| 11. |
- Ablikim, M., et al.
(författare)
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Measurement of chi(cJ) decaying into eta ' K+K-
- 2014
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Ingår i: Physical Review D. - 1550-7998 .- 1550-2368. ; 89:7, s. 074030-
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Tidskriftsartikel (refereegranskat)abstract
- Using (106.41 +/- 0.86) x 10(6) Psi(3686) events collected with the BESIII detector at BEPCII, we study for the first time the decay chi(cJ) -> eta'K+K- (J = 1, 2), where eta' -> gamma rho(0) and eta' -> eta pi(+)pi(-). A partial wave analysis in the covariant tensor amplitude formalism is performed for the decay chi(c1) -> eta'K+K-. Intermediate processes chi(c1) -> eta'f(2)'(1525) chi(c1) -> K-0*(1430)K-+/-(-/+) (K-0*(1430)(+/-) -> eta'K-+/-) are observed with statistical significances larger than 5 sigma, and their branching fractions are measured.
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| 12. |
- Ablikim, M., et al.
(författare)
-
Measurement of cross sections of the interactions e(+)e(-) -> phi phi omega and e(+)e(-) -> phi phi phi at center-of-mass energies from 4.008 to 4.600 GeV
- 2017
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Ingår i: Physics Letters B. - : Elsevier BV. - 0370-2693 .- 1873-2445. ; 774, s. 78-86
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Tidskriftsartikel (refereegranskat)abstract
- Using data samples collected with the BESIII detector at the BEPCII collider at six center-of-mass energies between 4.008 and 4.600 GeV, we observe the processes e(+)e(-) -> phi phi omega and e(-)e(-) -> phi phi phi. The Born cross sections are measured and the ratio of the cross sections sigma(e(+)e(-) -> phi phi omega)/sigma(e(-)e(-) -> phi phi phi) is estimated to be 1.75 +/- 0.22 +/- 0.19 averaged over six energy points, where the first uncertainty is statistical and the second is systematic. The results represent first measurements of these interactions.
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| 13. |
- Ablikim, M., et al.
(författare)
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Measurement of e(+)e(-) -> K(K)over-barJ/psi cross sections at center-of-mass energies from 4.189 to 4.600 GeV
- 2018
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Ingår i: Physical Review D. - : AMER PHYSICAL SOC. - 2470-0010 .- 2470-0029. ; 97:7
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Tidskriftsartikel (refereegranskat)abstract
- We investigate the process e(+)e(-) -> K (K) over barJ/psi at center-of-mass energies from 4.189 to 4.600 GeV using 4.7 fb(-1) of data collected by the BESIII detector at the BEPCII collider. The Born cross sections for the reactions e(+)e(-) -> K(+)K(-)J/psi and K(S)(0)K(S)(0)J/psi are measured as a function of center-of-mass energy. The energy dependence of the cross section for e(+)e(-) -> K(+)K(-)J/psi is shown to differ from that for pi(+)pi(-)J/psi in the region around the Y(4260). In addition, there is evidence for a structure around 4.5 GeV in the e(+)e(-) -> K(+)K(-)J/psi cross section that is not present in pi(+)pi(-)J/psi.
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| 14. |
- Ablikim, M., et al.
(författare)
-
Measurement of e(+)e(-) -> pi(+)pi(-) psi(3686) from 4.008 to 4.600 GeV and observation of a charged structure in the pi(+/-)psi(3686) mass spectrum
- 2017
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Ingår i: Physical Review D. - 2470-0010 .- 2470-0029. ; 96:3
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Tidskriftsartikel (refereegranskat)abstract
- We study the process e(+)e(-) -> p(+)p(-)psi(3686) using 5.1 fb(-1) of data collected at 16 center-of-mass energy (root s) points from 4.008 to 4.600 GeV by the BESIII detector operating at the BEPCII collider. The measured Born cross sections for e(+)e(-) -> p(+)p(-)psi(3686) are consistent with previous results, but with much improved precision. A fit to the cross section shows contributions from two structures: the first has M = 4209.5 +/- 7.4 +/- 1.4 MeV/c(2) and Gamma = 80.1 +/- 24.6 +/- 2.9 MeV, and the second has M = 4383.8 +/- 4.2 +/- 0.8 MeV/c(2) and Gamma = 84.2 +/- 12.5 +/- 2.1 MeV, where the first errors are statistical and the second systematic. The lower-mass resonance is observed in the process e(+)e(-) -> p(+)p(-)psi(3686) for the first time with a statistical significance of 5.8 sigma. A charged charmoniumlike structure is observed in the pi(+/-)psi(3686) invariant mass spectrum for data at root s = 4.416 GeV. A fit with an S-wave Breit-Wigner function yields a mass M = 4032.1 +/- 2.4 MeV/c(2), where the errors are statistical only. However, there are still unresolved discrepancies between the fit model and data. The width of the intermediate state varies in a wide range for different kinematic regions within the data set. Therefore, no simple interpretation of the data has been found, and a future data sample with larger statistics and more theoretical input will be required to better understand this issue.
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| 15. |
- Ablikim, M., et al.
(författare)
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Measurement of integrated luminosity and center-of-mass energy of data taken by BESIII at √s=2.125 GeV
- 2017
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Ingår i: Chinese Physics C. - : IOP Publishing. - 1674-1137 .- 2058-6132. ; 41:11
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Tidskriftsartikel (refereegranskat)abstract
- To study the nature of the state Y (2175), a dedicated data set of e(+)e(-) collision data was collected at the center-of-mass energy of 2.125 GeV with the BESIII detector at the BEPCII collider. By analyzing large-angle Bhabha scattering events, the integrated luminosity of this data set is determined to be 108.49 +/- 0.02 +/- 0.85 pb(-1), where the first uncertainty is statistical and the second one is systematic. In addition, the center-of-mass energy of the data set is determined with radiative dimuon events to be 2126.55 +/- 0.03 +/- 0.85 MeV, where the first uncertainty is statistical and the second one is systematic.
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| 16. |
- Ablikim, M., et al.
(författare)
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Measurement of Singly Cabibbo Suppressed Decays Lambda(+)(c) -> p pi(+)pi(-) and Lambda(+)(c) -> pK(+)K(-)
- 2016
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Ingår i: Physical Review Letters. - 0031-9007 .- 1079-7114. ; 117:23
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Tidskriftsartikel (refereegranskat)abstract
- Using 567 pb(-1) of data collected with the BESIII detector at a center-of-mass energy of root s = 4.599 GeV, near the Lambda(+)(c)->(Lambda) over bar (-)(c) threshold, we study the singly Cabibbo-suppressed decays Lambda c(+) -> p pi(+) pi(-) and Lambda(+)(c) -> pK(+) K- By normalizing with respect to the Cabibbo-favored decay Lambda(+)(c)-> p pi(+)pi(-) we obtain ratios of branching fractions: [B(Lambda(+)(c) -> p pi(+)pi(-))/B(Lambda(+)(c) -> pK(-)pi(+))] = (6.70 +/- 0.48 +/- 0.25)% [B Lambda(+)(c) -> p phi)/B(Lambda(+)(c) -> pK(-)pi(+))] = (1.81 +/- 0.33 +/- 0.13)%,and [B(Lambda(+)(c) -> pK(+)K(non-phi)(-)/B(Lambda(+)(c) -> pK(-)pi(+))] (9.36 +/- 2.22 +/- 0.71)x10(-3), where the uncertainties are statistical and systematic, respectively. The absolute branching fractions are also presented. Among these measurements, the decay Lambda(+)(c) -> p pi(+)pi(-) is observed for the first time, and the precision of the branching fraction for Lambda(+)(c) -> pK(+)K(non-phi)(-) and Lambda(+)(c) -> p phi is significantly improved.
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| 17. |
- Ablikim, M., et al.
(författare)
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Measurement of the absolute branching fraction of D*(s0) (2317)(+/-) -> pi D-0(s)+/-
- 2018
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Ingår i: Physical Review D. - : American Physical Society. - 2470-0010 .- 2470-0029. ; 97:5
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Tidskriftsartikel (refereegranskat)abstract
- The process e(+)e(-) -> D*D-+(s)*(s0) (2317)(-) + c.c. is observed for the first time with the data sample of 567 pb(-1) collected with the BESIII detector operating at the BEPCII collider at a center-of-mass energy root s = 4.6 GeV. The statistical significance of the D*(s0) (2317)(+/-) signal is 5.8 sigma and the mass is measured to be (2318.3 +/- 1.2 +/- 1.2) MeV/c(2). The absolute branching fraction B(D*(s0) (2317)(+/-) -> pi D-0(s)+/-) is measured as 1.00(-0.14)(+0.00) (stat)(-0.14)(+0.00) (syst) for the first time. The uncertainties are statistical and systematic, respectively.
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| 18. |
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| 19. |
- Ablikim, M., et al.
(författare)
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Measurement of the proton form factor by studying e(+)e(-) -> p(p)over-tilde
- 2015
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Ingår i: Physical Review D. - 1550-7998 .- 1550-2368. ; 91:11
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Tidskriftsartikel (refereegranskat)abstract
- Using data samples collected with the BESIII detector at the BEPCII collider, we measure the Born cross section of e(+)e(-) -> p (p) over tilde at 12 center-of-mass energies from 2232.4 to 3671.0 MeV. The corresponding effective electromagnetic form factor of the proton is deduced under the assumption that the electric and magnetic form factors are equal (vertical bar G(E)vertical bar = vertical bar G(M)vertical bar). In addition, the ratio of electric to magnetic form factors, vertical bar G(E)/G(M)vertical bar, and vertical bar G(M)vertical bar are extracted by fitting the polar angle distribution of the proton for the data samples with larger statistics, namely at root s = 2232.4 and 2400.0 MeV and a combined sample at root s = 3050.0, 3060.0 and 3080.0 MeV, respectively. The measured cross sections are in agreement with recent results from BABAR, improving the overall uncertainty by about 30%. The vertical bar G(E)/G(M)vertical bar ratios are close to unity and consistent with BABAR results in the same q(2) region, which indicates the data are consistent with the assumption that vertical bar G(E)vertical bar = vertical bar G(M)vertical bar within uncertainties.
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| 20. |
- Ablikim, M., et al.
(författare)
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Measurements of cross section of e(+)e(-) -> p(p)over-bar pi(0) at center-of-mass energies between 4.008 and 4.600 GeV
- 2017
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Ingår i: Physics Letters B. - : ELSEVIER SCIENCE BV. - 0370-2693 .- 1873-2445. ; 771, s. 45-51
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Tidskriftsartikel (refereegranskat)abstract
- Based on e(+)e(-) annihilation data samples collected with the BESIII detector at the BEPCII collider at 13 center-of-mass energies from 4.008 to 4.600 GeV, measurements of the Born cross section of e(+)e(-) -> p (p) over bar pi(0) are performed. No significant resonant structure is observed in the measured energy dependence of the cross section. The upper limit on the Born cross section of e(+)e(-) -> Y (4260) -> p (p) over bar pi(0) at the 90% C. L. is determined to be 0.01 pb. The upper limit on the ratio of the branching fractions B(Y(4260) -> p (p) over bar pi(0))/B(Y(4260) -> pi(+)pi(-) j/Psi) at the 90% C. L. is determined to be 0.02%.
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