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2.
Eur Heart J Case Rep ; 8(10): ytae547, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39439782

RESUMO

Background: Coarctation of the aorta (CoA) is a common congenital heart defect that affects about 3-4 in every 10 000 live births. Despite clear signs on clinical examination, the diagnosis is sometimes not made until adulthood. An increasing number of patients with CoA are reaching child-bearing age. Unrepaired CoA or severe recurrent stenosis during pregnancy is a significant concern, as it poses a high risk of maternal and foetal complications and even death. Case summary: A 21-year-old woman was referred to the cardiology department at 17 weeks' gestation for management of arterial hypertension and unexplained systolic murmur. She had been diagnosed with hypertension elsewhere the year before presentation, but unfortunately, this remained unexplored. She had been started on labetalol early in the pregnancy. Clinical examination showed a loud systolic heart murmur extending from parasternal to subclavicular and scapular areas. Pulses in the lower extremities were very weak, and blood pressure was slightly elevated with a significant gradient between the upper and lower extremities. Echocardiography showed remarkable absence of pulsatile flow in the abdominal aorta and narrowing just distal to the subclavian artery with typical diastolic tail pattern on suprasternal imaging. Cardiac magnetic resonance confirmed the presence of a severe coarctation distal to the subclavian artery and presence of multiple collaterals allocating this patient in the extremely high-risk category with a risk of up to 40%-100% of maternal cardiac event during pregnancy. An extensive multidisciplinary team meeting was convened. After initial medical optimization, increased claudication and signs of placental hypoperfusion necessitated an endovascular procedure under general anaesthesia at 23 weeks' gestation. A Bentley BeGraft Plus stent (16 × 38 mm) was successfully placed. Postoperative ultrasound showed biphasic placental perfusion and normalization of blood pressure and ankle-brachial indices. At 36 weeks' gestation, the patient gave birth to a healthy child. Discussion: Coarctation of the aorta should be considered in any young patient with arterial hypertension. Altered maternal haemodynamics during pregnancy resulted in severe symptomatic CoA and reduced placental flow necessitating percutaneous intervention during pregnancy. A multidisciplinary pregnancy heart team is essential for optimal treatment management in these high-risk patients.

3.
Zhonghua Yi Xue Za Zhi ; 104(39): 3661-3668, 2024 Oct 22.
Artigo em Chinês | MEDLINE | ID: mdl-39428215

RESUMO

Objective: To compare the postoperative analgesic efficacy of ultrasound-guided infraspinatus-teres minor interfascial block and interscalene block in shoulder arthroscopic surgery. Methods: A total of 74 patients undergoing shoulder arthroscopic surgery at the Affiliated Hospital of Jiaxing University from December 2023 to February 2024 were prospectively included, whose age ranged from 18 to 80 years and the American Society of Anesthesiologists (ASA) grade were Ⅰ-Ⅲ. Patients were divided into two groups using block randomization: infraspinatus-teres minor interfascial block group (observation group) and interscalene block group (control group), with 37 cases in each group. In the anesthesia preparation room, all patients received nerve blocks under ultrasound guidance with 20 ml of 0.375% ropivacaine. Patient-controlled intravenous analgesia (PCIA) was administered to all patients following surgery. The primary outcome was the area under the curve (AUC) of the numeric rating scale (NRS) for pain within 24 hours postoperatively. Secondary outcome measures included the highest NRS score within 48 hours postoperatively, the amount of sufentanil used via PCIA within 48 hours postoperatively, the incidence of rescue analgesia and rebound pain, QoR-40 scores, and the rate of postoperative nausea and vomiting within 24 hours. The non-inferiority margin for the AUC of NRS scores between the two types of regional nerve blocks was set at "2.6". Results: A total of 35 patients were included in the observation group [17 males, 18 females, aged (58.1±9.1) years], and 36 patients were included in the control group [12 males, 24 females, aged (57.0±9.8) years]. The AUC of the NRS scores at rest within 24 hours post-operation was 51.7±10.9 in the observation group and 62.6±13.6 in the control group. The difference in AUC between the two groups was -10.9 (95%CI:-16.8--5.1), with the upper limit of the 95%CI falling below the predefined non-inferiority margin of "2.6" (non-inferiority P<0.001). The highest NRS score [M (Q1, Q3)] within 48 hours post-surgery was 3 (3, 4) in the control group, which was significantly higher than the observation group's score of 2 (2, 3) (P<0.001). During the postoperative period of 0-12 hours, the observation group received a median dose of 12 (10, 14) µg of sufentanil, which was significantly higher than the control group's dose of 8 (6, 10) µg (P<0.001). During the postoperative period of 12-24 hours, the observation group received a median dose of 8 (8, 10) µg of sufentanil, which was significantly lower than the control group's median dose of 12 (10, 14) µg (P<0.001). During the postoperative period of 24-48 hours, there was no statistically significant difference in the dose of sufentanil between the two groups of patients (P=0.548). In the observation group, the incidence of rescue analgesia within 48 hours postoperatively was 0 (0/35), which was lower than that of the control group at 22.2% (8/36) (P=0.010). The occurrence of rebound pain in the observation group was 0 (0/35), and the control group was 11.1% (4/36), no statistically significant difference was found between two groups (P=0.130). In the observation group, the QoR-40 score within 24 hours post-operation was 180.2±3.2, which was higher than the control group's score of 175.8±4.7 (P<0.001). There was no statistically significant difference in the incidence of postoperative nausea and vomiting within 24 hours between the two groups (P=0.372). Conclusion: Ultrasound-guided infraspinatus-teres minor interfascial block demonstrates a comparable analgesic effect to interscalene block in shoulder arthroscopic surgery within the first 24 hours postoperatively.


Assuntos
Artroscopia , Bloqueio do Plexo Braquial , Bloqueio Nervoso , Dor Pós-Operatória , Humanos , Bloqueio Nervoso/métodos , Dor Pós-Operatória/prevenção & controle , Adulto , Pessoa de Meia-Idade , Bloqueio do Plexo Braquial/métodos , Estudos Prospectivos , Ropivacaina/administração & dosagem , Ultrassonografia de Intervenção , Idoso , Ombro/cirurgia , Masculino , Medição da Dor , Feminino , Plexo Braquial , Adolescente , Anestésicos Locais/administração & dosagem
4.
Phys Rev Lett ; 133(8): 081901, 2024 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-39241714

RESUMO

Using data samples collected with the BESIII detector at the BEPCII collider at center-of-mass energies ranging from 3.80 to 4.95 GeV, corresponding to an integrated luminosity of 20 fb^{-1}, a measurement of Born cross sections for the e^{+}e^{-}→D^{0}D[over ¯]^{0} and D^{+}D^{-} processes is presented with unprecedented precision. Many clear peaks in the line shape of e^{+}e^{-}→D^{0}D[over ¯]^{0} and D^{+}D^{-} around the mass range of G(3900), ψ(4040), ψ(4160), Y(4260), and ψ(4415), etc., are foreseen. These results offer crucial experimental insights into the nature of hadron production in the open-charm region.

5.
Phys Rev Lett ; 132(18): 181901, 2024 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-38759175

RESUMO

Based on (10087±44)×10^{6} J/ψ events collected with the BESIII detector, a partial wave analysis of the decay J/ψ→γK_{S}^{0}K_{S}^{0}η^{'} is performed. The mass and width of the X(2370) are measured to be 2395±11(stat)_{-94}^{+26}(syst) MeV/c^{2} and 188_{-17}^{+18}(stat)_{-33}^{+124}(syst) MeV, respectively. The corresponding product branching fraction is B[J/ψ→γX(2370)]×B[X(2370)→f_{0}(980)η^{'}]×B[f_{0}(980)→K_{S}^{0}K_{S}^{0}]=(1.31±0.22(stat)_{-0.84}^{+2.85}(syst))×10^{-5}. The statistical significance of the X(2370) is greater than 11.7σ and the spin parity is determined to be 0^{-+} for the first time. The measured mass and spin parity of the X(2370) are consistent with the predictions of the lightest pseudoscalar glueball.

6.
Phys Rev Lett ; 132(19): 191902, 2024 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-38804946

RESUMO

We report the measurement of the inclusive cross sections for e^{+}e^{-}→nOCH (where nOCH denotes non-open charm hadrons) with improved precision at center-of-mass (c.m.) energies from 3.645 to 3.871 GeV. We observe three resonances: R(3760), R(3780), and R(3810) with significances of 8.1σ, 13.7σ, and 8.8σ, respectively. The R(3810) state is observed for the first time, while the R(3760) and R(3780) states are observed for the first time in the nOCH cross sections. Two sets of resonance parameters describe the energy-dependent line shape of the cross sections well. In set I [set II], the R(3810) state has mass (3805.7±1.1±2.7) [(3805.7±1.1±2.7)] MeV/c^{2}, total width (11.6±2.9±1.9) [(11.5±2.8±1.9)] MeV, and an electronic width multiplied by the nOCH decay branching fraction of (10.9±3.8±2.5) [(11.0±3.4±2.5)] eV. In addition, we measure the branching fractions B[R(3760)→nOCH]=(25.2±16.1±30.4)%[(6.4±4.8±7.7)%] and B[R(3780)→nOCH]=(12.3±6.6±8.3)%[(10.4±4.8±7.0)%] for the first time. The R(3760) state can be interpreted as an open-charm (OC) molecular state, but containing a simple four-quark state component. The R(3810) state can be interpreted as a hadrocharmonium state.

7.
Phys Rev Lett ; 132(16): 161901, 2024 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-38701481

RESUMO

We present measurements of the Born cross sections for the processes e^{+}e^{-}→ωχ_{c1} and ωχ_{c2} at center-of-mass energies sqrt[s] from 4.308 to 4.951 GeV. The measurements are performed with data samples corresponding to an integrated luminosity of 11.0 fb^{-1} collected with the BESIII detector operating at the Beijing Electron Positron Collider storage ring. Assuming the e^{+}e^{-}→ωχ_{c2} signals come from a single resonance, the mass and width are determined to be M=(4413.6±9.0±0.8) MeV/c^{2} and Γ=(110.5±15.0±2.9) MeV, respectively, which is consistent with the parameters of the well-established resonance ψ(4415). In addition, we also use one single resonance to describe the e^{+}e^{-}→ωχ_{c1} line shape and determine the mass and width to be M=(4544.2±18.7±1.7) MeV/c^{2} and Γ=(116.1±33.5±1.7) MeV, respectively. The structure of this line shape, observed for the first time, requires further understanding.

8.
Phys Rev Lett ; 132(14): 141901, 2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38640399

RESUMO

Using e^{+}e^{-} collision data corresponding to an integrated luminosity of 7.33 fb^{-1} recorded by the BESIII detector at center-of-mass energies between 4.128 and 4.226 GeV, we present an analysis of the decay D_{s}^{+}→π^{+}π^{-}e^{+}ν_{e}, where the D_{s}^{+} is produced via the process e^{+}e^{-}→D_{s}^{*±}D_{s}^{∓}. We observe the f_{0}(980) in the π^{+}π^{-} system and the branching fraction of the decay D_{s}^{+}→f_{0}(980)e^{+}ν_{e} with f_{0}(980)→π^{+}π^{-} measured to be (1.72±0.13_{stat}±0.10_{syst})×10^{-3}, where the uncertainties are statistical and systematic, respectively. The dynamics of the D_{s}^{+}→f_{0}(980)e^{+}ν_{e} decay are studied with the simple pole parametrization of the hadronic form factor and the Flatté formula describing the f_{0}(980) in the differential decay rate, and the product of the form factor f_{+}^{f_{0}}(0) and the c→s Cabibbo-Kobayashi-Maskawa matrix element |V_{cs}| is determined for the first time to be f_{+}^{f_{0}}(0)|V_{cs}|=0.504±0.017_{stat}±0.035_{syst}. Furthermore, the decay D_{s}^{+}→f_{0}(500)e^{+}ν_{e} is searched for the first time but no signal is found. The upper limit on the branching fraction of D_{s}^{+}→f_{0}(500)e^{+}ν_{e}, f_{0}(500)→π^{+}π^{-} decay is set to be 3.3×10^{-4} at 90% confidence level.

9.
Phys Rev Lett ; 132(15): 151903, 2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38682963

RESUMO

We perform a study of the χ_{c1}(3872) line shape using the data samples of e^{+}e^{-}→γχ_{c1}(3872), χ_{c1}(3872)→D^{0}D[over ¯]^{0}π^{0}, and π^{+}π^{-}J/ψ collected with the BESIII detector. The effects of the coupled channels and the off-shell D^{*0} are included in the parametrization of the line shape. The line shape mass parameter is obtained to be M_{X}=(3871.63±0.13_{-0.05}^{+0.06}) MeV. Two poles are found on the first and second Riemann sheets corresponding to the D^{*0}D[over ¯]^{0} branch cut. The pole location on the first sheet is much closer to the D^{*0}D[over ¯]^{0} threshold than the other, and is determined to be 7.04±0.15_{-0.08}^{+0.07} MeV above the D^{0}D[over ¯]^{0}π^{0} threshold with an imaginary part -0.19±0.08_{-0.19}^{+0.14} MeV.

10.
Phys Rev Lett ; 132(15): 151901, 2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38682972

RESUMO

Using a sample of (10087±44)×10^{6} J/ψ events, which is about 45 times larger than that was previously analyzed, a further investigation on the J/ψ→γ3(π^{+}π^{-}) decay is performed. A significant distortion at 1.84 GeV/c^{2} in the line shape of the 3(π^{+}π^{-}) invariant mass spectrum is observed for the first time, which could be resolved by two overlapping resonant structures, X(1840) and X(1880). The new state X(1880) is observed with a statistical significance larger than 10σ. The mass and width of X(1880) are determined to be 1882.1±1.7±0.7 MeV/c^{2} and 30.7±5.5±2.4 MeV, respectively, which indicates the existence of a pp[over ¯] bound state.

11.
Phys Rev Lett ; 132(13): 131901, 2024 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-38613263

RESUMO

We present cross sections for the reaction e^{+}e^{-}→K_{S}^{0}K_{L}^{0} at center-of-mass energies ranging from 3.51 to 4.95 GeV using data samples collected in the BESIII experiment, corresponding to a total integrated luminosity of 26.5 fb^{-1}. The ratio of neutral-to-charged kaon form factors at large momentum transfers (12

12.
Phys Rev Lett ; 132(13): 131903, 2024 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-38613307

RESUMO

We perform for the first time an amplitude analysis of the decay D^{+}→K_{S}^{0}π^{+}η and report the observation of the decay D^{+}→K_{S}^{0}a_{0}(980)^{+} using 2.93 fb^{-1} of e^{+}e^{-} collision data taken at a center-of-mass energy of 3.773 GeV with the BESIII detector. As the only W-annihilation-free decay among D to a_{0}(980) pseudoscalar, D^{+}→K_{S}^{0}a_{0}(980)^{+} is the ideal decay in extracting the contributions of the W-emission amplitudes involving a_{0}(980) and to study the final-state interactions. The absolute branching fraction of D^{+}→K_{S}^{0}π^{+}η is measured to be (1.27±0.04_{stat}±0.03_{syst})%. The branching fractions of intermediate processes D^{+}→K_{S}^{0}a_{0}(980)^{+} with a_{0}(980)^{+}→π^{+}η and D^{+}→π^{+}K[over ¯]_{0}^{*}(1430)^{0} with K[over ¯]_{0}^{*}(1430)^{0}→K_{S}^{0}η are measured to be (1.33±0.05_{stat}±0.04_{syst})% and (0.14±0.03_{stat}±0.01_{syst})%, respectively.

13.
Phys Rev Lett ; 132(8): 081904, 2024 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-38457707

RESUMO

Based on data samples collected with the BESIII detector at the BEPCII collider, the process e^{+}e^{-}→Σ^{+}Σ[over ¯]^{-} is studied at center-of-mass energies sqrt[s]=2.3960, 2.6454, and 2.9000 GeV. Using a fully differential angular description of the final state particles, both the relative magnitude and phase information of the Σ^{+} electromagnetic form factors in the timelike region are extracted. The relative phase between the electric and magnetic form factors is determined to be sinΔΦ=-0.67±0.29(stat)±0.18(syst) at sqrt[s]=2.3960 GeV, ΔΦ=55°±19°(stat)±14°(syst) at sqrt[s]=2.6454 GeV, and 78°±22°(stat)±9°(syst) at sqrt[s]=2.9000 GeV. For the first time, the phase of the hyperon electromagnetic form factors is explored in a wide range of four-momentum transfer. The evolution of the phase along with four-momentum transfer is an important input for understanding its asymptotic behavior and the dynamics of baryons.

14.
Phys Rev Lett ; 132(10): 101801, 2024 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-38518329

RESUMO

Using (10087±44)×10^{6} J/ψ events collected with the BESIII detector, numerous Ξ^{-} and Λ decay asymmetry parameters are simultaneously determined from the process J/ψ→Ξ^{-}Ξ[over ¯]^{+}→Λ(pπ^{-})π^{-}Λ[over ¯](n[over ¯]π^{0})π^{+} and its charge-conjugate channel. The precisions of α_{Λ0} for Λ→nπ^{0} and α[over ¯]_{Λ0} for Λ[over ¯]→n[over ¯]π^{0} compared to world averages are improved by factors of 4 and 1.7, respectively. The ratio of decay asymmetry parameters of Λ→nπ^{0} to that of Λ→pπ^{-}, ⟨α_{Λ0}⟩/⟨α_{Λ-}⟩, is determined to be 0.873±0.012_{-0.010}^{+0.011}, where the first and the second uncertainties are statistical and systematic, respectively. The ratio is smaller than unity more than 5σ, which signifies the existence of the ΔI=3/2 transition in Λ for the first time. Besides, we test for CP symmetry in Ξ^{-}→Λπ^{-} and in Λ→nπ^{0} with the best precision to date.

15.
Phys Rev Lett ; 132(9): 091802, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38489649

RESUMO

By analyzing 7.33 fb^{-1} of e^{+}e^{-} annihilation data collected at center-of-mass energies between 4.128 and 4.226 GeV with the BESIII detector, we report the observation of the semileptonic decay D_{s}^{+}→η^{'}µ^{+}ν_{µ}, with a statistical significance larger than 10σ, and the measurements of the D_{s}^{+}→ηµ^{+}ν_{µ} and D_{s}^{+}→η^{'}µ^{+}ν_{µ} decay dynamics for the first time. The branching fractions of D_{s}^{+}→ηµ^{+}ν_{µ} and D_{s}^{+}→η^{'}µ^{+}ν_{µ} are determined to be (2.235±0.051_{stat}±0.052_{syst})% and (0.801±0.055_{stat}±0.028_{syst})%, respectively, with precision improved by factors of 6.0 and 6.6 compared to the previous best measurements. Combined with the results for the decays D_{s}^{+}→ηe^{+}ν_{e} and D_{s}^{+}→η^{'}e^{+}ν_{e}, the ratios of the decay widths are examined both inclusively and in several ℓ^{+}ν_{ℓ} four-momentum transfer ranges. No evidence for lepton flavor universality violation is found within the current statistics. The products of the hadronic form factors f_{+,0}^{η^{(')}}(0) and the c→s Cabibbo-Kobayashi-Maskawa matrix element |V_{cs}| are determined. The results based on the two-parameter series expansion are f_{+,0}^{η}(0)|V_{cs}|=0.452±0.010_{stat}±0.007_{syst} and f_{+,0}^{η^{'}}(0)|V_{cs}|=0.504±0.037_{stat}±0.012_{syst}, which help to constrain present models on f_{+,0}^{η^{(')}}(0). The forward-backward asymmetries are determined to be ⟨A_{FB}^{η}⟩=-0.059±0.031_{stat}±0.005_{syst} and ⟨A_{FB}^{η^{'}}⟩=-0.064±0.079_{stat}±0.006_{syst} for the first time, which are consistent with the theoretical calculation.

16.
Phys Rev Lett ; 132(3): 031801, 2024 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-38307076

RESUMO

Based on 4.4 fb^{-1} of e^{+}e^{-} annihilation data collected at the center-of-mass energies between 4.60 and 4.70 GeV with the BESIII detector at the BEPCII collider, the pure W-boson-exchange decay Λ_{c}^{+}→Ξ^{0}K^{+} is studied with a full angular analysis. The corresponding decay asymmetry is measured for the first time to be α_{Ξ^{0}K^{+}}=0.01±0.16(stat)±0.03(syst). This result reflects the noninterference effect between the S- and P-wave amplitudes. The phase shift between S- and P-wave amplitudes has two solutions, which are δ_{p}-δ_{s}=-1.55±0.25(stat)±0.05(syst) rad or 1.59±0.25(stat)±0.05(syst) rad.

17.
Phys Rev Lett ; 131(19): 191901, 2023 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-38000396

RESUMO

We study the process e^{+}e^{-}→Λ_{c}^{+}Λ[over ¯]_{c}^{-} at twelve center-of-mass energies from 4.6119 to 4.9509 GeV using data samples collected by the BESIII detector at the BEPCII collider. The Born cross sections and effective form factors (|G_{eff}|) are determined with unprecedented precision after combining the single and double-tag methods based on the decay process Λ_{c}^{+}→pK^{-}π^{+}. Flat cross sections around 4.63 GeV are obtained and no indication of the resonant structure Y(4630), as reported by Belle, is found. In addition, no oscillatory behavior is discerned in the |G_{eff}| energy dependence of Λ_{c}^{+}, in contrast to what is seen for the proton and neutron cases. Analyzing the cross section together with the polar-angle distribution of the Λ_{c}^{+} baryon at each energy point, the moduli of electric and magnetic form factors (|G_{E}| and |G_{M}|) are extracted and separated. For the first time, the energy dependence of the form factor ratio |G_{E}/G_{M}| is observed, which can be well described by an oscillatory function.

18.
Phys Rev Lett ; 131(19): 191802, 2023 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-38000397

RESUMO

The quantum entangled J/ψ→Σ^{+}Σ[over ¯]^{-} pairs from (1.0087±0.0044)×10^{10} J/ψ events taken by the BESIII detector are used to study the nonleptonic two-body weak decays Σ^{+}→nπ^{+} and Σ[over ¯]^{-}→n[over ¯]π^{-}. The CP-odd weak decay parameters of the decays Σ^{+}→nπ^{+} (α_{+}) and Σ[over ¯]^{-}→n[over ¯]π^{-} (α[over ¯]_{-}) are determined to be 0.0481±0.0031_{stat}±0.0019_{syst} and -0.0565±0.0047_{stat}±0.0022_{syst}, respectively. The decay parameter α[over ¯]_{-} is measured for the first time, and the accuracy of α_{+} is improved by a factor of 4 compared to the previous results. The simultaneously determined decay parameters allow the first precision CP symmetry test for any hyperon decay with a neutron in the final state with the measurement of A_{CP}=(α_{+}+α[over ¯]_{-})/(α_{+}-α[over ¯]_{-})=-0.080±0.052_{stat}±0.028_{syst}. Assuming CP conservation, the average decay parameter is determined as ⟨α_{+}⟩=(α_{+}-α[over ¯]_{-})/2=-0.0506±0.0026_{stat}±0.0019_{syst}, while the ratios α_{+}/α_{0} and α[over ¯]_{-}/α[over ¯]_{0} are -0.0490±0.0032_{stat}±0.0021_{syst} and -0.0571±0.0053_{stat}±0.0032_{syst}, where α_{0} and α[over ¯]_{0} are the decay parameters of the decays Σ^{+}→pπ^{0} and Σ[over ¯]^{-}→p[over ¯]π^{0}, respectively.

19.
Phys Rev Lett ; 131(14): 141802, 2023 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-37862669

RESUMO

Using 7.33 fb^{-1} of e^{+}e^{-} collision data taken with the BESIII detector at the BEPCII collider, we report the first experimental study of the purely leptonic decay D_{s}^{*+}→e^{+}ν_{e}. Our data contain a signal of this decay with a statistical significance of 2.9σ. The branching fraction of D_{s}^{*+}→e^{+}ν_{e} is measured to be (2.1_{-0.9_{stat}}^{+1.2}±0.2_{syst})×10^{-5}, corresponding to an upper limit of 4.0×10^{-5} at the 90% confidence level. Taking the total width of the D_{s}^{*+} [(0.070±0.028) keV] predicted with the radiative D_{s}^{*+} decay from the lattice QCD calculation as input, the decay constant of the D_{s}^{*+} is determined to be f_{D_{s}^{*+}}=(214_{-46_{stat}}^{+61}±44_{syst}) MeV, corresponding to an upper limit of 354 MeV at the 90% confidence level.

20.
Phys Rev Lett ; 131(15): 151901, 2023 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-37897776

RESUMO

A narrow structure in the pΛ[over ¯] system near the mass threshold, named as X(2085), is observed in the process e^{+}e^{-}→pK^{-}Λ[over ¯] with a statistical significance greater than 20σ. Its spin and parity are determined for the first time to be J^{P}=1^{+} in an amplitude analysis, with a statistical significance greater than 5σ over other quantum numbers (0^{-},1^{-} and 2^{+}). The pole positions of X(2085) are measured to be M_{pole}=(2084_{-2}^{+4}±9) MeV and Γ_{pole}=(58_{-3}^{+4}±25) MeV, where the first uncertainties are statistical and the second ones are systematic. The analysis is based on the study of the process e^{+}e^{-}→pK^{-}Λ[over ¯] and uses the data samples collected with the BESIII detector at the center-of-mass energies sqrt[s]=4.008, 4.178, 4.226, 4.258, 4.416, and 4.682 GeV with a total integrated luminosity of 8.35 fb^{-1}.

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