| 1. |
- Ablikim, M., et al.
(författare)
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Amplitude analysis and branching fraction measurement of D-0 -> K-pi(+)pi(0)pi(0)
- 2019
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Ingår i: Physical Review D. - : American Physical Society. - 2470-0010 .- 2470-0029. ; 99:9
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Tidskriftsartikel (refereegranskat)abstract
- Utilizing the dataset corresponding to an integrated luminosity of 2.93 fb(-1) at root s = 3.773 GeV collected by the BESIII detector, we report the first amplitude analysis and branching fraction measurement of the D-0 -> K- pi(+)pi(0)pi(0) decay. We investigate the substructures and determine the relative fractions and the phases among the different intermediate processes. Our results are used to provide an accurate detection efficiency and allow measurement of B(D-0 -> K- pi(+)pi(0)pi(0)) = (8.86 +/- 0.13(stat) +/- 0.19(syst))%.
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| 2. |
- Ablikim, M., et al.
(författare)
-
Amplitude analysis of D+-> K-S(0)pi(+)pi(+)pi(-)
- 2019
-
Ingår i: Physical Review D. - : AMER PHYSICAL SOC. - 2470-0010 .- 2470-0029. ; 100:7
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Tidskriftsartikel (refereegranskat)abstract
- The decay D+-> K-S(0)pi(+)pi(+)pi(-) is studied with an amplitude analysis using a data set of 2.93 fb(-1) of e(+)e(-) collisions at the psi(3770) peak accumulated by the BESIII detector. Intermediate states and nonresonant components, and their relative fractions and phases, have been determined. The significant amplitudes, which contribute to the model that best fits the data, are composed of five quasitwo-body decays K(S)(0)a(1)(1260)(+), (K) over bar (1)(1270)(0)pi(+) (K) over bar (1)(1400)(0)pi(+), (K) over bar (1)(1650)(0)pi(+), and (K) over bar (1460)(0)pi(+), a three-body decay K-S(0)pi(+)rho(0), as well as a nonresonant component K-S(0)pi(+)pi(+)pi(-). The dominant amplitude is K(S)(0)a(1)(1260)(+), with a fit fraction of (40.3 +/- 2.1 +/- 2.9)%, where the first and second uncertainties are statistical and systematic, respectively.
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| 3. |
- Ablikim, M., et al.
(författare)
-
Amplitude Analysis of D-s(+) -> pi(+)pi(0)eta and First Observation of the W-Annihilation Dominant Decays D-s(+) -> a(0)(980)(+)pi(0) and D-s(+) -> a(0)(980)(0)pi(+)
- 2019
-
Ingår i: Physical Review Letters. - : AMER PHYSICAL SOC. - 0031-9007 .- 1079-7114. ; 123:11
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Tidskriftsartikel (refereegranskat)abstract
- We present the first amplitude analysis of the decay D-s(+) -> pi(+)pi(0)eta. We use an e(+)e(-) collision data sample corresponding to an integrated luminosity of 3.19 fb(-1) collected with the BESIII detector at a center-of-mass energy of 4.178 GeV. We observe for the first time the W-annihilation dominant decays D-s(+) -> a(0)(980)(+)pi(0) and D-s(+) -> a(0)(980)(0)pi(+). We measure the absolute branching fraction B(D-s(+) -> a(0)(980)(+(0))pi(0(+)), a(0)(980)(+(0)) -> pi(+(0)())eta = (1.46 +/- 0.15(stat )+/- 0.23 sys)%, which is larger than the branching fractions of other measured pure W-annihilation decays by at least one order of magnitude. In addition, we measure the branching fraction of D-s(+) -> pi(+)pi(0)eta with significantly improved precision.
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| 4. |
- Ablikim, M., et al.
(författare)
-
Complete Measurement of the Λ Electromagnetic Form Factors
- 2019
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Ingår i: Physical Review Letters. - 0031-9007 .- 1079-7114. ; 123:12
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Tidskriftsartikel (refereegranskat)abstract
- The exclusive process e(+)e(-) -> Lambda(Lambda) over bar, with Lambda -> p pi(-) and (Lambda) over bar -> (p) over bar pi(+), has been studied at root s = 2.396 GeV for measurement of the timelike Lambda electric and magnetic form factors, G(E) and G(M). A data sample, corresponding to an integrated luminosity of 66.9 pb(-1), was collected with the BESIII detector for this purpose. A multidimensional analysis with a complete decomposition of the spin structure of the reaction enables a determination of the modulus of the ratio R = vertical bar G(E)/G(M)vertical bar and, for the first time for any baryon, the relative phase Delta Phi = Phi(E) - Phi(M). The resulting values are R = 0.96 +/- 0.14(stat) +/- 0.02(syst) and Phi(F) = 37 degrees +/- 12 degrees (stat) +/- 6 degrees (syst), respectively. These are obtained using the recently established and most precise value of the asymmetry parameter alpha(Lambda) = 0.750 +/- 0.010 measured by BESIII. In addition, the cross section is measured with unprecedented precision to be sigma = 118.7 +/- 5.3(stat) +/- 5.1(syst) pb, which corresponds to an effective form factor of vertical bar G vertical bar = 0.123 +/- 0.003(stat) +/- 0.003(syst). The contribution from two-photon exchange is found to be negligible. Our result enables the first complete determination of baryon timelike electromagnetic form factors.
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| 5. |
- Ablikim, M., et al.
(författare)
-
Cross section measurements of e+e- -> K+ K- K+ K- and ΦK+ K- at center-of-mass energies from 2.10 to 3.08 GeV
- 2019
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Ingår i: Physical Review D. - 2470-0010 .- 2470-0029. ; 100:3
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Tidskriftsartikel (refereegranskat)abstract
- We measure the Born cross sections of the process e(+)e(-) -> K+ K- K+ K- at center-of-mass (c.m.) energies, root s, between 2.100 and 3.080 GeV. The data were collected using the BESIII detector at the BEPCII collider. An enhancement at root s = 2.232 GeV is observed, very close to the e(+)e(-) -> Lambda(Lambda) over bar production threshold. A similar enhancement at the same c.m. energy is observed in the e(+)e(-) -> phi K+ K- cross section. The energy dependence of the K+ K- K+ K- and phi K+ K- cross sections differs significantly from that of e(+)e(-) -> phi pi(+)pi(-).
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| 6. |
- Ablikim, M., et al.
(författare)
-
Cross section measurements of e(+) e(-) -> omega chi(c0) from root s=4.178 to 4.278 GeV
- 2019
-
Ingår i: Physical Review D. - : AMER PHYSICAL SOC. - 2470-0010 .- 2470-0029. ; 99:9
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Tidskriftsartikel (refereegranskat)abstract
- The cross section of the process e(+)e(-) -> omega chi(C0) is measured at center -of -mass energies from root s = 4.178 to 4.278 GeV using a data sample of 7 fb(-1) collected with the BESIII detector operating at the BEPCII storage ring. The dependence of the cross section on root s shows a resonant structure with mass of (4218.5 +/- 1.6(stat) +/- 4.0(syst)) MeV/c(2) and width of (28.2 +/- 3.9(stat) +/- 1.6(syst)) MeV, respectively. This observation confirms and improves upon the result of a previous study. The angular distribution of the e(+) e(-) ->omega chi(C0) process is extracted for the first time.
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| 7. |
- Ablikim, M., et al.
(författare)
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Determination of the Pseudoscalar Decay Constant f(Ds)(+) via D-s(+) -> mu(+)nu(mu)
- 2019
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Ingår i: Physical Review Letters. - : AMER PHYSICAL SOC. - 0031-9007 .- 1079-7114. ; 122:7
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Tidskriftsartikel (refereegranskat)abstract
- Using a 3.19 fb(-1) data sample collected at an e(+)e(-) center-of-mass energy of E-cm = 4.178 GeV with the BESIII detector, we measure the branching fraction of the leptonic decay D-s(+) -> mu(+)nu(mu) to be BDs+ -> mu+nu mu = (5.49 +/- 0.16(stat) +/- 0.15(syst)) x 10(-3). Combining our branching fraction with the masses of the D-s(+) and mu(+) and the lifetime of the D-s(+), we determine f(Ds+)vertical bar V-cs vertical bar = 246.2 +/- 3.6(stat) +/- 3.5(syst) MeV. Using the c -> s quark mixing matrix element vertical bar V-cs vertical bar determined from a global standard model fit, we evaluate the D-s(+) decay constant f(Ds+) = 252.9 +/- 3.7(stat) +/- 3.6(syst) MeV. Alternatively, using the value of f(Ds+) calculated by lattice quantum chromodynamics, we find vertical bar V-cs vertical bar = 0.985 +/- 0.014(stat) +/- 0.014(syst). These values of BDs+ -> mu+nu mu, f(Ds+)vertical bar V-cs vertical bar, f(Ds+) and vertical bar V-cs vertical bar are each the most precise results to date.
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| 8. |
- Ablikim, M., et al.
(författare)
-
Evidence for the decays of Lambda(+)(C) -> Sigma(+) eta and Sigma(+) eta '
- 2019
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Ingår i: Chinese Physics C. - : IOP PUBLISHING LTD. - 1674-1137 .- 2058-6132. ; 43:8
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Tidskriftsartikel (refereegranskat)abstract
- We study the hadronic decays of Lambda(+)(C) to the final states Sigma(+) eta and Sigma(+) eta', using an e(+) e(-) annihilation data sample of 567 pb(-1) taken at a center-of-mass energy of 4.6 GeV with the BESIII detector at the BEPCII collider. We find evidence for the decays Lambda(+)(C) -> Sigma(+) eta and Sigma(+) eta' with statistical significance of and, respectively. Normalizing to the reference decays Lambda(+)(C) -> Sigma(+) pi(0) and Sigma(+) omega, we obtain the ratios of the branching fractions B(Lambda(+)(C) -> Sigma(+) eta)/B(Lambda(+)(C) -> Sigma(+) pi(0)) and B(Lambda(+)(C) -> Sigma(+) eta')/B(Lambda(+)(C) -> Sigma(+) omega) to be 0.35 +/- 0.16 +/- 0.02 and 0.86 +/- 0.34 +/- 0.04, respectively. The upper limits at the 90% confidence level are set to be B(Lambda(+)(C) -> Sigma(+) eta)/B(Lambda(+)(C) -> Sigma(+) pi(0)) < 0.58 and B(Lambda(+)(C) -> Sigma(+) eta')/B(Lambda(+)(C) -> Sigma(+) omega) < 1.2. Using BESIII measurements of the branching fractions of the reference decays, we determine B(Lambda(+)(C) -> Sigma(+) eta) = (0.41 +/- 0.19 +/- 0.05)% (<0.68%) and B(Lambda(+)(C) -> Sigma(+) eta') = (1.34 +/- 0.53 +/- 0.19)% (<1.9%). Here, the first uncertainties are statistical and the second systematic. The obtained branching fraction of Lambda(+)(C) -> Sigma(+) eta is consistent with the previous measurement, and the branching fraction of Lambda(+)(C) -> Sigma(+) eta' is measured for the first time.
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| 9. |
- Ablikim, M., et al.
(författare)
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Evidence of a Resonant Structure in the e(+) e(-) -> pi(+) (DD)-D-0*(-) Cross Section between 4.05 and 4.60 GeV
- 2019
-
Ingår i: Physical Review Letters. - 0031-9007 .- 1079-7114. ; 122:10
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Tidskriftsartikel (refereegranskat)abstract
- The cross section of the process e(+) e(-) -> pi(+) (DD)-D-0*(-) for center-of-mass energies from 4.05 to 4.60 GeV is measured precisely using data samples collected with the BESIII detector operating at the BEPCII storage ring. Two enhancements are clearly visible in the cross section around 4.23 and 4.40 GeV. Using several models to describe the dressed cross section yields stable parameters for the first enhancement, which has a mass of 4228.6 +/- 4.1 +/- 6.3 MeV/c(2) and a width of 77.0 +/- 6.8 +/- 6.3 MeV, where the first uncertainties are statistical and the second ones are systematic. Our resonant mass is consistent with previous observations of the Y(4220) state and the theoretical prediction of a D (D) over bar (1)(2420) molecule. This result is the first observation of Y(4220) associated with an open-charm final state. Fits with three resonance functions with additional Y(4260), Y(4320), Y(4360), psi(4415), or a new resonance do not show significant contributions from either of these resonances. The second enhancement is not from a single known resonance. It could contain contributions from psi(4415) and other resonances, and a detailed amplitude analysis is required to better understand this enhancement.
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| 10. |
- Ablikim, M., et al.
(författare)
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First Measurement of the Form Factors in D-s(+) -> K(0)e(+)nu(e) and D-s(+) -> K*(0)e(+)nu(e) Decays
- 2019
-
Ingår i: Physical Review Letters. - : AMER PHYSICAL SOC. - 0031-9007 .- 1079-7114. ; 122:6
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Tidskriftsartikel (refereegranskat)abstract
- We report on new measurements of Cabibbo-suppressed semileptonic D-s(broken vertical bar) decays using 3.19 fb(-1) of e(broken vertical bar)e(-) annihilation data sample collected at a center-of-mass energy of 4.178 GeV with the BESIII detector at the BEPCII collider. Our results include branching fractions B(D-s(+) -> K(0)e(+)nu(e)) = [3.25 +/- 0.38(stat) +/- 0.16(syst)] x 10(-3) and B(D-s(+) -> K*(0)e(+)nu(e)) = [2.37 +/- 0.26(stat) +/- 0.20(syst)] x 10(-3), which are much improved relative to previous measurements, and the first measurements of the hadronic form-factor parameters for these decays. For D-s(+) -> K(0)e(+)nu(e), we obtain f(+)(0) = 0.720 +/- 0.084(stat) +/- 0.013(syst), and for D-s(+) -> K*(0)e(+)nu(e), we find form-factor ratios r(V) = V(0)/A(1)(0) = 1.67 +/- 0.34(stat) +/- 0.16(syst) and r(2) = A(2)(0)/A(1)(0) = 0.77 +/- 0.28(stat) +/- 0.07(syst).
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