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Determination of Spin-Parity Quantum Numbers of X(2370) as 0^{-+} from J/ψ→γK_{S}^{0}K_{S}^{0}η^{'}. PHYSICAL REVIEW LETTERS 2024; 132:181901. [PMID: 38759175 DOI: 10.1103/physrevlett.132.181901] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/08/2023] [Revised: 03/05/2024] [Accepted: 03/28/2024] [Indexed: 05/19/2024]
Abstract
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.
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2
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Observation of Structures in the Processes e^{+}e^{-}→ωχ_{c1} and ωχ_{c2}. PHYSICAL REVIEW LETTERS 2024; 132:161901. [PMID: 38701481 DOI: 10.1103/physrevlett.132.161901] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/26/2024] [Revised: 03/13/2024] [Accepted: 03/22/2024] [Indexed: 05/05/2024]
Abstract
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.
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Coupled-Channel Analysis of the χ_{c1}(3872) Line Shape with BESIII Data. PHYSICAL REVIEW LETTERS 2024; 132:151903. [PMID: 38682963 DOI: 10.1103/physrevlett.132.151903] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/05/2023] [Revised: 01/03/2024] [Accepted: 03/11/2024] [Indexed: 05/01/2024]
Abstract
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.
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4
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Observation of the Anomalous Shape of X(1840) in J/ψ→γ3(π^{+}π^{-}) Indicating a Second Resonance Near pp[over ¯] Threshold. PHYSICAL REVIEW LETTERS 2024; 132:151901. [PMID: 38682972 DOI: 10.1103/physrevlett.132.151901] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/02/2023] [Revised: 01/16/2024] [Accepted: 02/23/2024] [Indexed: 05/01/2024]
Abstract
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.
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Study of the f_{0}(980) and f_{0}(500) Scalar Mesons through the Decay D_{s}^{+}→π^{+}π^{-}e^{+}ν_{e}. PHYSICAL REVIEW LETTERS 2024; 132:141901. [PMID: 38640399 DOI: 10.1103/physrevlett.132.141901] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/23/2023] [Revised: 11/29/2023] [Accepted: 02/28/2024] [Indexed: 04/21/2024]
Abstract
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.
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Post-traumatic hematoma of the "transdural" virtual space. A possible cause of incorrect surgical treatment of epidural hematomas. Br J Neurosurg 2024; 38:241-243. [PMID: 33000956 DOI: 10.1080/02688697.2020.1828275] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2020] [Revised: 09/16/2020] [Accepted: 09/21/2020] [Indexed: 10/23/2022]
Abstract
The space existing between the external and internal dural layer has been anatomically described as a virtual space; no clear clinical significance has been given to it to date. We hereby describe a case of a child with what was expected to be a purely epidural hematoma, at surgery, was found to be composed of two equally coexistent components, one in the epidural space and the second one between the two dural layers. The recognition of a possible involvement of the transdural space in the case of post-traumatic epidural hematomas is relevant for a correct conclusion of the surgical treatment of epidural hematomas, extensively considered basic practice among neurosurgical procedures.
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Intracranial complications of sinogenic and otogenic infections in children: an ESPN survey on their occurrence in the pre-COVID and post-COVID era. Childs Nerv Syst 2024; 40:1221-1237. [PMID: 38456922 DOI: 10.1007/s00381-024-06332-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/29/2023] [Accepted: 02/21/2024] [Indexed: 03/09/2024]
Abstract
BACKGROUND COVID-19 pandemic is thought to have changed the epidemiology of some pediatric neurosurgical disease: among them are the intracranial complications of sinusitis and otitis (ICSO). According to some studies on a limited number of cases, both streptococci-related sinusitis and ICSO would have increased immediately after the pandemic, although the reason is not clear yet (seasonal changes versus pandemic-related effects). The goal of the present survey of the European Society for Pediatric Neurosurgery (ESPN) was to collect a large number of cases from different European countries encompassing the pre-COVID (2017-2019), COVID (2020-2021), and post-COVID period (2022-June 2023) looking for possible epidemiological and/or clinical changes. MATERIAL AND METHODS An English language questionnaire was sent to ESPN members about year of the event, patient's age and gender, presence of immune-deficit or other favoring risk factors, COVID infection, signs and symptoms at onset, site of primary infection, type of intracranial complication, identified germ, type and number of surgical operations, type and duration of medical treatment, clinical and radiological outcome, duration of the follow-up. RESULTS Two hundred fifty-four cases were collected by 30 centers coming from 14 different European countries. There was a statistically significant difference between the post-COVID period (129 children, 86 cases/year, 50.7% of the whole series) and the COVID (40 children, 20 cases/year, 15.7%) or the pre-COVID period (85 children, 28.3 cases/year, 33.5%). Other significant differences concerned the presence of predisposing factors/concurrent diseases (higher in the pre-COVID period) and previous COVID infection (higher in the post-COVID period). No relevant differences occurred as far as demographic, microbiological, clinical, radiological, outcome, morbidity, and mortality data were concerned. Paranasal sinuses and middle ear/mastoid were the most involved primary site of infection (71% and 27%, respectively), while extradural or subdural empyema and brain abscess were the most common ICSO (73% and 17%, respectively). Surgery was required in 95% of cases (neurosurgical and ENT procedure in 71% and 62% of cases, respectively) while antibiotics in 99% of cases. After a 12.4-month follow-up, a full clinical and radiological recovery was obtained in 85% and 84% of cases, respectively. The mortality rate was 2.7%. CONCLUSIONS These results suggest that the occurrence of ICSO was significantly increased after the pandemic. Such an increase seems to be related to the indirect effects of the pandemic (e.g., immunity debt) rather than to a direct effect of COVID infection or to seasonal fluctuations. ICSO remain challenging diseases but the pandemic did not affect the management strategies nor their prognosis. The epidemiological change of sinusitis/otitis and ICSO should alert about the appropriate follow-up of children with sinusitis/otitis.
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Observation of D^{+}→K_{S}^{0}a_{0}(980)^{+} in the Amplitude Analysis of D^{+}→K_{S}^{0}π^{+}η. PHYSICAL REVIEW LETTERS 2024; 132:131903. [PMID: 38613307 DOI: 10.1103/physrevlett.132.131903] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/23/2023] [Revised: 01/10/2024] [Accepted: 02/14/2024] [Indexed: 04/14/2024]
Abstract
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.
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Observation of Significant Flavor-SU(3) Breaking in the Kaon Wave Function at 12<Q^{2}<25 GeV^{2} and Discovery of the Charmless Decay ψ(3770)→K_{S}^{0}K_{L}^{0}. PHYSICAL REVIEW LETTERS 2024; 132:131901. [PMID: 38613263 DOI: 10.1103/physrevlett.132.131901] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/19/2023] [Revised: 02/11/2024] [Accepted: 02/13/2024] [Indexed: 04/14/2024]
Abstract
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
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10
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Investigation of the ΔI=1/2 Rule and Test of CP Symmetry through the Measurement of Decay Asymmetry Parameters in Ξ^{-} Decays. PHYSICAL REVIEW LETTERS 2024; 132:101801. [PMID: 38518329 DOI: 10.1103/physrevlett.132.101801] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/26/2023] [Accepted: 02/01/2024] [Indexed: 03/24/2024]
Abstract
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.
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Observation of D_{s}^{+}→η^{'}μ^{+}ν_{μ}, Precision Test of Lepton Flavor Universality with D_{s}^{+}→η^{(')}l^{+}ν_{l}, and First Measurements of D_{s}^{+}→η^{(')}μ^{+}ν_{μ} Decay Dynamics. PHYSICAL REVIEW LETTERS 2024; 132:091802. [PMID: 38489649 DOI: 10.1103/physrevlett.132.091802] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/25/2023] [Revised: 01/25/2024] [Accepted: 01/26/2024] [Indexed: 03/17/2024]
Abstract
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.
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12
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Determination of the Σ^{+} Timelike Electromagnetic Form Factors. PHYSICAL REVIEW LETTERS 2024; 132:081904. [PMID: 38457707 DOI: 10.1103/physrevlett.132.081904] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/01/2023] [Revised: 11/24/2023] [Accepted: 01/12/2024] [Indexed: 03/10/2024]
Abstract
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.
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First Measurement of the Decay Asymmetry in the Pure W-Boson-Exchange Decay Λ_{c}^{+}→Ξ^{0}K^{+}. PHYSICAL REVIEW LETTERS 2024; 132:031801. [PMID: 38307076 DOI: 10.1103/physrevlett.132.031801] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/06/2023] [Accepted: 11/30/2023] [Indexed: 02/04/2024]
Abstract
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.
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Search for Evidence of Baryogenesis and Dark Matter in B^{+}→ψ_{D}+p Decays at BABAR. PHYSICAL REVIEW LETTERS 2023; 131:201801. [PMID: 38039482 DOI: 10.1103/physrevlett.131.201801] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/19/2023] [Accepted: 10/12/2023] [Indexed: 12/03/2023]
Abstract
A new dark sector antibaryon, denoted ψ_{D}, could be produced in decays of B mesons. This Letter presents a search for B^{+}→ψ_{D}+p (and the charge conjugate) decays in e^{+}e^{-} annihilations at 10.58 GeV, using data collected in the BABAR experiment. Data corresponding to an integrated luminosity of 398 fb^{-1} are analyzed. No evidence for a signal is observed. Branching fraction upper limits in the range from 10^{-7}-10^{-5} are obtained at 90% confidence level for masses of 1.0
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Test of CP Symmetry in Hyperon to Neutron Decays. PHYSICAL REVIEW LETTERS 2023; 131:191802. [PMID: 38000397 DOI: 10.1103/physrevlett.131.191802] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/30/2023] [Accepted: 10/03/2023] [Indexed: 11/26/2023]
Abstract
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.
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Measurement of Energy-Dependent Pair-Production Cross Section and Electromagnetic Form Factors of a Charmed Baryon. PHYSICAL REVIEW LETTERS 2023; 131:191901. [PMID: 38000396 DOI: 10.1103/physrevlett.131.191901] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/17/2023] [Revised: 08/29/2023] [Accepted: 09/15/2023] [Indexed: 11/26/2023]
Abstract
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.
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Tests of Light-Lepton Universality in Angular Asymmetries of B^{0}→D^{*-}ℓν Decays. PHYSICAL REVIEW LETTERS 2023; 131:181801. [PMID: 37977641 DOI: 10.1103/physrevlett.131.181801] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/09/2023] [Accepted: 09/29/2023] [Indexed: 11/19/2023]
Abstract
We present the first comprehensive tests of the universality of the light leptons in the angular distributions of semileptonic B^{0}-meson decays to charged spin-1 charmed mesons. We measure five angular-asymmetry observables as functions of the decay recoil that are sensitive to lepton-universality-violating contributions. We use events where one neutral B is fully reconstructed in ϒ(4S)→BB[over ¯] decays in data corresponding to 189 fb^{-1} integrated luminosity from electron-positron collisions collected with the Belle II detector. We find no significant deviation from the standard model expectations.
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Precise Measurement of the D_{s}^{+} Lifetime at Belle II. PHYSICAL REVIEW LETTERS 2023; 131:171803. [PMID: 37955504 DOI: 10.1103/physrevlett.131.171803] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/01/2023] [Accepted: 09/14/2023] [Indexed: 11/14/2023]
Abstract
We measure the lifetime of the D_{s}^{+} meson using a data sample of 207 fb^{-1} collected by the Belle II experiment running at the SuperKEKB asymmetric-energy e^{+}e^{-} collider. The lifetime is determined by fitting the decay-time distribution of a sample of 116×10^{3} D_{s}^{+}→ϕπ^{+} decays. Our result is τ_{D_{s}^{+}}=(499.5±1.7±0.9) fs, where the first uncertainty is statistical and the second is systematic. This result is significantly more precise than previous measurements.
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19
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Determination of Spin-Parity Quantum Numbers for the Narrow Structure near the pΛ[over ¯] Threshold in e^{+}e^{-}→pK^{-}Λ[over ¯]+c.c. PHYSICAL REVIEW LETTERS 2023; 131:151901. [PMID: 37897776 DOI: 10.1103/physrevlett.131.151901] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/06/2023] [Revised: 08/22/2023] [Accepted: 09/15/2023] [Indexed: 10/30/2023]
Abstract
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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20
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Precise Measurement of the e^{+}e^{-}→D_{s}^{*+}D_{s}^{*-} Cross Sections at Center-of-Mass Energies from Threshold to 4.95 GeV. PHYSICAL REVIEW LETTERS 2023; 131:151903. [PMID: 37897771 DOI: 10.1103/physrevlett.131.151903] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/19/2023] [Revised: 08/16/2023] [Accepted: 08/29/2023] [Indexed: 10/30/2023]
Abstract
The process e^{+}e^{-}→D_{s}^{*+}D_{s}^{*-} is studied with a semi-inclusive method using data samples at center-of-mass energies from threshold to 4.95 GeV collected with the BESIII detector operating at the Beijing Electron Positron Collider. The Born cross sections of the process are measured for the first time with high precision in this energy region. Two resonance structures are observed in the energy-dependent cross sections around 4.2 and 4.4 GeV. By fitting the cross sections with a coherent sum of three Breit-Wigner amplitudes and one phase-space amplitude, the two significant structures are assigned masses of (4186.8±8.7±30) and (4414.6±3.4±6.1) MeV/c^{2}, widths of (55±15±53) and (122.5±7.5±8.1) MeV, where the first errors are statistical and the second ones are systematic. The inclusion of a third Breit-Wigner amplitude is necessary to describe a structure around 4.79 GeV.
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21
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First Experimental Study of the Purely Leptonic Decay D_{s}^{*+}→e^{+}ν_{e}. PHYSICAL REVIEW LETTERS 2023; 131:141802. [PMID: 37862669 DOI: 10.1103/physrevlett.131.141802] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/25/2023] [Revised: 07/25/2023] [Accepted: 09/05/2023] [Indexed: 10/22/2023]
Abstract
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.
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22
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Search for Λ[over ¯]-Λ Baryon-Number-Violating Oscillations in the Decay J/ψ→pK^{-}Λ[over ¯]+c.c. PHYSICAL REVIEW LETTERS 2023; 131:121801. [PMID: 37802947 DOI: 10.1103/physrevlett.131.121801] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/08/2023] [Revised: 08/14/2023] [Accepted: 08/29/2023] [Indexed: 10/08/2023]
Abstract
We report on the first search for Λ[over ¯]-Λ oscillations in the decay J/ψ→pK^{-}Λ[over ¯]+c.c. by analyzing 1.31×10^{9} J/ψ events accumulated with the BESIII detector at the BEPCII collider. The J/ψ events are produced using e^{+}e^{-} collisions at a center of mass energy sqrt[s]=3.097 GeV. No evidence for hyperon oscillations is observed. The upper limit for the oscillation rate of Λ[over ¯] to Λ hyperons is determined to be P(Λ)=[B(J/ψ→pK^{-}Λ+c.c.)/B(J/ψ→pK^{-}Λ[over ¯]+c.c.)]<4.4×10^{-6} corresponding to an oscillation parameter δm_{ΛΛ[over ¯]} of less than 3.8×10^{-18} GeV at the 90% confidence level.
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23
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Search for a τ^{+}τ^{-} Resonance in e^{+}e^{-}→μ^{+}μ^{-}τ^{+}τ^{-} Events with the Belle II Experiment. PHYSICAL REVIEW LETTERS 2023; 131:121802. [PMID: 37802942 DOI: 10.1103/physrevlett.131.121802] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/22/2023] [Accepted: 08/08/2023] [Indexed: 10/08/2023]
Abstract
We report the first search for a nonstandard-model resonance decaying into τ pairs in e^{+}e^{-}→μ^{+}μ^{-}τ^{+}τ^{-} events in the 3.6-10 GeV/c^{2} mass range. We use a 62.8 fb^{-1} sample of e^{+}e^{-} collisions collected at a center-of-mass energy of 10.58 GeV by the Belle II experiment at the SuperKEKB collider. The analysis probes three different models predicting a spin-1 particle coupling only to the heavier lepton families, a Higgs-like spin-0 particle that couples preferentially to charged leptons (leptophilic scalar), and an axionlike particle, respectively. We observe no evidence for a signal and set exclusion limits at 90% confidence level on the product of cross section and branching fraction into τ pairs, ranging from 0.7 to 24 fb, and on the couplings of these processes. We obtain world-leading constraints on the couplings for the leptophilic scalar model for masses above 6.5 GeV/c^{2} and for the axionlike particle model over the entire mass range.
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24
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Measurement of CP Violation in B^{0}→K_{S}^{0}π^{0} Decays at Belle II. PHYSICAL REVIEW LETTERS 2023; 131:111803. [PMID: 37774261 DOI: 10.1103/physrevlett.131.111803] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/15/2023] [Accepted: 07/26/2023] [Indexed: 10/01/2023]
Abstract
We report a measurement of the CP-violating parameters C and S in B^{0}→K_{S}^{0}π^{0} decays at Belle II using a sample of 387×10^{6} BB[over ¯] events recorded in e^{+}e^{-} collisions at a center-of-mass energy corresponding to the ϒ(4S) resonance. These parameters are determined by fitting the proper decay-time distribution of a sample of 415 signal events. We obtain C=-0.04_{-0.15}^{+0.14}±0.05 and S=0.75_{-0.23}^{+0.20}±0.04, where the first uncertainties are statistical and the second are systematic.
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25
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Test of Light-Lepton Universality in the Rates of Inclusive Semileptonic B-Meson Decays at Belle II. PHYSICAL REVIEW LETTERS 2023; 131:051804. [PMID: 37595249 DOI: 10.1103/physrevlett.131.051804] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/25/2023] [Revised: 05/03/2023] [Accepted: 05/11/2023] [Indexed: 08/20/2023]
Abstract
We present the first measurement of the ratio of branching fractions of inclusive semileptonic B-meson decays, R(X_{e/μ})=B(B→Xeν)/B(B→Xμν), a precision test of electron-muon universality, using data corresponding to 189 fb^{-1} from electron-positron collisions collected with the Belle II detector. In events where the partner B meson is fully reconstructed, we use fits to the lepton momentum spectra above 1.3 GeV/c to obtain R(X_{e/μ})=1.007±0.009(stat)±0.019(syst), which is the most precise lepton-universality test of its kind and agrees with the standard-model expectation.
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26
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First Study of Reaction Ξ^{0}n→Ξ^{-}p Using Ξ^{0}-Nucleus Scattering at an Electron-Positron Collider. PHYSICAL REVIEW LETTERS 2023; 130:251902. [PMID: 37418739 DOI: 10.1103/physrevlett.130.251902] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/27/2023] [Revised: 05/20/2023] [Accepted: 05/25/2023] [Indexed: 07/09/2023]
Abstract
Using (1.0087±0.0044)×10^{10} J/ψ events collected with the BESIII detector at the BEPCII storage ring, the process Ξ^{0}n→Ξ^{-}p is studied, where the Ξ^{0} baryon is produced in the process J/ψ→Ξ^{0}Ξ[over ¯]^{0} and the neutron is a component of the ^{9}Be, ^{12}C, and ^{197}Au nuclei in the beam pipe. A clear signal is observed with a statistical significance of 7.1σ. The cross section of the reaction Ξ^{0}+^{9}Be→Ξ^{-}+p+^{8}Be is determined to be σ(Ξ^{0}+^{9}Be→Ξ^{-}+p+^{8}Be)=(22.1±5.3_{stat}±4.5_{sys}) mb at the Ξ^{0} momentum of 0.818 GeV/c, where the first uncertainty is statistical and the second is systematic. No significant H-dibaryon signal is observed in the Ξ^{-}p final state. This is the first study of hyperon-nucleon interactions in electron-positron collisions and opens up a new direction for such research.
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27
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Search for an Invisible Z^{'} in a Final State with Two Muons and Missing Energy at Belle II. PHYSICAL REVIEW LETTERS 2023; 130:231801. [PMID: 37354391 DOI: 10.1103/physrevlett.130.231801] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/07/2022] [Accepted: 04/19/2023] [Indexed: 06/26/2023]
Abstract
The L_{μ}-L_{τ} extension of the standard model predicts the existence of a lepton-flavor-universality-violating Z^{'} boson that couples only to the heavier lepton families. We search for such a Z^{'} through its invisible decay in the process e^{+}e^{-}→μ^{+}μ^{-}Z^{'}. We use a sample of electron-positron collisions at a center-of-mass energy of 10.58 GeV collected by the Belle II experiment in 2019-2020, corresponding to an integrated luminosity of 79.7 fb^{-1}. We find no excess over the expected standard-model background. We set 90%-confidence-level upper limits on the cross section for this process as well as on the coupling of the model, which ranges from 3×10^{-3} at low Z^{'} masses to 1 at Z^{'} masses of 8 GeV/c^{2}.
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28
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Measurements of Normalized Differential Cross Sections of Inclusive π^{0} and K_{S}^{0} Production in e^{+}e^{-} Annihilation at Energies from 2.2324 to 3.6710 GeV. PHYSICAL REVIEW LETTERS 2023; 130:231901. [PMID: 37354421 DOI: 10.1103/physrevlett.130.231901] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/21/2022] [Revised: 03/22/2023] [Accepted: 04/03/2023] [Indexed: 06/26/2023]
Abstract
Based on electron positron collision data collected with the BESIII detector operating at the BEPCII storage rings, the differential cross sections of inclusive π^{0} and K_{S}^{0} production as a function of hadron momentum, normalized by the total cross section of the e^{+}e^{-}→hadrons process, are measured at six center-of-mass energies from 2.2324 to 3.6710 GeV. Our results, which cover a relative hadron energy range from 0.1 to 0.9, significantly deviate from several theoretical calculations based on existing fragmentation functions.
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29
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Precision Measurement of the Decay Σ^{+}→pγ in the Process J/ψ→Σ^{+}Σ[over ¯]^{-}. PHYSICAL REVIEW LETTERS 2023; 130:211901. [PMID: 37295102 DOI: 10.1103/physrevlett.130.211901] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/27/2023] [Revised: 03/29/2023] [Accepted: 05/08/2023] [Indexed: 06/12/2023]
Abstract
Using (10 087±44)×10^{6} J/ψ events collected with the BESIII detector, the radiative hyperon decay Σ^{+}→pγ is studied at an electron-positron collider experiment for the first time. The absolute branching fraction is measured to be (0.996±0.021_{stat}±0.018_{syst})×10^{-3}, which is lower than its world average value by 4.2 standard deviations. Its decay asymmetry parameter is determined to be -0.652±0.056_{stat}±0.020_{syst}. The branching fraction and decay asymmetry parameter are the most precise to date, and the accuracies are improved by 78% and 34%, respectively.
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30
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A novel multiwalled carbon nanotube-cyclodextrin nanocomposite for solid-phase microextraction-gas chromatography-mass spectrometry determination of polycyclic aromatic hydrocarbons in snow samples. Mikrochim Acta 2023; 190:212. [PMID: 37171627 PMCID: PMC10181969 DOI: 10.1007/s00604-023-05799-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2023] [Accepted: 04/13/2023] [Indexed: 05/13/2023]
Abstract
Novel solid-phase microextraction coatings based on the use of multiwalled carbon nanotube-cyclodextrin (MWCNT-CD) nanocomposites were developed for the determination of 16-priority polycyclic aromatic hydrocarbons at ultratrace levels in snow samples. The performance of both β- and γ-CD was tested to increase the detection capabilities towards the heaviest and most lipophilic compounds, i.e., five- and six-ring PAHs. To facilitate the interactions of MWCNTs with CDs, an oxidation procedure using both HNO3 and H2O2 was applied, obtaining superior results using MWCNTs-H2O2-γ-CD fiber. Detection and quantitation limits below 0.7 and 2.3 ng/L, RSD lower than 21%, and recoveries of 88(± 2)-119.8(± 0.4)% proved the reliability of the developed method for the determination of PAHs at ultratrace levels. The complexation capability of the γ-CD was also demonstrated in solution by NMR and fluorescence spectroscopy studies and at solid state by XRD analysis. Finally, snow samples collected in the ski area of Dolomiti di Brenta were analyzed, showing a different distribution of the 16 priority PAHs, being naphthalene, phenanthrene, fluoranthene, and pyrene the only compounds detected in all the analyzed samples.
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31
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Search for Lepton-Flavor-Violating τ Decays to a Lepton and an Invisible Boson at Belle II. PHYSICAL REVIEW LETTERS 2023; 130:181803. [PMID: 37204890 DOI: 10.1103/physrevlett.130.181803] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/07/2022] [Accepted: 02/23/2023] [Indexed: 05/21/2023]
Abstract
We search for lepton-flavor-violating τ^{-}→e^{-}α and τ^{-}→μ^{-}α decays, where α is an invisible spin-0 boson. The search uses electron-positron collisions at 10.58 GeV center-of-mass energy with an integrated luminosity of 62.8 fb^{-1}, produced by the SuperKEKB collider and collected with the Belle II detector. We search for an excess in the lepton-energy spectrum of the known τ^{-}→e^{-}ν[over ¯]_{e}ν_{τ} and τ^{-}→μ^{-}ν[over ¯]_{μ}ν_{τ} decays. We report 95% confidence-level upper limits on the branching-fraction ratio B(τ^{-}→e^{-}α)/B(τ^{-}→e^{-}ν[over ¯]_{e}ν_{τ}) in the range (1.1-9.7)×10^{-3} and on B(τ^{-}→μ^{-}α)/B(τ^{-}→μ^{-}ν[over ¯]_{μ}ν_{τ}) in the range (0.7-12.2)×10^{-3} for α masses between 0 and 1.6 GeV/c^{2}. These results provide the most stringent bounds on invisible boson production from τ decays.
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32
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Measurements of the Electric and Magnetic Form Factors of the Neutron for Timelike Momentum Transfer. PHYSICAL REVIEW LETTERS 2023; 130:151905. [PMID: 37115883 DOI: 10.1103/physrevlett.130.151905] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/15/2022] [Revised: 02/27/2023] [Accepted: 03/23/2023] [Indexed: 06/19/2023]
Abstract
We present the first measurements of the electric and magnetic form factors of the neutron in the timelike (positive q^{2}) region as function of four-momentum transfer. We explored the differential cross sections of the reaction e^{+}e^{-}→n[over ¯]n with data collected with the BESIII detector at the BEPCII accelerator, corresponding to an integrated luminosity of 354.6 pb^{-1} in total at twelve center-of-mass energies between sqrt[s]=2.0-2.95 GeV. A relative uncertainty of 18% and 12% for the electric and magnetic form factors, respectively, is achieved at sqrt[s]=2.3935 GeV. Our results are comparable in accuracy to those from electron scattering in the comparable spacelike region of four-momentum transfer. The electromagnetic form factor ratio R_{em}≡|G_{E}|/|G_{M}| is within the uncertainties close to unity. We compare our result on |G_{E}| and |G_{M}| to recent model predictions, and the measurements in the spacelike region to test the analyticity of electromagnetic form factors.
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33
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Observation of a New X(3872) Production Process e^{+}e^{-}→ωX(3872). PHYSICAL REVIEW LETTERS 2023; 130:151904. [PMID: 37115900 DOI: 10.1103/physrevlett.130.151904] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/14/2022] [Revised: 03/16/2023] [Accepted: 03/20/2023] [Indexed: 06/19/2023]
Abstract
Using 4.7 fb^{-1} of e^{+}e^{-} collision data at center-of-mass energies from 4.661 to 4.951 GeV collected by the BESIII detector at the BEPCII collider, we observe the X(3872) production process e^{+}e^{-}→ωX(3872) for the first time. The significance is 7.8σ, including both the statistical and systematic uncertainties. The e^{+}e^{-}→ωX(3872) Born cross section and the corresponding upper limit at 90% confidence level at each energy point are reported. The line shape of the cross section indicates that the ωX(3872) signals may be from the decays of some nontrivial structures.
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34
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Matrix Gla Protein drives stemness and tumor initiation in ovarian cancer. Cell Death Dis 2023; 14:220. [PMID: 36977707 PMCID: PMC10050398 DOI: 10.1038/s41419-023-05760-w] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2023] [Revised: 03/18/2023] [Accepted: 03/20/2023] [Indexed: 03/30/2023]
Abstract
Ovarian cancer (OC) displays the highest mortality among gynecological tumors, mainly due to early peritoneal dissemination, the high frequency of tumor relapse following primary debulking, and the development of chemoresistance. All these events are thought to be initiated and sustained by a subpopulation of neoplastic cells, termed ovarian cancer stem cells (OCSC), that are endowed with self-renewing and tumor-initiating properties. This implies that interfering with OCSC function should offer novel therapeutic perspectives to defeat OC progression. To this aim, a better understanding of the molecular and functional makeup of OCSC in clinically relevant model systems is essential. We have profiled the transcriptome of OCSC vs. their bulk cell counterpart from a panel of patient-derived OC cell cultures. This revealed that Matrix Gla Protein (MGP), classically known as a calcification-preventing factor in cartilage and blood vessels, is markedly enriched in OCSC. Functional assays showed that MGP confers several stemness-associated traits to OC cells, including a transcriptional reprogramming. Patient-derived organotypic cultures pointed to the peritoneal microenvironment as a major inducer of MGP expression in OC cells. Furthermore, MGP was found to be necessary and sufficient for tumor initiation in OC mouse models, by shortening tumor latency and increasing dramatically the frequency of tumor-initiating cells. Mechanistically, MGP-driven OC stemness was mediated by the stimulation of Hedgehog signaling, in particular through the induction of the Hedgehog effector GLI1, thus highlighting a novel MGP/Hedgehog pathway axis in OCSC. Finally, MGP expression was found to correlate with poor prognosis in OC patients, and was increased in tumor tissue after chemotherapy, supporting the clinical relevance of our findings. Thus, MGP is a novel driver in OCSC pathophysiology, with a major role in stemness and in tumor initiation.
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35
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Observation of Three Charmoniumlike States with J^{PC}=1^{--} in e^{+}e^{-}→D^{*0}D^{*-}π^{+}. PHYSICAL REVIEW LETTERS 2023; 130:121901. [PMID: 37027853 DOI: 10.1103/physrevlett.130.121901] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/18/2023] [Revised: 02/16/2023] [Accepted: 02/24/2023] [Indexed: 06/19/2023]
Abstract
The Born cross sections of the process e^{+}e^{-}→D^{*0}D^{*-}π^{+} at center-of-mass energies from 4.189 to 4.951 GeV are measured for the first time. The data samples used correspond to an integrated luminosity of 17.9 fb^{-1} and were collected by the BESIII detector operating at the BEPCII storage ring. Three enhancements around 4.20, 4.47, and 4.67 GeV are visible. The resonances have masses of 4209.6±4.7±5.9 MeV/c^{2}, 4469.1±26.2±3.6 MeV/c^{2}, and 4675.3±29.5±3.5 MeV/c^{2} and widths of 81.6±17.8±9.0 MeV, 246.3±36.7±9.4 MeV, and 218.3±72.9±9.3 MeV, respectively, where the first uncertainties are statistical and the second systematic. The first and third resonances are consistent with the ψ(4230) and ψ(4660) states, respectively, while the second one is compatible with the ψ(4500) observed in the e^{+}e^{-}→K^{+}K^{-}J/ψ process. These three charmoniumlike ψ states are observed in the e^{+}e^{-}→D^{*0}D^{*-}π^{+} process for the first time.
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36
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Observation of e^{+}e^{-}→ωχ_{bJ}(1P) and Search for X_{b}→ωϒ(1S) at sqrt[s] near 10.75 GeV. PHYSICAL REVIEW LETTERS 2023; 130:091902. [PMID: 36930912 DOI: 10.1103/physrevlett.130.091902] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/29/2022] [Accepted: 01/25/2023] [Indexed: 06/18/2023]
Abstract
We study the processes e^{+}e^{-}→ωχ_{bJ}(1P) (J=0, 1, or 2) using samples at center-of-mass energies sqrt[s]=10.701, 10.745, and 10.805 GeV, corresponding to 1.6, 9.8, and 4.7 fb^{-1} of integrated luminosity, respectively. These data were collected with the Belle II detector during special operations of the SuperKEKB collider above the ϒ(4S) resonance. We report the first observation of ωχ_{bJ}(1P) signals at sqrt[s]=10.745 GeV. By combining Belle II data with Belle results at sqrt[s]=10.867 GeV, we find energy dependencies of the Born cross sections for e^{+}e^{-}→ωχ_{b1,b2}(1P) to be consistent with the shape of the ϒ(10753) state. These data indicate that the internal structures of the ϒ(10753) and ϒ(10860) states may differ. Including data at sqrt[s]=10.653 GeV, we also search for the bottomonium equivalent of the X(3872) state decaying into ωϒ(1S). No significant signal is observed for masses between 10.45 and 10.65 GeV/c^{2}.
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37
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Evidence for the Cusp Effect in η' Decays into ηπ^{0}π^{0}. PHYSICAL REVIEW LETTERS 2023; 130:081901. [PMID: 36898113 DOI: 10.1103/physrevlett.130.081901] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/06/2022] [Revised: 11/19/2022] [Accepted: 01/20/2023] [Indexed: 06/18/2023]
Abstract
Using a sample of 4.3×10^{5} η^{'}→ηπ^{0}π^{0} events selected from the ten billion J/ψ event dataset collected with the BESIII detector, we study the decay η^{'}→ηπ^{0}π^{0} within the framework of nonrelativistic effective field theory. Evidence for a structure at π^{+}π^{-} mass threshold is observed in the invariant mass spectrum of π^{0}π^{0} with a statistical significance of around 3.5σ, which is consistent with the cusp effect as predicted by the nonrelativistic effective field theory. After introducing the amplitude for describing the cusp effect, the ππ scattering length combination a_{0}-a_{2} is determined to be 0.226±0.060_{stat}±0.013_{syst}, which is in good agreement with theoretical calculation of 0.2644±0.0051.
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38
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Measurement of the Λ_{c}^{+} Lifetime. PHYSICAL REVIEW LETTERS 2023; 130:071802. [PMID: 36867815 DOI: 10.1103/physrevlett.130.071802] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/29/2022] [Accepted: 07/25/2022] [Indexed: 06/18/2023]
Abstract
An absolute measurement of the Λ_{c}^{+} lifetime is reported using Λ_{c}^{+}→pK^{-}π^{+} decays in events reconstructed from data collected by the Belle II experiment at the SuperKEKB asymmetric-energy electron-positron collider. The total integrated luminosity of the data sample, which was collected at center-of-mass energies at or near the ϒ(4S) resonance, is 207.2 fb^{-1}. The result, τ(Λ_{c}^{+})=203.20±0.89±0.77 fs, where the first uncertainty is statistical and the second systematic, is the most precise measurement to date and is consistent with previous determinations.
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39
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Search for a Dark Photon and an Invisible Dark Higgs Boson in μ^{+}μ^{-} and Missing Energy Final States with the Belle II Experiment. PHYSICAL REVIEW LETTERS 2023; 130:071804. [PMID: 36867830 DOI: 10.1103/physrevlett.130.071804] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/02/2022] [Accepted: 11/29/2022] [Indexed: 06/18/2023]
Abstract
The dark photon A^{'} and the dark Higgs boson h^{'} are hypothetical particles predicted in many dark sector models. We search for the simultaneous production of A^{'} and h^{'} in the dark Higgsstrahlung process e^{+}e^{-}→A^{'}h^{'} with A^{'}→μ^{+}μ^{-} and h^{'} invisible in electron-positron collisions at a center-of-mass energy of 10.58 GeV in data collected by the Belle II experiment in 2019. With an integrated luminosity of 8.34 fb^{-1}, we observe no evidence for signal. We obtain exclusion limits at 90% Bayesian credibility in the range of 1.7-5.0 fb on the cross section and in the range of 1.7×10^{-8}-200×10^{-8} on the effective coupling ϵ^{2}×α_{D} for the A^{'} mass in the range of 4.0 GeV/c^{2}<M_{A^{'}}<9.7 GeV/c^{2} and for the h^{'} mass M_{h^{'}}<M_{A^{'}}, where ϵ is the mixing strength between the standard model and the dark photon and α_{D} is the coupling of the dark photon to the dark Higgs boson. Our limits are the first in this mass range.
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Ruptured Sylvian arachnoid cysts: an update on a real problem. Childs Nerv Syst 2023; 39:93-119. [PMID: 36169701 PMCID: PMC9968703 DOI: 10.1007/s00381-022-05685-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/21/2022] [Accepted: 09/19/2022] [Indexed: 11/27/2022]
Abstract
PURPOSE Sylvian arachnoid cysts (SACs) are the most common type of arachnoid cysts and the most prone to undergo a rupture. This event is considered rare but potentially severe. No definite information is available on its occurrence or management. The goal of the present article is to provide an update on the epidemiological, etiological, and clinical aspects and the management of this peculiar clinical condition. METHODS A comprehensive review of the English literature of the last 40 years on this topic has been realized. Moreover, a personal series of children investigated and treated in the last 20 years is presented. These patients were managed as follows: (1) treatment of the subdural collection; (2) identification of candidates for surgical treatment of the residual cyst (brain MRI, perfusion brain MRI, prolonged invasive ICP monitoring (selected cases), EEG, neuropsychological tests); (3) surgical treatment of the cyst in the patients with pathological perfusion MRI and/or ICP measurement and/or clear neurophysiological and neuropsychological correlations. RESULTS A total of 446 patients (430 from the literature and 16 from the personal series), mainly children, adolescents, and young adults, have been analyzed leading to the following results: (1) SAC rupture is rare but not negligible (yearly risk of rupture: 0.04%; overall risk up to 10% in children affected by SCAs). Prophylactic surgery in asymptomatic cases is not advisable. (2) The mechanism of rupture is not known but an impact of SAC against the sphenoid wing and/or a direct injury on SAC through a thinned temporal bone, with possible laceration of the cyst wall vessels and/or tear of the bridging veins, can be hypothesized. A head injury is often not reported (may be misdiagnosed). (3) Subdural collection (hygroma > chronic hematoma) is the most common finding followed by intracystic bleeding, extradural hematoma, and other types of bleeding. Signs or symptoms of raised intracranial pressure are the most frequent ones. (4) The complication of the rupture is usually treated in emergency or in the acute period by burr hole or craniotomic evacuation of the subdural collection, although a conservative management is possible in some cases. Following the rupture, the majority of SACs are treated (70%), often at the same time of the complication, but no specific investigations are routinely performed to select candidates. According to our protocol, only 43.7% of SACs needed to be treated. CONCLUSIONS The "spontaneous" or posttraumatic rupture of SACs is a rare but potentially significant complication followed by a generally good outcome. The course of the cyst is independent from the outcome of the complication, consequently requiring specific investigations for individuating those lesions interfering with CSF dynamics and/or cerebral blood flow.
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The discovery of (1R, 3R)-1-(3-chloro-5-fluorophenyl)-3-(hydroxymethyl)-1,2,3,4-tetrahydroisoquinoline-6-carbonitrile, a potent and selective agonist of human transient receptor potential cation channel subfamily m member 5 (TRPM5) and evaluation of as a potential gastrointestinal prokinetic agent. Bioorg Med Chem 2022; 76:117084. [PMID: 36402081 DOI: 10.1016/j.bmc.2022.117084] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2022] [Revised: 10/31/2022] [Accepted: 11/01/2022] [Indexed: 11/08/2022]
Abstract
This publication details the discovery of a series of selective transient receptor potential cation channel subfamily M member 5 (TRPM5) agonists culminating with the identification of the lead compound (1R, 3R)-1-(3-chloro-5-fluorophenyl)-3-(hydroxymethyl)-1,2,3,4-tetrahydroisoquinoline-6-carbonitrile (39). We describe herein our biological rationale for agonism of the target, the examination of the then current literature tool molecules, and finally the process of our discovery starting with a high throughput screening hit through lead development. We also detail the selectivity of the lead compound 39 versus related family members TRPA1, TRPV1, TRPV4, TRPM4 and TRPM8, the drug metabolism and pharmacokinetics (DMPK) profile and in vivo efficacy in a mouse model of gastrointestinal motility.
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Study of the Semileptonic Decay Λ_{c}^{+}→Λe^{+}ν_{e}. PHYSICAL REVIEW LETTERS 2022; 129:231803. [PMID: 36563214 DOI: 10.1103/physrevlett.129.231803] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/28/2022] [Accepted: 11/01/2022] [Indexed: 06/17/2023]
Abstract
The study of the Cabibbo-favored semileptonic decay Λ_{c}^{+}→Λe^{+}ν_{e} is reported using a 4.5 fb^{-1} data sample of e^{+}e^{-} annihilations collected at center-of-mass energies ranging from 4.600 GeV to 4.699 GeV with the BESIII detector at the BEPCII collider. The branching fraction of the decay is measured to be B(Λ_{c}^{+}→Λe^{+}ν_{e})=(3.56±0.11_{stat}±0.07_{syst})%, which is the most precise measurement to date. Furthermore, we perform an investigation of the internal dynamics in Λ_{c}^{+}→Λe^{+}ν_{e}. We provide the first direct comparisons of the differential decay rate and form factors with those predicted from lattice quantum chromodynamics (LQCD) calculations. Combining the measured branching fraction with a q^{2}-integrated rate predicted by LQCD, we determine |V_{cs}|=0.936±0.017_{B}±0.024_{LQCD}±0.007_{τ_{Λ_{c}}}.
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Measurement of the Absolute Branching Fraction and Decay Asymmetry of Λ→nγ. PHYSICAL REVIEW LETTERS 2022; 129:212002. [PMID: 36461970 DOI: 10.1103/physrevlett.129.212002] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/23/2022] [Revised: 09/27/2022] [Accepted: 10/24/2022] [Indexed: 06/17/2023]
Abstract
The radiative hyperon decay Λ→nγ is studied using (10087±44)×10^{6} J/ψ events collected with the BESIII detector operating at BEPCII. The absolute branching fraction of the decay Λ→nγ is determined to be (0.832±0.038_{stat}±0.054_{syst})×10^{-3}, which is a factor of 2.1 lower and 5.6 standard deviations different than the previous measurement. By analyzing the joint angular distribution of the decay products, the first determination of the decay asymmetry α_{γ} is reported with a value of -0.16±0.10_{stat}±0.05_{syst}.
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Observation of an Isoscalar Resonance with Exotic J^{PC}=1^{-+} Quantum Numbers in J/ψ→γηη^{'}. PHYSICAL REVIEW LETTERS 2022; 129:192002. [PMID: 36399732 DOI: 10.1103/physrevlett.129.192002] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/03/2022] [Revised: 05/03/2022] [Accepted: 09/27/2022] [Indexed: 06/16/2023]
Abstract
Using a sample of (10.09±0.04)×10^{9} J/ψ events collected with the BESIII detector operating at the BEPCII storage ring, a partial wave analysis of the decay J/ψ→γηη^{'} is performed. The first observation of an isoscalar state with exotic quantum numbers J^{PC}=1^{-+}, denoted as η_{1}(1855), is reported in the process J/ψ→γη_{1}(1855) with η_{1}(1855)→ηη^{'}. Its mass and width are measured to be (1855±9_{-1}^{+6}) MeV/c^{2} and (188±18_{-8}^{+3}) MeV, respectively, where the first uncertainties are statistical and the second are systematic, and its statistical significance is estimated to be larger than 19σ.
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Observation of an a_{0}-like State with Mass of 1.817 GeV in the Study of D_{s}^{+}→K_{S}^{0}K^{+}π^{0} Decays. PHYSICAL REVIEW LETTERS 2022; 129:182001. [PMID: 36374689 DOI: 10.1103/physrevlett.129.182001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/24/2022] [Revised: 07/08/2022] [Accepted: 09/13/2022] [Indexed: 06/16/2023]
Abstract
Using e^{+}e^{-} annihilation data corresponding to an integrated luminosity of 6.32 fb^{-1} collected at center-of-mass energies between 4.178 and 4.226 GeV with the BESIII detector, we perform the first amplitude analysis of the decay D_{s}^{+}→K_{S}^{0}K^{+}π^{0} and determine the relative branching fractions and phases for intermediate processes. We observe an a_{0}-like state with mass of 1.817 GeV in its decay to K_{S}^{0}K^{+} for the first time. In addition, we measure the ratio {B[D_{s}^{+}→K[over ¯]^{*}(892)^{0}K^{+}]/B[D_{s}^{+}→K[over ¯]^{0}K^{*}(892)^{+}]} to be 2.35_{-0.23stat}^{+0.42}±0.10_{syst}. Finally, we provide a precision measurement of the absolute branching fraction B(D_{s}^{+}→K_{S}^{0}K^{+}π^{0})=(1.46±0.06_{stat}±0.05_{syst})%.
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Precise Measurements of Decay Parameters and CP Asymmetry with Entangled Λ-Λ[over ¯] Pairs. PHYSICAL REVIEW LETTERS 2022; 129:131801. [PMID: 36206435 DOI: 10.1103/physrevlett.129.131801] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/26/2022] [Accepted: 09/01/2022] [Indexed: 06/16/2023]
Abstract
Based on 10 billion J/ψ events collected at the BESIII experiment, a search for CP violation in Λ decay is performed in the difference between CP-odd decay parameters α_{-} for Λ→pπ^{-} and α_{+} for Λ[over ¯]→p[over ¯]π^{+} by using the process e^{+}e^{-}→J/ψ→ΛΛ[over ¯]. With a five-dimensional fit to the full angular distributions of the daughter baryon, the most precise values for the decay parameters are determined to be α_{-}=0.7519±0.0036±0.0024 and α_{+}=-0.7559±0.0036±0.0030, respectively. The Λ and Λ[over ¯] averaged value of the decay parameter is extracted to be α_{avg}=0.7542±0.0010±0.0024 with unprecedented accuracy. The CP asymmetry A_{CP}=(α_{-}+α_{+})/(α_{-}-α_{+}) is determined to be -0.0025±0.0046±0.0012, which is one of the most precise measurements in the baryon sector. The reported results for the decay parameter will play an important role in the studies of the polarizations and CP violations for the strange, charmed and beauty baryons.
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First Observation of the Direct Production of the χ_{c1} in e^{+}e^{-} Annihilation. PHYSICAL REVIEW LETTERS 2022; 129:122001. [PMID: 36179210 DOI: 10.1103/physrevlett.129.122001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/23/2022] [Revised: 06/22/2022] [Accepted: 07/26/2022] [Indexed: 06/16/2023]
Abstract
We study the direct production of the J^{PC}=1^{++} charmonium state χ_{c1}(1P) in electron-positron annihilation by carrying out an energy scan around the mass of the χ_{c1}(1P). The data were collected with the BESIII detector at the BEPCII collider. An interference pattern between the signal process e^{+}e^{-}→χ_{c1}(1P)→γJ/ψ→γμ^{+}μ^{-} and the background processes e^{+}e^{-}→γ_{ISR}J/ψ→γ_{ISR}μ^{+}μ^{-} and e^{+}e^{-}→γ_{ISR}μ^{+}μ^{-} is observed by combining all the data samples. The χ_{c1}(1P) signal is observed with a significance of 5.1σ. This is the first observation of a C-even state directly produced in e^{+}e^{-} annihilation. The electronic width of the χ_{c1}(1P) resonance is determined to be Γ_{ee}=(0.12_{-0.08}^{+0.13}) eV, which is of the same order of magnitude as theoretical calculations.
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Evidence for a Neutral Near-Threshold Structure in the K_{S}^{0} Recoil-Mass Spectra in e^{+}e^{-}→K_{S}^{0}D_{s}^{+}D^{*-} and e^{+}e^{-}→K_{S}^{0}D_{s}^{*+}D^{-}. PHYSICAL REVIEW LETTERS 2022; 129:112003. [PMID: 36154413 DOI: 10.1103/physrevlett.129.112003] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/26/2022] [Revised: 06/17/2022] [Accepted: 06/30/2022] [Indexed: 06/16/2023]
Abstract
We study the processes e^{+}e^{-}→K_{S}^{0}D_{s}^{+}D^{*-} and e^{+}e^{-}→K_{S}^{0}D_{s}^{*+}D^{-}, as well as their charge conjugated processes, at five center-of-mass energies between 4.628 and 4.699 GeV, using data samples corresponding to an integrated luminosity of 3.8 fb^{-1} collected by the BESIII detector at the BEPCII storage ring. Based on a partial reconstruction technique, we find evidence of a structure near the thresholds for D_{s}^{+}D^{*-} and D_{s}^{*+}D^{-} production in the K_{S}^{0} recoil-mass spectrum, which we refer to as the Z_{cs}(3985)^{0}. Fitting with a Breit-Wigner line shape, we find the mass of the structure to be (3992.2±1.7±1.6) MeV/c^{2} and the width to be (7.7_{-3.8}^{+4.1}±4.3) MeV, where the first uncertainties are statistical and the second are systematic. The significance of the Z_{cs}(3985)^{0} signal is found to be 4.6σ including both the statistical and systematic uncertainty. We report the Born cross section multiplied by the branching fraction at different energy points. The mass of the Z_{cs}(3985)^{0} is close to that of the Z_{cs}(3985)^{+}. Assuming SU(3) symmetry, the cross section of the neutral channel is consistent with that of the charged one. Hence, we conclude that the Z_{cs}(3985)^{0} is the isospin partner of the Z_{cs}(3985)^{+}.
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Observation of Resonance Structures in e^{+}e^{-}→π^{+}π^{-}ψ_{2}(3823) and Mass Measurement of ψ_{2}(3823). PHYSICAL REVIEW LETTERS 2022; 129:102003. [PMID: 36112441 DOI: 10.1103/physrevlett.129.102003] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/11/2022] [Revised: 07/21/2022] [Accepted: 08/09/2022] [Indexed: 06/15/2023]
Abstract
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 measure the product of the e^{+}e^{-}→π^{+}π^{-}ψ_{2}(3823) cross section and the branching fraction B[ψ_{2}(3823)→γχ_{c1}]. For the first time, resonance structure is observed in the cross section line shape of e^{+}e^{-}→π^{+}π^{-}ψ_{2}(3823) with significances exceeding 5σ. A fit to data with two coherent Breit-Wigner resonances modeling the sqrt[s]-dependent cross section yields M(R_{1})=4406.9±17.2±4.5 MeV/c^{2}, Γ(R_{1})=128.1±37.2±2.3 MeV, and M(R_{2})=4647.9±8.6±0.8 MeV/c^{2}, Γ(R_{2})=33.1±18.6±4.1 MeV. Though weakly disfavored by the data, a single resonance with M(R)=4417.5±26.2±3.5 MeV/c^{2}, Γ(R)=245±48±13 MeV is also possible to interpret data. This observation deepens our understanding of the nature of the vector charmoniumlike states. The mass of the ψ_{2}(3823) state is measured as (3823.12±0.43±0.13) MeV/c^{2}, which is the most precise measurement to date.
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Ultra-sensitive solid-phase Microextraction-Gas Chromatography-Mass spectrometry determination of polycyclic aromatic hydrocarbons in snow samples using a deep cavity BenzoQxCavitand. CHEMOSPHERE 2022; 303:135144. [PMID: 35660393 DOI: 10.1016/j.chemosphere.2022.135144] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/20/2022] [Revised: 05/04/2022] [Accepted: 05/25/2022] [Indexed: 05/26/2023]
Abstract
A very sensitive and selective solid-phase microextraction-gas chromatography-mass spectrometry method based on the use of a deep cavity BenzoQxCavitand as innovative coating was developed and validated for the simultaneous determination of the 16 US-EPA priority pollutants polycyclic aromatic hydrocarbons (PAHs) in snow samples at ultra-trace levels. The presence of a 8.3 Å deep hydrophobic cavity allowed the engulfment of all the 16 PAHs, providing enhanced selectivity also in presence of interfering aromatic pollutants at high concentration levels. Validation proved the reliability of the method for the determination of the investigated compounds achieving detection limits in the 0.03-0.30 ng/L range, good precision, with relative standard deviations <18% and recovery rates in the 90.8(±2.1)%-109.6(±1.0)%. The detection of low-molecular weight PAHs in snow samples from Antarctica and Alps confirms the widespread occurrence of these compounds, thus assessing the impact of anthropogenic activities onto the environment.
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