detector at the BEPCII collider at center-of-mass energies from 2.000 to 3.080 GeV, a partial-wave analysis is performed for the ...process
e
+
e
−
→ K
+
K
−
π
0
. The Born cross section of the process
e
+
e
−
→ K
+
K
−
π
0
and its subprocesses
e
+
e
−
→ ϕπ
0
,
K
*+
(892)
K
−
and
K
2
∗
+
(1430)
K
−
are measured. The results for
e
+
e
−
→ K
+
K
−
π
0
and
ϕπ
0
are consistent with the BaBar measurements and with improved precision. By analyzing the cross sections of the subprocesses
e
+
e
−
→ K
*+
(892)
K
−
and
K
2
∗
+
(1430)
K
−
, a structure with mass
M
R
= (2190 ± 19 ± 37) MeV/
c
2
and width Γ
R
= (191 ± 28 ± 60) MeV is observed with a combined statistical significance of 7.1
σ
. The measured resonance parameters suggest it can be identified as the
ϕ
(2170), thus the results provide valuable input to understand the internal nature of this state.
