| 1. |
- Ablikim, M., et al.
(author)
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Measurement of the integrated Luminosities of cross-section scan data samples around the psi(3770) mass region
- 2018
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In: Chinese Physics C. - : SCIENCE PRESS. - 1674-1137 .- 2058-6132. ; 42:6
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Journal article (peer-reviewed)abstract
- To investigate the nature of the psi(3770) resonance and to measure the cross section for e(+)e(-) -> D (D) over bar, a cross-section scan data sample, distributed among 41 center-of-mass energy points from 3.73 to 3.89 GeV, was taken with the BESIII detector operated at the BEPCII collider in the year 2010. By analyzing the large angle Bhabha scattering events, we measure the integrated luminosity of the data sample at each center-of-mass energy point. The total integrated luminosity of the data sample is 76.16 +/- 0.04 +/- 0.61 pb(-1), where the first uncertainty is statistical and the second systematic.
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| 2. |
- Ablikim, M., et al.
(author)
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Measurement of e(+)e(-) -> D(D)over-bar cross sections at the psi(3770) resonance
- 2018
-
In: Chinese Physics C. - : IOP PUBLISHING LTD. - 1674-1137 .- 2058-6132. ; 42:8
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Journal article (peer-reviewed)abstract
- We report new measurements of the cross sections for the production of D (D) over bar final states at the psi(3770) resonance. Our data sample consists of an integrated luminosity of 2.93 fb(-1) of e(+)e(-) annihilation data produced by the BEPCII collider and collected and analyzed with the BESIII detector. We exclusively reconstruct three D-0 and six D+ hadronic decay modes and use the ratio of the yield of fully reconstructed D (D) over bar events ("double tags") to the yield of all reconstructed D or (D) over bar mesons ("single tags") to determine the number of D-0(D) over bar (0) and D+D- events, benefiting from the cancellation of many systematic uncertainties. Combining these yields with an independent determination of the integrated luminosity of the data sample, we find the cross sections to be sigma(e(+)e(-) -> D-0(D) over bar (0)(-) )=(3.615 +/- 0.010 +/- 0.038) nb and sigma(e(+)e(-) -> D+D-)=(2.830 +/- 0.011 +/- 0.026) nb, where the uncertainties are statistical and systematic, respectively.
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| 3. |
- Ablikim, M., et al.
(author)
-
Observation of the Semileptonic Decay D-0 -> a(0)(980)(-)e(+)nu(e) and Evidence for D+ -> a(0)(980)(0)e(+)nu(e)
- 2018
-
In: Physical Review Letters. - : AMER PHYSICAL SOC. - 0031-9007 .- 1079-7114. ; 121:8
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Journal article (peer-reviewed)abstract
- Using an e(+)e(-) collision data sample of 2.93 fb(-1) collected at a center-of-mass energy of 3.773 GeV by the BESIII detector at BEPCII, we report the observation of D-0 -> a(0)(980)(-)e(+)nu(e) and evidence for D+ -> a(0)(980)(0)e(+)nu(e) with significances of 6.4 sigma and 2.9 sigma, respectively. The absolute branching fractions are determined to be B(D-0 -> a(0)(980)(-)e(+)nu(e)) x B(a(0)(980)(-) -> eta pi(-)) = [1.33(-0.29)(+0.33)(stat) +/- 0.09(syst)] x 10(-4) and B(D+ -> a(0)(980)(0)e(+)nu(e)) x B(a(0)(980)(0) -> eta pi(0)) = [1.66(-0.66)(+0.81)(stat) +/- 0.11(syst) x 10(-4). This is the first time the a(0)(980) meson has been measured in a D-0 semileptonic decay, which would open one more interesting page in the investigation of the nature of the puzzling a(0)(980) states.
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| 4. |
- Ablikim, M., et al.
(author)
-
Search for invisible decays of omega and phi with J/psi data at BESIII
- 2018
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In: Physical Review D. - : American Physical Society. - 2470-0010 .- 2470-0029. ; 98:3
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Journal article (peer-reviewed)abstract
- Using a data sample of (1310.6 +/- 7.0) x 10(6) J/psi events collected with the BESIII detector operating at the BEPCII collider, we perform the first experimental search for invisible decays of a light vector meson (V = omega, phi) via J/psi -> V-eta decays. The decay of eta -> pi(+)pi(-)pi(0) is utilized to tag the V meson decaying into the invisible final state. No evidence for a significant invisible signal is observed, and the upper limits on the ratio of branching fractions at the 90% confidence level are determined to be B(omega -> invisible)/B(omega -> pi(+)pi(-)pi(0)) < 8.1 x 10(-5) and B(phi -> invisible)/B(phi -> K+K-) < 3.4 x 10(-4). By using the world average values of B(omega -> pi(+)pi(-)pi(0) and B(phi -> K+K-,) the upper limits on the decay branching fractions at the 90% confidence level are set as B(omega -> invisible) < 7.3 x 10(-5) and B(phi -> invisible) < 1.7 x 10(-4), respectively.
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| 5. |
- Ablikim, M., et al.
(author)
-
First measurement of e(+)e(-) -> pK(S)(0)(n)over-barK(-) + c.c. above open charm threshold
- 2018
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In: Physical Review D. - 2470-0010 .- 2470-0029. ; 98:3
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Journal article (peer-reviewed)abstract
- The process e(+)e(-) -> pK(S)(0)(n) over barK(-) + c.c. and its intermediate processes are studied for the first time, using data samples collected with the BESIII detector at BEPCII at center-of-mass energies of 3.773, 4.008, 4.226, 4.258, 4.358, 4.416, and 4.600 GeV, with a total integrated luminosity of 7.4 fb(-1). The Born cross section of e(+)e(-) -> pK(S)(0)(n) over barK(-) + c.c. is measured at each center-of-mass energy, but no significant resonant structure in the measured cross-section line shape between 3.773 and 4.600 GeV is observed. No evident structure is detected in the pK(-), nK(S)(0), pK(S)(0), nK(+), p (n) over bar, or (KSK-)-K-0 invariant mass distributions except for Lambda(1520). The Born cross sections of e(+)e(-) -> Lambda(1520)(n) over barK(S)(0) + c.c. and e(+)e(-) -> Lambda(1520)(p) over barK(+) + c.c. are measured, and the 90% confidence level upper limits on the Born cross sections of e(+)e(-) -> Lambda(1520)(Lambda) over bar (1520) are determined at the seven center-of-mass energies. There is an evident difference in line shape and magnitude of the measured cross sections between e(+)e(-) -> Lambda(1520)(-> pK(-))(n) over barK(S)(0) and e(+)e(-) -> pK-(Lambda) over bar (1520)(-> (n) over barK(S)(0)).
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| 6. |
- Ablikim, M., et al.
(author)
-
Measurement of e(+)e(-) -> K(K)over-barJ/psi cross sections at center-of-mass energies from 4.189 to 4.600 GeV
- 2018
-
In: Physical Review D. - : AMER PHYSICAL SOC. - 2470-0010 .- 2470-0029. ; 97:7
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Journal article (peer-reviewed)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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| 7. |
- Ablikim, M., et al.
(author)
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Measurement of the absolute branching fraction of D*(s0) (2317)(+/-) -> pi D-0(s)+/-
- 2018
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In: Physical Review D. - : American Physical Society. - 2470-0010 .- 2470-0029. ; 97:5
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Journal article (peer-reviewed)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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| 8. |
- Ablikim, M., et al.
(author)
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Observation of e(+)e(-) -> gamma X(3872) at BESIII
- 2014
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In: Physical Review Letters. - 0031-9007 .- 1079-7114. ; 112:9, s. 092001-
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Journal article (peer-reviewed)abstract
- With data samples collected with the BESIII detector operating at the BEPCII storage ring at center-of-mass energies from 4.009 to 4.420 GeV, the process e(+)e(-) -> gamma X(3872) is observed for the first time with a statistical significance of 6.3 sigma. The measured mass of the X(3872) is (3871.9 +/- 0.7(stat) +/- 0.2(syst)) MeV/c(2), in agreement with previous measurements. Measurements of the product of the cross section sigma[e(+)e(-) -> gamma X(3872)] and the branching fraction B [X(3872) -> pi(+)pi(-)J/psi] at center-of-mass energies 4.009, 4.229, 4.260, and 4.360 GeV are reported. Our measurements are consistent with expectations for the radiative transition process Y(4260) -> gamma X(3872).
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| 9. |
- Ablikim, M., et al.
(author)
-
Observation of eta' -> pi(+) pi(-) pi(+) pi(-) and eta' -> pi(+) pi(-) pi(0) pi(0)
- 2014
-
In: Physical Review Letters. - 0031-9007 .- 1079-7114. ; 112:25, s. 251801-
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Journal article (peer-reviewed)abstract
- Using a sample of 1.3 x 10(9) J/psi events collected with the BESIII detector, we report the first observation of eta' -> pi(+) pi(-) pi(+) pi(-) and eta' -> pi(+) pi(-) pi(0) pi(0). The measured branching fractions are B(eta' -> pi(+) pi(-) pi(+) pi(-)) = [8.53 +/- 0.69(stat.) +/- 0.64(syst.)] x 10(-5) and B(eta' -> pi(+) pi(-) pi(0) pi(0)) = [1.82 +/- 0.35(stat.) +/- 0.18(syst.)] x 10(-4), which are consistent with theoretical predictions based on a combination of chiral perturbation theory and vector-meson dominance.
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| 10. |
- Ablikim, M., et al.
(author)
-
Observation of psi(3686) -> eta ' e(+)e(-)
- 2018
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In: Physics Letters B. - : ELSEVIER SCIENCE BV. - 0370-2693 .- 1873-2445. ; 783, s. 452-458
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Journal article (peer-reviewed)abstract
- Using a data sample of 448.1 x 10(6) psi(3686) events collected with the BESIII detector at the BEPCII collider, we report the first observation of the electromagnetic Dalitz decay psi(3686) -> eta'e(+)e(-), with significances of 7.0 sigma and 6.3 sigma when reconstructing the eta' meson via its decay modes eta' -> gamma pi(+)pi(-) and eta' -> pi(+)pi(-) eta (eta -> gamma gamma), respectively. The weighted average branching fraction is determined to be B(psi(3686) -> eta'e(+)e(-)) = (1.90 +/- 0.25 +/- 0.11) x 10(-6), where the first uncertainty is statistical and the second systematic.
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