| 1. |
- Aartsen, M. G., et al.
(författare)
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Searching for eV-scale sterile neutrinos with eight years of atmospheric neutrinos at the IceCube Neutrino Telescope
- 2020
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Ingår i: Physical Review D. - : AMER PHYSICAL SOC. - 1550-7998 .- 1550-2368. ; 102:5
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Tidskriftsartikel (refereegranskat)abstract
- We report in detail on searches for eV-scale sterile neutrinos, in the context of a 3 + 1 model, using eight years of data from the IceCube Neutrino Telescope. By analyzing the reconstructed energies and zenith angles of 305,735 atmospheric nu(mu) and (nu) over bar (mu) events we construct confidence intervals in two analysis spaces: sin(2)(2 theta(24)) vs Delta m(41)(2) under the conservative assumption theta(34) = 0; and sin(2)(2 theta(24)) vs sin(2)(2 theta(34)) given sufficiently large Delta m(41)(2) that fast oscillation features are unresolvable. Detailed discussions of the event selection, systematic uncertainties, and fitting procedures are presented. No strong evidence for sterile neutrinos is found, and the best-fit likelihood is consistent with the no sterile neutrino hypothesis with a p value of 8% in the first analysis space and 19% in the second.
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| 2. |
- Abazov, V. M., et al.
(författare)
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Studies of X(3872) and psi(2S) production in p(p)over-bar collisions at 1.96 TeV
- 2020
-
Ingår i: Physical Review D. - : AMER PHYSICAL SOC. - 1550-7998 .- 1550-2368. ; 102:7
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Tidskriftsartikel (refereegranskat)abstract
- We present various properties of the production of the X(3872) and psi(2S) states based on 10.4 fb(-1) collected by the D0 experiment in Tevatron p (p) over bar collisions at root s = 1.96 TeV. For both states, we measure the nonprompt fraction f(NP) of the inclusive production rate due to decays of b-flavored hadrons. We find the f(NP) values systematically below those obtained at the LHC. The f(NP) fraction for psi(2S) increases with transverse momentum, whereas for the X(3872) it is constant within large uncertainties, in agreement with the LHC results. The ratio of prompt to nonprompt psi(2S) production, ( 1 - f(NP))/f(NP), decreases only slightly going from the Tevatron to the LHC, but for the X(3872), this ratio decreases by a factor of about 3. We test the soft-pion signature of the X(3872) modeled as a weakly bound charm-meson pair by studying the production of the X(3872) as a function of the kinetic energy of the X(3872) and the pion in the X(3872)pi center-of-mass frame. For a subsample consistent with prompt production, the results are incompatible with a strong enhancement in the production of the X(3872) at the small kinetic energy of the X(3872) and the pi in the X(3872)pi center-of-mass frame expected for the X + soft-pion production mechanism. For events consistent with being due to decays of b hadrons, there is no significant evidence for the soft-pion effect, but its presence at the level expected for the binding energy of 0.17 MeV and the momentum scale Lambda = M(pi) is not ruled out.
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| 3. |
- Ablikim, M., et al.
(författare)
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Improved model-independent determination of the strong-phase difference between D0 and ¯D0→K0S,LK+K− decays
- 2020
-
Ingår i: Physical Review D. - : AMER PHYSICAL SOC. - 1550-7998 .- 1550-2368. ; 102:5
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Tidskriftsartikel (refereegranskat)abstract
- We present a measurement of the strong-phase difference between D-0 and (D) over bar (0) -> (KS,LK+K-)-K-0 decays, performed through a study of quantum-entangled pairs of charm mesons. The measurement exploits a data sample equivalent to an integrated luminosity of 2.93 fb(-1), collected by the BESIII detector in e(+)e(-) collisions corresponding to the mass of the psi(3770) resonance. The strong-phase difference is an essential input to the determination of the Cabibbo-Kobayashi-Maskawa (CKM) angle gamma/phi(3) through the decay B- -> DK-, where D can be either a D-0 or a (D) over bar (0) decaying to (KS,LK+K-)-K-0. This is the most precise measurement to date of the strong-phase difference in these decays.
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| 4. |
- Ablikim, M., et al.
(författare)
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Inclusive charged and neutral particle multiplicity distributions in chi(cJ) and J/psi decays
- 2020
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Ingår i: Physical Review D. - : AMER PHYSICAL SOC. - 1550-7998 .- 1550-2368. ; 102:5
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Tidskriftsartikel (refereegranskat)abstract
- Using a sample of 106 million psi(3686) decays, psi(3686) -> gamma chi(cJ) (J = 0, 1, 2) and psi(3686) -> gamma chi(cJ), chi(cJ) -> gamma J/psi (J = 1, 2) events are utilized to study inclusive chi(cJ )-> anything, chi(cJ )-> hadrons, and J/psi( )-> anything distributions, including distributions of the number of charged tracks, electromagnetic calorimeter showers, and pi(0)s, and to compare them with distributions obtained from the BESIII Monte Carlo simulation. Information from each Monte Carlo simulated decay event is used to construct matrices connecting the detected distributions to the input predetection "produced" distributions. Assuming these matrices also apply to data, they are used to predict the analogous produced distributions of the decay events. Using these, the charged particle multiplicities are compared with results from MARK I. Further, comparison of the distributions of the number of photons in data with those in Monte Carlo simulation indicates that G-parity conservation should be taken into consideration in the simulation.
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| 5. |
- Ablikim, M., et al.
(författare)
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Measurement of singly Cabibbo-suppressed decays D -> ωππ
- 2020
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Ingår i: Physical Review D. - : American Physical Society (APS). - 1550-7998 .- 1550-2368. ; 102:5
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Tidskriftsartikel (refereegranskat)abstract
- Using 2.93 fb(-1) of e(+) e(-) collision data taken at a center-of-mass energy of 3.773 GeV by the BESIII detector at the BEPCII, we measure the branching fractions of the singly Cabibbo-suppressed decays D -> omega pi pi to be B(D-0 -> omega pi(+) pi(-)) = (1.33 +/- 0.16 +/- 0.12) x 10(-3) and B(D+ -> omega pi(+)pi(0)) = (3.87 +/- 0.83 +/- 0.25) x 10(-3), where the first uncertainties are statistical and the second ones systematic. The statistical significances are 12.9 sigma and 7.7 sigma, respectively. The precision of B(D-0 -> omega pi(+) pi(-)) is improved by a factor of 2.1 over prior measurements, and B(D+ -> omega pi(+) pi(0)) is measured for the first time. No significant signal for D-0 -> omega pi(0)pi(0) is observed, and the upper limit on the branching fraction is B(D-0 -> omega pi(0)pi(0)) < 1.10 x 10(-3) at the 90% confidence level. The branching fractions of D -> eta pi pi are also measured and consistent with existing results.
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| 6. |
- Ablikim, M., et al.
(författare)
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Measurement of the Born cross sections for e+e−→D+sDs1(2460)−+c.c. and e+e−→D*+sDs1(2460)−+c.c.
- 2020
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Ingår i: Physical Review D. - 1550-7998 .- 1550-2368. ; 101:11
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Tidskriftsartikel (refereegranskat)abstract
- The processes e(+)e(-) -> D-s(+) D-s1 (2460)(-) + c.c. and e(+) e(-) -> D-s*(+) D-s1 (2460)(-)+ c.c. are studied for the first time using data samples collected with the BESIII detector at the BEPCII collider. The Born cross sections of e(+)e(-) -> D-s(+) D-s1 (2460)(-) + c.c. at nine center-of-mass energies between 4.467 GeV and 4.600 GeV and those of e(+) e(-) -> D-s*(+) D-s1 (2460)(-)+ c.c. at root s = 4.590 GeV and 4.600 GeV are measured. No obvious charmonium or charmoniumlike structure is seen in the measured cross sections.
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| 7. |
- Ablikim, M., et al.
(författare)
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Measurements of the absolute branching fractions of D0(+)→K¯Kππ decays
- 2020
-
Ingår i: Physical Review D. - : American Physical Society (APS). - 1550-7998 .- 1550-2368. ; 102:5
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Tidskriftsartikel (refereegranskat)abstract
- Based on e(+)e(-) collision data sample corresponding to an integrated luminosity of 2.93 fb- 1 taken at a center-of-mass energy of 3.773 GeV by the BESIII detector, we report the measurements of the absolute branching fractions of D-0 -> K+K- pi(0 pi 0), D-0 -> (KSKS0)-K-0 pi(+)pi(-), D-0 -> (KSKS-)-K-0 pi(+)pi(-), D-0 -> (KSKS0)-K-0 pi(+)pi(-) D-0 -> (KSKS0)-K-0 pi(+)pi(-), D-0 -> (KSKS0)-K-0 pi(+)pi(-), D-0 -> (KSKS0)-K-0 pi(+)pi(-), and Dthorn. D-0 -> (KSKS0)-K-0 pi(+)pi(-). The decays D-0 -> (KSKS0)-K-0 pi(+)pi(-), D-0 -> (KSKS0)-K-0 pi(+)pi(-), D-0 -> (KSKS0)-K-0 pi(+)pi(-), and D-0 -> (KSKS0)-K-0 pi(+)pi(-) are observed for the first time. The branching fractions of the decays D-0 -> (KSKS0)-K-0 pi(+)pi(-), D-0 -> (KSKS0)-K-0 pi(+)pi(-), Dthorn. D-0 -> (KSKS0)-K-0 pi(+)pi(-). D-0 -> (KSKS0)-K-0 pi(+)pi(-) are measured with improved precision compared to the world-average values.
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| 8. |
- Ablikim, M., et al.
(författare)
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Model-independent determination of the relative strong-phase difference between D-0 and (D)over-bar(0) -> K-S,L(0)pi(+)pi(-) and its impact on the measurement of the CKM angle gamma/phi(3)
- 2020
-
Ingår i: Physical Review D. - : AMER PHYSICAL SOC. - 1550-7998 .- 1550-2368. ; 101:11
-
Tidskriftsartikel (refereegranskat)abstract
- Crucial inputs for a variety of CP-violation studies can be determined through the analysis of pairs of quantum-entangled neutral D mesons, which are produced in the decay of the psi(3770) resonance. The relative strong-phase parameters between D-0 and (D) over bar (0) in the decays D-0 -> K-S,L(0)pi(+)pi(-) are studied using 2.93 fb(-1) of e(+)e(-) annihilation data delivered by the BEPCII collider and collected by the BESIII detector at a center-of-mass energy of 3.773 GeV. Results are presented in regions of the phase space of the decay. These are the most precise measurements to date of the strong-phase parameters in D-0 -> K-S,L(0)pi(+)pi(-) decays. Using these parameters, the associated uncertainty on the Cabibbo-Kobayashi-Maskawa angle gamma/phi(3) is expected to be between 0.7 degrees and 1.2 degrees for an analysis using the decay B-+/- -> DK +/-, D -> K-S(0)pi(+)pi(-), where D represents a superposition of D-0 and (D) over bar (0) states. This is a factor of 3 smaller than that achievable with previous measurements. Furthermore, these results provide valuable input for charm-mixing studies, other measurements of CP violation, and the measurement of strong-phase parameters for other D-decay modes.
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| 9. |
- Ablikim, M., et al.
(författare)
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Observation of a structure in e(+)e(-) -> phi eta ' at root s from 2.05 to 3.08 GeV
- 2020
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Ingår i: Physical Review D. - 1550-7998 .- 1550-2368. ; 102:1
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Tidskriftsartikel (refereegranskat)abstract
- The process e(+)e(-) -> phi eta' has been studied for the first time in detail using data sample collected with the BESIII detector at the BEPCII collider at center of mass energies from 2.05 to 3.08 GeV. A resonance with quantum numbers J(PC) = 1(--) is observed with mass M = (2177.5 +/- 4.8(stat) +/- 19.5(syst))MeV/c(2) and width Gamma = (149.0 +/- 15.6(stat) +/- 8.9(syst)) MeV with a statistical significance larger than 10 sigma, including systematic uncertainties. If the observed structure is identified with the phi(2170), then the ratio of partial width between the phi eta' by BESIII and phi eta by BABAR is (B-phi eta(R)Gamma(R)(ee))1(B-phi eta'(R)Gamma(R)(ee)) = 0.23 +/- 0.10(stat) +/- 0.18(syst), which is smaller than the prediction of the s (s) over barg hybrid models by several orders of magnitude.
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| 10. |
- Ablikim, M., et al.
(författare)
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Observation of the Y(4220) and Y(4390) in the process e(+)e(-) -> eta J/psi
- 2020
-
Ingår i: Physical Review D. - : AMER PHYSICAL SOC. - 1550-7998 .- 1550-2368. ; 102:3
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Tidskriftsartikel (refereegranskat)abstract
- The cross sections of the process e(+)e(-) -> eta J/psi lip at center-of-mass energies (root s) between 3.81 and 4.60 GeV are measured with high precision by using data samples collected with the BESIII detector operating at the BEPCII storage ring. Three structures are observed by analyzing the line shape of the measured cross sections, and a maximum-likelihood fit including three resonances is performed by assuming the lowest lying structure is the psi(4040). For the other resonances, we obtain masses of (4218.6 +/- 3.8 +/- 2.5) and (4382.0 +/- 13.3 +/- 1.7) MeV/c(2) with corresponding widths of (82.0 +/- 5.7 +/- 0.4) and (135.8 +/- 60.8 +/- 22.5) MeV, respectively, where the first uncertainties are statistical and the second ones systematic. The measured resonant parameters are consistent with those of the Y(4220) and Y(4390) from previous measurements of different final states. For the first time, we observe the decays of the Y(4220) and Y(4390) into eta J/psi final states.
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