Cross sections of the process e+e− → π0 π0 J / ψ at center-of-mass energies between 3.808 and 4.600 GeV are measured with high precision by using 12.4 fb−1 of data samples collected with the BESIII ...detector operating at the BEPCII collider facility. A fit to the measured energy-dependent cross sections confirms the existence of the charmoniumlike state Y ( 4220 ) . The mass and width of the Y ( 4220 ) are determined to be ( 4220.4 ± 2.4 ± 2.3 ) MeV / c2 and ( 46.2 ± 4.7 ± 2.1 ) MeV , respectively, where the first uncertainties are statistical and the second systematic. The mass and width are consistent with those measured in the process e+e− → π+π− J / ψ. The neutral charmonium-like state Zc ( 3900 )0 is observed prominently in the π 0 J / ψ invariant-mass spectrum, and, for the first time, an amplitude analysis is performed to study its properties. The spin-parity of Zc ( 3900 )0 is determined to be JP = 1+, and the pole position is ( 3893.1 ± 2.2 ± 3.0 ) − i ( 22.2 ± 2.6 ± 7.0 ) MeV / c2, which is consistent with previous studies of electrically charged Zc ( 3900 )±. In addition, cross sections of e+e− → π0Zc ( 3900 )0 → π0π0 J / ψ are extracted, and the corresponding line shape is found to agree with that of the Y ( 4220 ).
Using a total of 9.0 fb−1 of e+e− collision data with center-of-mass energies between 4.15 and 4.30 GeV collected by the BESIII detector, we search for the processes e+e−→γX(3872) with X(3872)→π0χcJ ...for J=0, 1, 2. We report the first observation of X(3872)→π0χc1, a new decay mode of the X(3872), with a statistical significance of more than 5σ for all systematic fit variations. Normalizing to the previously established process e+e−→γX(3872) with X(3872)→π+π−J/ψ, we find B(X(3872)→π0χc1)/B(X(3872)→π+π−J/ψ)=0.88−0.27+0.33±0.10, where the first error is statistical and the second is systematic. We set 90% confidence level upper limits on the corresponding ratios for the decays to π0χc0 and π0χc2 of 19 and 1.1, respectively.
Follow-up studies on auricular reconstruction procedures have reported postoperative complications; some of which can only be reversed with revision surgery. This study aims to provide a feasible ...surgical strategy based on the Nagata method for patients requiring secondary revision and verify mid-term aesthetic outcomes.
Secondary auricular reconstructions based on the Nagata method were performed on seven patients seeking secondary revision between 2017 and 2021. Scores of a five-point Likert scale and artificial intelligence ratings based on convolutional nerve networks were used as outcome measures.
Five patients underwent complete two-stage ear reconstruction, and the other two patients underwent the first-stage microtia procedure only. Few complications were observed, except in Case 4; this patient required an additional minor surgery after frame exposure 6 weeks after the first-stage procedure. All revised ears showed clear anatomical structures, and all patients were satisfied with the aesthetic results. Statistical analysis showed a significant increase in postoperative versus preoperative scores by convolutional neural network models (p < 0.05). Cases 5 and 6, which involved projection surgeries only, had decreased artificial intelligence appearance scores postoperatively.
After adequate preoperative evaluation, secondary auricle reconstruction based on the Nagata method can achieve reliable aesthetic outcomes with few complications.
ClinicalTrials.gov ID: NCT05604456.
By analyzing a data sample corresponding to an integrated luminosity of 2.93 fb−1 collected at a center-of-mass energy of 3.773 GeV with the BESIII detector, we measure for the first time the ...absolute branching fraction of the D+ → ημ+νμ decay to be BD+→ημ+νμ = ( 10.4 ± 1.0stat ± 0.5syst) × 10−4. Using the world averaged value of BD+ → ηe+νe, the ratio of the two branching fractions is determined to be BD+ → ημ+νμ/BD+ → ηe+νe = 0.91 ± 0.13(stat+syst), which agrees with the theoretical expectation of lepton flavor universality within uncertainty. By studying the differential decay rates in five four-momentum transfer intervals, we obtain the product of the hadronic form factor f+η(0) and the c → d Cabibbo-Kobayashi-Maskawa matrix element |Vcd| to be fη+(0) |Vcd| = 0.087 ± 0.008stat ± 0.002syst. Taking the input of |Vcd| from the global fit in the standard model, we determine fη+(0) = 0.39 ± 0.04stat ± 0.01syst. On the other hand, using the value of fη+(0) calculated in theory, we find |Vcd| = 0.242 ± 0.022stat ± 0.00 6 syst ± 0.033theory.
Using a data sample corresponding to an integrated luminosity of 2.93 fb−1 recorded by the BESIII detector at a center-of-mass energy of 3.773 GeV, we present an analysis of the decays D0 → π−π0e+νe ...and D+ → π−π+e+νe. By performing a partial wave analysis, the π+π− S-wave contribution to D+ → π−π+e+νe is observed to be (25.7 ± 1.6 ± 1.1)% with a statistical significance greater than 10σ, besides the dominant P-wave contribution. This is the first observation of the S-wave contribution. We measure the branching fractions B(D0 → ρ−e+νe) = (1.445 ± 0.058 ± 0.039) × 10−3, B(D+ → ρ0e+νe) = (1.860 ± 0.070 ± 0.061) × 10−3, and B(D+ → f0(500)e+νe, f0(500) → π+π−) = (6.30 ± 0.43 ± 0.32) × 10−4. An upper limit of B(D+ → f0(980)e+νe, f0(980) → π+π−) < 2.8 × 10−5 is set at the 90% confidence level. We also obtain the hadronic form factor ratios of D → ρe+νe at q2 = 0 assuming the single-pole dominance parametrization: rV = {V(0)/A1(0)} = 1.695 ± 0.083 ± 0.051, r2 = {A2(0)/A1(0)} = 0.845 ± 0.056 ± 0.039.
We report the first observation of D+→τ+ντ with a significance of 5.1σ. We measure B(D+→τ+ντ)=(1.20±0.24stat±0.12syst)×10−3. Taking the world average B(D+→μ+νμ)=(3.74±0.17)×10−4, we obtain ...Rτ/μ=Γ(D+→τ+ντ)/Γ(D+→μ+νμ)=3.21±0.64stat±0.43syst., which is consistent with the standard model expectation of lepton flavor universality. Using external inputs, our results give values for the D+ decay constant fD+ and the Cabibbo-Kobayashi-Maskawa matrix element |Vcd| that are consistent with, but less precise than, other determinations.
Using e+e− annihilation data corresponding to an integrated luminosity of 3.19 fb−1 collected at a center-of-mass energy of 4.178 GeV with the BESIII detector, we measure the absolute branching ...fractions BDs+→ηe+νe = (2.323±0.063stat ± 0.063syst)% and BDs+→η′e+νe = (0.824±0.073stat ± 0.027syst)% via a tagged analysis technique, where one Ds is fully reconstructed in a hadronic mode. Combining these measurements with previous BESIII measurements of BD+→η(′)e+νe, the η−η′ mixing angle in the quark flavor basis is determined to be ϕP = (40.1±2.1stat ± 0.7syst)°. From the first measurements of the dynamics of Ds+ → η(′)e+νe decays, the products of the hadronic form factors f+η(′)(0) and the Cabibbo-Kobayashi-Maskawa matrix element |Vcs| are determined with different form factor parametrizations. For the two-parameter series expansion, the results are f+η(0)|Vcs| = 0.4455±0.0053stat±0.0044syst and f+η′(0)|Vcs|=0.477±0.049stat±0.011syst.
Using an e+e− collision data sample of 2.93 fb−1 collected at a center-of-mass energy of 3.773 GeV by the BESIII detector at BEPCII, we report the observation of D0→a0(980)−e+νe and evidence for ...D+→a0(980)0e+νe with significances of 6.4σ and 2.9σ, respectively. The absolute branching fractions are determined to be B(D0→a0(980)−e+νe)×B(a0(980)−→ηπ−)=1.33−0.29+0.33(stat)±0.09(syst)×10−4 and B(D+→a0(980)0e+νe)×B(a0(980)0→ηπ0)=1.66−0.66+0.81(stat)±0.11(syst)×10−4. This is the first time the a0(980) meson has been measured in a D0 semileptonic decay, which would open one more interesting page in the investigation of the nature of the puzzling a0(980) states.
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