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1.
Phys Rev Lett ; 127(17): 171801, 2021 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-34739288

RESUMO

Using a dataset of 6.32 fb^{-1} of e^{+}e^{-} annihilation data collected with the BESIII detector at center-of-mass energies between 4178 and 4226 MeV, we have measured the absolute branching fraction of the leptonic decay D_{s}^{+}→τ^{+}ν_{τ} via τ^{+}→e^{+}ν_{e}ν[over ¯]_{τ}, and find B_{D_{s}^{+}→τ^{+}ν_{τ}}=(5.27±0.10±0.12)×10^{-2}, where the first uncertainty is statistical and the second is systematic. The precision is improved by a factor of 2 compared to the previous best measurement. Combining with f_{D_{s}^{+}} from lattice quantum chromodynamics calculations or the |V_{cs}| from the CKMfitter group, we extract |V_{cs}|=0.978±0.009±0.012 and f_{D_{s}^{+}}=(251.1±2.4±3.0) MeV, respectively. Combining our result with the world averages of B_{D_{s}^{+}→τ^{+}ν_{τ}} and B_{D_{s}^{+}→µ^{+}ν_{µ}}, we obtain the ratio of the branching fractions B_{D_{s}^{+}→τ^{+}ν_{τ}}/B_{D_{s}^{+}→µ^{+}ν_{µ}}=9.72±0.37, which is consistent with the standard model prediction of lepton flavor universality.

2.
Phys Rev Lett ; 127(13): 131801, 2021 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-34623854

RESUMO

Using 2.93 fb^{-1} of e^{+}e^{-} collision data taken with the BESIII detector at a center-of-mass energy of 3.773 GeV, the observation of the D^{0}→K_{1}(1270)^{-}e^{+}ν_{e} semileptonic decay is presented. The statistical significance of the decay D^{0}→K_{1}(1270)^{-}e^{+}ν_{e} is greater than 10σ. The branching fraction of D^{0}→K_{1}(1270)^{-}e^{+}ν_{e} is measured to be (1.09±0.13_{-0.16}^{+0.09}±0.12)×10^{-3}. Here, the first uncertainty is statistical, the second is systematic, and the third originates from the assumed branching fraction of K_{1}(1270)^{-}→K^{-}π^{+}π^{-}. The fraction of longitudinal polarization in D^{0}→K_{1}(1270)^{-}e^{+}ν_{e} is determined for the first time to be 0.50±0.19_{stat}±0.08_{syst}.

3.
Phys Rev Lett ; 127(12): 121802, 2021 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-34597097

RESUMO

The absolute branching fraction of Λ→pµ^{-}ν[over ¯]_{µ} is reported for the first time based on an e^{+}e^{-} annihilation sample of 10×10^{9} J/ψ events collected with the BESIII detector at sqrt[s]=3.097 GeV. The branching fraction is determined to be B(Λ→pµ^{-}ν[over ¯]_{µ})=[1.48±0.21(stat)±0.08(syst)]×10^{-4}, which is improved by about 30% in precision over the previous indirect measurements. Combining this result with the world average of B(Λ→pe^{-}ν[over ¯]_{e}), we obtain the ratio {[Γ(Λ→pµ^{-}ν[over ¯]_{µ})]/[Γ(Λ→pe^{-}ν[over ¯]_{e})]} to be 0.178±0.028, which agrees with the standard model prediction assuming lepton flavor universality. The asymmetry of the branching fractions of Λ→pµ^{-}ν[over ¯]_{µ} and Λ[over ¯]→p[over ¯]µ^{+}ν_{µ} is also determined, and no evidence for CP violation is found.

4.
Phys Rev Lett ; 127(8): 082002, 2021 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-34477419

RESUMO

We report a measurement of the observed cross sections of e^{+}e^{-}→J/ψX based on 3.21 fb^{-1} of data accumulated at energies from 3.645 to 3.891 GeV with the BESIII detector operated at the BEPCII collider. In analysis of the cross sections, we measured the decay branching fractions of B(ψ(3686)→J/ψX)=(64.4±0.6±1.6)% and B(ψ(3770)→J/ψX)=(0.5±0.2±0.1)% for the first time. The energy-dependent line shape of these cross sections cannot be well described by two Breit-Wigner (BW) amplitudes of the expected decays ψ(3686)→J/ψX and ψ(3770)→J/ψX. Instead, it can be better described with one more BW amplitude of the decay R(3760)→J/ψX. Under this assumption, we extracted the R(3760) mass M_{R(3760)}=3766.2±3.8±0.4 MeV/c^{2} , total width Γ_{R(3760)}^{tot}=22.2±5.9±1.4 MeV, and product of leptonic width and decay branching fraction Γ_{R(3760)}^{ee}B[R(3760)→J/ψX]=(79.4±85.5±11.7) eV. The significance of the R(3760) is 5.3σ. The first uncertainties of these measured quantities are from fits to the cross sections and second systematic.

5.
Rev Sci Instrum ; 92(5): 053508, 2021 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-34243260

RESUMO

Optimized operation of fusion devices demands detailed understanding of plasma transport, a problem that must be addressed with advances in both measurement and data analysis techniques. In this work, we adopt Bayesian inference methods to determine experimental particle transport, leveraging opportunities from high-resolution He-like ion spectra in a tokamak plasma. The Bayesian spectral fitting code is used to analyze resonance (w), forbidden (z), intercombination (x, y), and satellite (k, j) lines of He-like Ca following laser blow-off injections on Alcator C-Mod. This offers powerful transport constraints since these lines depend differently on electron temperature and density, but also differ in their relation to Li-like, He-like, and H-like ion densities, often the dominant Ca charge states over most of the C-Mod plasma radius. Using synthetic diagnostics based on the AURORA package, we demonstrate improved effectiveness of impurity transport inferences when spectroscopic data from a progressively larger number of lines are included.

7.
Phys Rev Lett ; 126(9): 092002, 2021 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-33750166

RESUMO

We present an analysis of the process ψ(3686)→Ω^{-}Ω[over ¯]^{+} (Ω^{-}→K^{-}Λ, Ω[over ¯]^{+}→K^{+}Λ[over ¯], Λ→pπ^{-}, Λ[over ¯]→p[over ¯]π^{+}) based on a dataset of 448×10^{6} ψ(3686) decays collected with the BESIII detector at the BEPCII electron-positron collider. The helicity amplitudes for the process ψ(3686)→Ω^{-}Ω[over ¯]^{+} and the decay parameters of the subsequent decay Ω^{-}→K^{-}Λ (Ω[over ¯]^{+}→K^{+}Λ[over ¯]) are measured for the first time by a fit to the angular distribution of the complete decay chain, and the spin of the Ω^{-} is determined to be 3/2 for the first time since its discovery more than 50 years ago.

8.
Fa Yi Xue Za Zhi ; 37(1): 77-80, 2021 Feb.
Artigo em Inglês, Chinês | MEDLINE | ID: mdl-33780189

RESUMO

Abstract: Death after carotid sinus trauma is usually attributed to death from inhibition, a type of sudden death. Currently, the number of incidents is scarce, and related studies are few. Therefore, how to determine the involvement of carotid sinus and determine the role of diseases in the cause of death has always been a difficult point in forensic investigation. This article sorts out the research literature on carotid sinus related death at home and abroad in recent years, systematically reviews the anatomic structure of the carotid sinus nerve, the clinical epidemiology of carotid sinus syndrome, and the research on the death mechanism of carotid sinus injury at home and abroad in recent years, in order to provide references for forensic pathology research and prosecution.


Assuntos
Seio Carotídeo , Medicina Legal , Morte Súbita , Patologia Legal , Humanos
9.
Phys Rev Lett ; 126(10): 102001, 2021 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-33784133

RESUMO

We report a study of the processes of e^{+}e^{-}→K^{+}D_{s}^{-}D^{*0} and K^{+}D_{s}^{*-}D^{0} based on e^{+}e^{-} annihilation samples collected with the BESIII detector operating at BEPCII at five center-of-mass energies ranging from 4.628 to 4.698 GeV with a total integrated luminosity of 3.7 fb^{-1}. An excess of events over the known contributions of the conventional charmed mesons is observed near the D_{s}^{-}D^{*0} and D_{s}^{*-}D^{0} mass thresholds in the K^{+} recoil-mass spectrum for events collected at sqrt[s]=4.681 GeV. The structure matches a mass-dependent-width Breit-Wigner line shape, whose pole mass and width are determined as (3982.5_{-2.6}^{+1.8}±2.1) MeV/c^{2} and (12.8_{-4.4}^{+5.3}±3.0) MeV, respectively. The first uncertainties are statistical and the second are systematic. The significance of the resonance hypothesis is estimated to be 5.3 σ over the contributions only from the conventional charmed mesons. This is the first candidate for a charged hidden-charm tetraquark with strangeness, decaying into D_{s}^{-}D^{*0} and D_{s}^{*-}D^{0}. However, the properties of the excess need further exploration with more statistics.

10.
Artigo em Inglês | MEDLINE | ID: mdl-33634834

RESUMO

BACKGROUND: Visceral function localization of the brain is very complex. For many years, people have been actively exploring the neural mechanism regulating visceral and substance metabolism, clarifying the complex relationship between the brain and peripheral nervous system related to the regulation of visceral activity, and analyzing its complex neural pathways. The brain is the advanced center of visceral function regulation. As an advanced center for substance metabolism and visceral regulation, the hippocampus is crucial for regulating visceral function. The liver is the core organ of material metabolism, and its afferent signals are mainly projected to the Nucleus of the solitary tract(NTS) through vagus nerve, and then they are projected to the hypothalamus and limbic system. MATERIALS AND METHODS: We placed a stereotaxic instrument on the head of each rat and performed craniotomy to open a window above the left hippocampus. We used gold-plated tungsten electrodes to monitor hippocampal neuronal discharges. Grounding was achieved using screws and silver wire. We electrically stimulated the liver branch of the vagus nerve and observed changes in hippocampal neuron discharges using a biological method; in this way, we identified hepatosensitive hippocampal region. We injected FluoroGold into this region and related brain areas. After 3 days, the rats were sacrificed and perfused; the hippocampi were fixed, dehydated, frozen, sectioned, and subjected to fluorescence microscopy. RESULTS: Nerve discharge frequency and amplitude significantly increased in the hippocampal CA3 region (AP: -4.9, ML: -5.1, DV: -5.0 mm). After FluoroGold was injected into the left hepatosensitive region in the hippocampus, labeled cells were found in the contralateral hippocampus, ipsilateral piriform cortex (PC), locus coeruleus (LC) and bilateral lateral hypothalamus (LHA); fluorescence in the ipsilateral hypothalamus was stronger than that of the contralateral hypothalamus. FluoroGold was injected into the LHA, PC, and LC; no labeled cells were found in the hippocampal CA3 region or in the control group. CONCLUSIONS: The hippocampal CA3 area of rats may contain a hepatosensitive region that plays important roles in the regulation of liver and other organ function. These region may receive input from the LHA, PC, and LC.

11.
Domest Anim Endocrinol ; 76: 106607, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33582417

RESUMO

There exists maternal immunological modification in maternal immune organs during early pregnancy in mammals. Gonadotropin releasing hormone (GnRH) is widely distributed in vertebrate tissues, including immune organs. However, it is unclear that early pregnancy induces expression of GnRH and GnRH receptor (GnRHR) in ovine immune organs. The objective of this study was to explore the expression of GnRH and GnRHR in main immune organs (thymus, lymph node, spleen, and liver) during early pregnancy in sheep. Ovine thymus, lymph node, spleen and liver were sampled at day 16 of estrous cycle, and days 13, 16, and 25 of pregnancy. The expression of GnRH and GnRHR was detected through real-time quantitative PCR, Western blot and immunohistochemistry analysis. The results indicated that early pregnancy induced upregulation of mRNA and protein levels of GnRH and GnRHR in the maternal lymph node, spleen and liver, and mRNA and protein of GnRH in the maternal thymus, but mRNA and protein of GnRHR decreased in the maternal thymus during early pregnancy. In summary, the mRNA and protein levels of GnRH and GnRHR were changed in maternal thymus, lymph node, spleen and liver in a tissue specific manner during early pregnancy in sheep.

12.
Zhonghua Yi Xue Za Zhi ; 101(4): 271-275, 2021 Jan 26.
Artigo em Chinês | MEDLINE | ID: mdl-33486936

RESUMO

Objectives: To analyze the reasons of residual partial anomalous pulmonary venous connection (PAPVC) after previous cardiac surgery, and summarize the strategies and experience for diagnosis and treatment of secondary correction operation. Methods: The clinical data of 18 patients who were admitted to Fuwai Hospital of Chinese Academy of Medical Sciences and Fuwai Yunnan Cardiovascular Hospital from June 2009 to May 2019 were retrospectively analyzed. All the patients underwent secondary cardiac surgery to treat PAPVC. The preoperative and intraoperative characteristics and postoperative complications of the patients were summarized and analyzed. Results: Totally, there were 7 male and 11 female cases, aged 1-49 years (median age: 4.5 years). In the first cardiac surgery, 3 patients were diagnosed with PAPVC, which existed after surgery. One patient was diagnosed with total anomalous pulmonary venous connection (TAPVC), but left PAPVC after surgery. The remaining 14 patients were all missed preoperative and intraoperative diagnosis. After the initial surgery, most patients had no significant symptoms (11/18), but PAPVC was found in 11 cases due to postoperative cardiac murmur or transthoracic echocardiography (TTE). In the secondary surgery, there were 4 cases of type A, 10 cases of type B, 2 cases of type C, no type D, and 2 cases of mixed type, respectively, according to Bordy classification. The diagnostic accuracy of TTE and CT angiography (CTA) was 50.0% and 92.9%, respectively. There was no death after the second surgery, but pulmonary vein occlusion, pericardial effusion, anastomotic stenosis and other complications occurred in 4 patients. Conclusions: The main causes of missed diagnosis of PAPVC are the undefined cardiac structural deformities before operation and the lack of careful exploration during the operation. TTE is simple and feasible to diagnose PAPVC, and it can improve the diagnostic accuracy when combined with CTA.


Assuntos
Procedimentos Cirúrgicos Cardíacos , Veias Pulmonares , Síndrome de Cimitarra , Adolescente , Adulto , Criança , Pré-Escolar , China , Feminino , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Veias Pulmonares/cirurgia , Estudos Retrospectivos , Síndrome de Cimitarra/cirurgia , Adulto Jovem
13.
Artigo em Inglês | LILACS | ID: biblio-1284447

RESUMO

This paper described the chemical compositions and antimicrobial activity of the essential oils from the leaves and stem of Amomum rubidumLamxay & N. S. Lý, collected from Bidoup Nui Ba National Park, Lam Dong, Vietnam. The essential oils were obtained by hydrodisitllation method while antimicrobial activity was evaluetd by microdilution broth susceptibility assay. The main constituents of the leaf essential oil were identified as 1,8-cineole (37.7%), δ-3-carene (19.5%) and limonene (16.3%) while δ-3-carene (21.9%), limonene (17.8%) and ß-phellandrene (14.6%) dominated in the stem essentialoil. The leaf and stem essential oils displayed stronger inhibition of Pseudomonas aeruginosa with MIC of 25 µg/mLand 50 µg/mL respectively. The stem essential oil was active against Candida albicans (MIC, 50 µg/mL) while both essential oils inhibited the growth of Fusarium oxysporum (MIC 50 µg/mL). This is the first report on chemical constituents and antimicrobial activity of the essential oils of A. rubidum.


Este artículo describe la composición química y la actividad antimicrobiana de aceites esenciales de las hojas y el tallo de Amomum rubidum Lamxay & N. S. Lý recolectados del Parque Nacional Bidoup Nui Ba, Lam Dong, Vietnam. Los aceites esenciales se obtuvieron mediante el método de hidrodisitilación, mientras que la actividad antimicrobiana se evaluó mediante un ensayo de susceptibilidad de caldo de microdilución. Los principales componentes del aceite esencial de la hoja se identificaron como 1,8-cineol (37,7%), δ-3-careno (19,5%) y limoneno (16,3%), mientras que δ-3-careno (21,9%), limoneno (17,8 %) y ß-felandreno (14,6%) dominaron en el aceite esencial del tallo. Los aceites esenciales de hoja y tallo mostraron una inhibición más fuerte de Pseudomonas aeruginosa con un MIC de 25 µg/mL y 50 µg/mL, respectivamente. El aceite esencial del tallo fue activo contra Candida albicans (MIC, 50 µg/mL) mientras que ambos aceites esenciales inhibieron el crecimiento de Fusarium oxysporum (MIC 50 µg/mL). Este es el primer informe sobre los componentes químicos y la actividad antimicrobiana de los aceites esenciales de A. rubidum.


Assuntos
Óleos Voláteis/farmacologia , Amomum/química , Anti-Infecciosos/farmacologia , Pseudomonas aeruginosa/efeitos dos fármacos , Candida albicans/efeitos dos fármacos , Óleos Voláteis/química , Testes de Sensibilidade Microbiana , Destilação , Cromatografia Gasosa , Caules de Planta , Folhas de Planta , Monoterpenos/análise , Fusarium/efeitos dos fármacos , Anti-Infecciosos/química
14.
Zhonghua Yi Xue Za Zhi ; 100(46): 3689-3693, 2020 Dec 15.
Artigo em Chinês | MEDLINE | ID: mdl-33342146

RESUMO

Objective: To investigate the effects of miR-191-5p on cell migration, clone formation and proliferation of gastric cancer (GC) cells. Methods: The level of miR-191-5p expression was detected by real-time reverse transcriptase-polymerase chain reaction (RT-PCR) in 60 paired GC tissues and their adjacent normal tissues. miR-191-5p overexpression was achieved by transfection of construct pcDNA-miR-191-5p into GC cells. The migration, clone formation and proliferation of GC cells were detected by the scratch wound assay, clone formation assay and cell counting kit-8 (CCK-8), respectively. Low expression of miR-191-5p was achieved with miRNA-191-5p inhibitor. The binding sites of cyclin-dependent kinase 6 (CDK6) and miR-191-5p were analyzed using TargetScan software, and the interaction of CDK6 and miR-191-5p was verified using dual-fluorescence reporter gene expression. Western blot (WB) was used to detect the effect of miR-191-5p on the expression of p21 and CDK6 proteins. Results: miR-191-5p decreased in 53 cases (88%) of GC tissues compared to their controls. Furthermore, overexpression of miR-191-5p effectively inhibited the migration, clone formation and proliferation of GC cells (P<0.05). Dual-fluorescence reporter confirmed that miR-191-5p bound to 3'UTR of CDK6. WB showed that pcDNA-miR-191-5p inhibited the CDK6 expression but promoted the p21. Conclusion: Down-regulation of miR-191-5p has a correlation with the progression of GC. Overexpression of miR-191-5p can decrease the expression of CDK6 and inhibit the growth of GC cells.


Assuntos
MicroRNAs , Neoplasias Gástricas , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Quinase 6 Dependente de Ciclina/genética , Quinase 6 Dependente de Ciclina/metabolismo , Regulação Neoplásica da Expressão Gênica , Humanos , MicroRNAs/genética , Invasividade Neoplásica/genética , Neoplasias Gástricas/genética
15.
Phys Rev Lett ; 125(14): 141802, 2020 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-33064551

RESUMO

Using 2.93 fb^{-1} of e^{+}e^{-} collision data collected at a center-of-mass energy of 3.773 GeV with the BESIII detector, the first observation of the doubly Cabibbo-suppressed decay D^{+}→K^{+}π^{+}π^{-}π^{0} is reported. After removing decays that contain narrow intermediate resonances, including D^{+}→K^{+}η, D^{+}→K^{+}ω, and D^{+}→K^{+}ϕ, the branching fraction of the decay D^{+}→K^{+}π^{+}π^{-}π^{0} is measured to be (1.13±0.08_{stat}±0.03_{syst})×10^{-3}. The ratio of branching fractions of D^{+}→K^{+}π^{+}π^{-}π^{0} over D^{+}→K^{-}π^{+}π^{+}π^{0} is found to be (1.81±0.15)%, which corresponds to (6.28±0.52)tan^{4}θ_{C}, where θ_{C} is the Cabibbo mixing angle. This ratio is significantly larger than the corresponding ratios for other doubly Cabibbo-suppressed decays. The asymmetry of the branching fractions of charge-conjugated decays D^{±}→K^{±}π^{±}π^{∓}π^{0} is also determined, and no evidence for CP violation is found. In addition, the first evidence for the D^{+}→K^{+}ω decay, with a statistical significance of 3.3σ, is presented and the branching fraction is measured to be B(D^{+}→K^{+}ω)=(5.7_{-2.1}^{+2.5}_{stat}±0.2_{syst})×10^{-5}.

16.
Phys Rev Lett ; 125(5): 052004, 2020 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-32794879

RESUMO

From 1310.6×10^{6} J/ψ and 448.1×10^{6} ψ(3686) events collected with the BESIII experiment, we report the first observation of Σ^{+} and Σ[over ¯]^{-} spin polarization in e^{+}e^{-}→J/ψ[ψ(3686)]→Σ^{+}Σ[over ¯]^{-} decays. The relative phases of the form factors ΔΦ have been measured to be (-15.5±0.7±0.5)° and (21.7±4.0±0.8)° with J/ψ and ψ(3686) data, respectively. The nonzero value of ΔΦ allows for a direct and simultaneous measurement of the decay asymmetry parameters of Σ^{+}→pπ^{0}(α_{0}=-0.998±0.037±0.009) and Σ[over ¯]^{-}→p[over ¯]π^{0}(α[over ¯]_{0}=0.990±0.037±0.011), the latter value being determined for the first time. The average decay asymmetry, (α_{0}-α[over ¯]_{0})/2, is calculated to be -0.994±0.004±0.002. The CP asymmetry A_{CP,Σ}=(α_{0}+α[over ¯]_{0})/(α_{0}-α[over ¯]_{0})=-0.004±0.037±0.010 is extracted for the first time, and is found to be consistent with CP conservation.

17.
Phys Rev Lett ; 124(24): 241802, 2020 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-32639796

RESUMO

We report the most precise measurements to date of the strong-phase parameters between D^{0} and D[over ¯]^{0} decays to K_{S,L}^{0}π^{+}π^{-} using a sample of 2.93 fb^{-1} of e^{+}e^{-} annihilation data collected at a center-of-mass energy of 3.773 GeV with the BESIII detector at the BEPCII collider. Our results provide the key inputs for a binned model-independent determination of the Cabibbo-Kobayashi-Maskawa angle γ/ϕ_{3} with B decays. Using our results, the decay model sensitivity to the γ/ϕ_{3} measurement is expected to be between 0.7° and 1.2°, approximately a factor of three smaller than that achievable with previous measurements, based on the studies of the simulated data. The improved precision of this work ensures that measurements of γ/ϕ_{3} will not be limited by knowledge of strong phases for the next decade. Furthermore, our results provide critical input for other flavor-physics investigations, including charm mixing, other measurements of CP violation, and the measurement of strong-phase parameters for other D-decay modes.

18.
Phys Rev Lett ; 124(24): 242001, 2020 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-32639837

RESUMO

The processes X(3872)→D^{*0}D[over ¯]^{0}+c.c.,γJ/ψ,γψ(2S), and γD^{+}D^{-} are searched for in a 9.0 fb^{-1} data sample collected at center-of-mass energies between 4.178 and 4.278 GeV with the BESIII detector. We observe X(3872)→D^{*0}D^{0}[over ¯]+c.c. and find evidence for X(3872)→γJ/ψ with statistical significances of 7.4σ and 3.5σ, respectively. No evident signals for X(3872)→γψ(2S) and γD^{+}D^{-} are found, and the upper limit on the relative branching ratio R_{γψ}≡{B[X(3872)→γψ(2S)]}/{B[X(3872)→γJ/ψ]}<0.59 is set at 90% confidence level. Measurements of branching ratios relative to decay X(3872)→π^{+}π^{-}J/ψ are also reported for decays X(3872)→D^{*0}D^{0}[over ¯]+c.c.,γψ(2S),γJ/ψ, and γD^{+}D^{-}, as well as the non-D^{*0}D^{0}[over ¯] three-body decays π^{0}D^{0}D^{0}[over ¯] and γD^{0}D^{0}[over ¯].

19.
Phys Rev Lett ; 124(24): 241803, 2020 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-32639841

RESUMO

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, we report the first measurements of the absolute branching fractions of 14 hadronic D^{0(+)} decays to exclusive final states with an η, e.g., D^{0}→K^{-}π^{+}η, K_{S}^{0}π^{0}η, K^{+}K^{-}η, K_{S}^{0}K_{S}^{0}η, K^{-}π^{+}π^{0}η, K_{S}^{0}π^{+}π^{-}η, K_{S}^{0}π^{0}π^{0}η, and π^{+}π^{-}π^{0}η; D^{+}→K_{S}^{0}π^{+}η, K_{S}^{0}K^{+}η, K^{-}π^{+}π^{+}η, K_{S}^{0}π^{+}π^{0}η, π^{+}π^{+}π^{-}η, and π^{+}π^{0}π^{0}η. Among these decays, the D^{0}→K^{-}π^{+}η and D^{+}→K_{S}^{0}π^{+}η decays have the largest branching fractions, which are B(D^{0}→K^{-}π^{+}η)=(1.853±0.025_{stat}±0.031_{syst})% and B(D^{+}→K_{S}^{0}π^{+}η)=(1.309±0.037_{stat}±0.031_{syst})%, respectively. The charge-parity asymmetries for the six decays with highest event yields are determined, and no statistically significant charge-parity violation is found.

20.
Phys Rev Lett ; 124(23): 231801, 2020 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-32603168

RESUMO

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^{+}ν_{µ} decay to be B_{D^{+}→ηµ^{+}ν_{µ}}=(10.4±1.0_{stat}±0.5_{syst})×10^{-4}. Using the world averaged value of B_{D^{+}→ηe^{+}ν_{e}}, the ratio of the two branching fractions is determined to be B_{D^{+}→ηµ^{+}ν_{µ}}/B_{D^{+}→ηe^{+}ν_{e}}=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 |V_{cd}| to be f_{+}^{η}(0)|V_{cd}|=0.087±0.008_{stat}±0.002_{syst}. Taking the input of |V_{cd}| from the global fit in the standard model, we determine f_{+}^{η}(0)=0.39±0.04_{stat}±0.01_{syst}. On the other hand, using the value of f_{+}^{η}(0) calculated in theory, we find |V_{cd}|=0.242±0.022_{stat}±0.006_{syst}±0.033_{theory}.

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