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Gilman, A.

Publications and source records attributed to Gilman, A..

At least 37 records · Page 2
All sourcesNASA NTRSDOE OSTI
DOE OSTI2024

Observation of ψ(3686) → $$ {\varOmega}^{-}{K}^{+}{\overline{\Xi}}^0 $$ + c.c.

Abstract Using (27.12±0.14)×10 8 ψ(3686) events collected with the BESIII detector at BEPCII, the decay ofψ(3686)→$$ {\varOmega}^{-}{K}^{+}{\overline{\Xi}}^0 $$ Ω − K + Ξ ¯ 0 + c.c.is observed for the first time. The branching fraction of this decay is measured to be$$ {\mathcal{B}}_{\psi (3686)\to {\varOmega}^{-}{K}^{+}{\overline{\Xi}}^0+\textrm{c}.\textrm{c}.} $$ B ψ 3686 → Ω − K + Ξ ¯ 0 + c . c . = (2.78 ± 0.40 ± 0.18) × 10 −6 , where the first uncertainty is statistical and the second is systematic. Possible baryon excited states are searched for in this decay, but no evident intermediate state is observed with the current sample size.

Physics↗
DOE OSTI2024

Search for the semi-muonic charmonium decay J/ψ → D−μ+νμ + c.c.

Abstract Using (10087 ± 44) × 10 6 J/ψevents collected with the BESIII detector at the BEPCIIe + e − storage ring at the center-of-mass energy of$$ \sqrt{s} $$ s = 3.097 GeV, we present a search for the rare semi-muonic charmonium decayJ/ψ→D − μ + ν μ + c.c.. Since no significant signal is observed, we set an upper limit of the branching fraction to be$$ \mathcal{B} $$ B (J/ψ→D − μ + ν μ + c.c.) < 5.6 × 10 −7 at 90% confidence level. This is the first search for the weak decay of charmonium with a muon in the final state.

Physics↗
DOE OSTI2024

Measurement of the e+e− → $$ {K}_S^0{K}_L^0 $$π0 cross sections from $$ \sqrt{s} $$ = 2.000 to 3.080 GeV

Abstract Based one + e − collision data collected at center-of-mass energies from 2.000 to 3.080 GeV by the BESIII detector at the BEPCII collider, a partial wave analysis is performed for the processe + e − →$$ {K}_S^0{K}_L^0 $$ K S 0 K L 0 π 0 . The results allow the Born cross sections of the processe + e − →$$ {K}_S^0{K}_L^0 $$ K S 0 K L 0 π 0 , as well as its subprocessese + e − →K ∗ (892) 0 $$ \overline{K} $$ K ¯ 0 and$$ {K}_2^{\ast } $$ K 2 ∗ (1430) 0 $$ \overline{K} $$ K ¯ 0 to be measured. The Born cross sections fore + e − →$$ {K}_S^0{K}_L^0 $$ K S 0 K L 0 π 0 are consistent with previous measurements by BaBar, but with substantially improved precision. The Born cross section lineshape of the processe + e − K ∗ (892) 0 $$ \overline{K} $$ K ¯ 0 is consistent with a vector meson state around 2.2 GeV with a significance of 3.2σ. A Breit-Wigner fit determines its mass asM Y = (2164.7±9.1±3.1) MeV/c 2 and its width as Γ Y = (32.4±21.0±1.8) MeV.

Physics↗
DOE OSTI2023

Measurement of $$ {e}^{+}{e}^{-}\to p{K}^{-}\overline{\Lambda}+c.c. $$ cross sections between 4.009 GeV and 4.951 GeV

Abstract Usinge + e − collision datasets corresponding to a total integrated luminosity of 21.7 fb −1 collected with the BESIII detector at the BEPCII collider at center-of-mass energies ranging from 4.009 GeV to 4.951 GeV, the energy-dependent cross sections of$$ {e}^{+}{e}^{-}\to p{K}^{-}\overline{\Lambda}+c.c. $$ e + e − → p K − Λ ¯ + c . c . are measured for the first time. By fitting these energy-dependent cross sections, we search for the excitedψstatesψ(4160) andψ(4415), and the vector charmonium-like statesψ(4230),ψ(4360), andψ(4660). No evidence for these is observed and the upper limits on the branching fractions of these states decaying into$$ p{K}^{-}\overline{\Lambda}+c.c. $$ p K − Λ ¯ + c . c . are set at the 90% confidence level.

Physics↗
DOE OSTI2023

Studies of the decay $$ {\textrm{D}}_{\textrm{s}}^{+}\to {\textrm{K}}^{+}{\textrm{K}}^{-}{\mu}^{+}{\nu}_{\mu } $$

Abstract The$$ {D}_s^{+}\to {K}^{+}{K}^{-}{\mu}^{+}{\nu}_{\mu } $$ D s + → K + K − μ + ν μ decay is studied based on 7.33 fb −1 ofe + e − collision data collected with the BESIII detector at center-of-mass energies in the range from 4.128 to 4.226 GeV. The absolute branching fraction is measured as$$ \mathcal{B}\left({D}_s^{+}\to \phi {\mu}^{+}{\nu}_{\mu}\right)=\left(2.25\pm 0.09\pm 0.07\right)\times {10}^{-2} $$ B D s + → ϕ μ + ν μ = 2.25 ± 0.09 ± 0.07 × 10 − 2 , the most precise measurement to date. Combining with the world average of$$ \mathcal{B}\left({D}_s^{+}\to \phi {e}^{+}{\nu}_e\right) $$ B D s + → ϕ e + ν e , the ratio of the branching fractions obtained is$$ \frac{\mathcal{B}\left({D}_s^{+}\to \phi {\mu}^{+}{\nu}_{\mu}\right)}{\mathcal{B}\left({D}_s^{+}\to \phi {e}^{+}{\nu}_e\right)}=0.94\pm 0.08 $$ B D s + → ϕ μ + ν μ B D s + → ϕ e + ν e = 0.94 ± 0.08 , in agreement with lepton universality. By performing a partial wave analysis, the hadronic form factor ratios atq 2 = 0 are extracted, finding$$ {r}_V=\frac{V(0)}{A_1(0)}=1.58\pm 0.17\pm 0.02 $$ r V = V 0 A 1 0 = 1.58 ± 0.17 ± 0.02 and$$ {r}_2=\frac{A_2(0)}{A_1(0)}=0.71\pm 0.14\pm 0.02 $$ r 2 = A 2 0 A 1 0 = 0.71 ± 0.14 ± 0.02 , where the first uncertainties are statistical and the second are systematic. No significantS-wave contribution fromf 0 (980)→ K + K − is found. The upper limit$$ \mathcal{B}\left({D}_s^{+}\to {f}_0(980){\mu}^{+}{\nu}_{\mu}\right)\cdot \mathcal{B}\left({f}_0(980)\to {K}^{+}{K}^{-}\right)<5.45\times {10}^{-4} $$ B D s + → f 0 980 μ + ν μ ⋅ B f 0 980 → K + K − < 5.45 × 10 − 4 is set at 90% credibility level.

Physics↗
DOE OSTI2023

Measurement of the branching fractions of the singly Cabibbo-suppressed decays $$ {\Lambda}_{\textrm{c}}^{+}\to \textrm{p}\eta $$ and $$ {\Lambda}_{\textrm{c}}^{+}\to \textrm{p}\omega $$

Abstract Based on 4.5 fb −1 e + e − collision data collected with BESIII detector at seven energy points between 4.600 and 4.699 GeV, the branching fractions for$$ {\Lambda}_c^{+}\to p\eta $$ Λ c + → pη and$$ {\Lambda}_c^{+}\to p\omega $$ Λ c + → pω were measured by means of single-tag method. The branching fractions of$$ {\Lambda}_c^{+}\to p\eta $$ Λ c + → pη and$$ {\Lambda}_c^{+}\to p\omega $$ Λ c + → pω are determined to be (1.57±0.11 stat ±0.04 syst )×10 −3 and (1.11±0.20 stat ±0.07 syst )×10 −3 , with a statistical significance of greater than 10σand 5.7σ, respectively. These results are consistent with the previous measurements by BESIII, LHCb and Belle, and the result of$$ {\Lambda}_c^{+}\to p\eta $$ Λ c + → pη is the most precise to date.

Physics↗
DOE OSTI2023

Measurement of the cross section of $$ {e}^{+}{e}^{-}\to {\Xi}^{-}{\overline{\Xi}}^{+} $$ at center-of-mass energies between 3.510 and 4.843 GeV

Abstract Usinge + e − collision data corresponding to a total integrated luminosity of 12.9 fb −1 collected with the BESIII detector at the BEPCII collider, the exclusive Born cross sections and the effective form factors of the reaction$$ {e}^{+}{e}^{-}\to {\Xi}^{-}{\overline{\Xi}}^{+} $$ e + e − → Ξ − Ξ ¯ + are measured via the single baryon-tag method at 23 center-of-mass energies between 3.510 and 4.843 GeV. Evidence for the decay$$ \psi (3770)\to {\Xi}^{-}{\overline{\Xi}}^{+} $$ ψ 3770 → Ξ − Ξ ¯ + is observed with a significance of 4.5σby analyzing the measured cross sections together with earlier BESIII results. For the other charmonium(-like) statesψ(4040),ψ(4160),Y(4230),Y(4360),ψ(4415), andY(4660), no significant signal of their decay to$$ {\Xi}^{-}{\overline{\Xi}}^{+} $$ Ξ − Ξ ¯ + is found. For these states, upper limits of the products of the branching fraction and the electronic partial width at the 90% confidence level are provided.

Physics↗
DOE OSTI2023

Measurement of Λ transverse polarization in e+e− collisions at $$ \sqrt{s} $$ = 3.68 − 3.71 GeV

Abstract With data samples collected with the BESIII detector at seven energy points at$$ \sqrt{s} $$ s = 3.68−3.71 GeV, corresponding to an integrated luminosity of 333 pb −1 , we present a study of the Λ transverse polarization in thee + e − →$$ \Lambda \overline{\Lambda} $$ Λ Λ ¯ reaction. The significance of polarization by combining the seven energy points is found to be 2.6σincluding the systematic uncertainty, which implies a non-zero phase between the transition amplitudes of the$$ \Lambda \overline{\Lambda} $$ Λ Λ ¯ helicity states. The modulus ratio and the relative phase of EM-psionicform factors combined with all energy points are measured to beR Ψ =$$ {0.71}_{-0.10}^{+0.10} $$ 0.71 − 0.10 + 0.10 ±0.03 and ∆Φ Ψ =$$ {23}_{-8.0}^{+8.8} $$ 23 − 8.0 + 8.8 ±1.6°, where the first uncertainties are statistical and the second systematic.

Physics↗
DOE OSTI2023

Measurement of the branching fraction of ${\textrm{D}}_{\textrm{s}}^{+}$ → τ + ν τ via τ + → μ+ν μ $\overline{\nu}$τ

Utilizing 7 . 33 fb - 1 of e + e - collision data taken at the center-of-mass energies of 4.128, 4.157, 4.178, 4.189, 4.199, 4.209, 4.219, and 4.226 GeV with the BESIII detector, the branching fraction of the leptonic decay ${D}_s^{+}$ → τ + ν τ via τ + → μ + ν μ $\overline{\nu}$ τ is measured to be ${\mathcal{B}}_{D_s^{+}\to {\tau}^{+}{\nu}_{\tau }}$ = (5 . 37 ± 0 . 17 stat ± 0 . 15 syst )%. Combining this branching fraction with the world averages of the measurements of the masses of τ + and ${D}_s^{+}$ as well as the lifetime of ${D}_s^{+}$, we extract the product of the decay constant of ${D}_s^{+}$ and the c → s Cabibbo-Kobayashi-Maskawa matrix element to be ${f}_{D_s^{+}}$ |V cs | = (246 . 7 ± 3 . 9 stat ± 3 . 6 syst ) MeV. Taking |V cs | from a global fit in the standard model we obtain ${f}_{D_s^{+}}$ = (253 . 4 ± 4 . 0 stat ± 3 . 7 syst ) MeV. Conversely, taking ${f}_{D_s^{+}}$ from lattice quantum chromodynamics calculations, we obtain |V cs | = 0 . 987 ± 0 . 016 stat ± 0 . 014 syst .

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗
DOE OSTI2023

Measurement of branching fractions of ${\Lambda}_{\textrm{c}}^{+}$ decays to Σ⁺K⁺K⁻, Σ⁺Φ and Σ⁺K⁺π⁻(π 0 )

Based on 4.5 fb - 1 data taken at seven center-of-mass energies ranging from 4.600 to 4.699 GeV with the BESIII detector at the BEPCII collider, we measure the branching fractions of \( {\Lambda}_c^{+} \) → Σ + + hadrons relative to \( {\Lambda}_c^{+} \) → Σ + π + π - . Combining with the world average branching fraction of \( {\Lambda}_c^{+} \) → Σ + π + π - , their branching fractions are measured to be (0 . 377 ± 0 . 042 ± 0 . 020 ± 0 . 021)% for \( {\Lambda}_c^{+} \) → Σ + K + K - , (0 . 200 ± 0 . 023 ± 0 . 011 ± 0 . 011)% for \( {\Lambda}_c^{+} \) → Σ + K + π - , (0 . 414 ± 0 . 080 ± 0 . 030 ± 0 . 023)% for \( {\Lambda}_c^{+} \) → Σ + Φ and (0 . 197 ± 0 . 036 ± 0 . 009 ± 0 . 011)% for \( {\Lambda}_c^{+} \) → Σ + K + K - (non- Φ ). In all the above results, the first uncertainties are statistical, the second are systematic and the third are from external input of the branching fraction of \( {\Lambda}_c^{+} \) → Σ + π + π - . Since no signal for \( {\Lambda}_c^{+} \) → Σ + K + π - π 0 is observed, the upper limit of its branching fraction is determined to be 0.13% at the 90% confidence level.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗
DOE OSTI2023

Study of the e + e - → π + π - ω process at center-of-mass energies between 4.0 and 4.6 GeV

Using 15.6 fb -1 of e + e - collision data collected at twenty-four center-of-mass energies from 4.0 to 4.6 GeV with the BESIII detector, the helicity amplitudes of the process e+e- → π+π-ω are analyzed for the first time. Born cross section measurements of two-body intermediate resonance states with statistical significance greater than 5σ are presented, such as f 0 (500), f 0 (980), f 2 (1270), f 0 (1370), b 1 (1235) ± , and ρ(1450) ± . In addition, evidence of a resonance state in e + e - → π + π - ω production is found. The mass of this state obtained by line shape fitting is about 4.2 GeV/c 2 , which is consistent with the production of ψ(4160) or Y(4220).

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗