Engineering topics

Branchini, P. (ORCID:0000000222709673)

Publications and source records attributed to Branchini, P. (ORCID:0000000222709673).

107 records · Page 6

DOE OSTI2023

Observation of e + e – → ω χ b J ( 1 P ) and Search for X b → ω Υ ( 1 S ) at s near 10.75 GeV

We study the processes $e^{+}e^{–} → ωχ_{bJ}$(1P) (J=0, 1, or 2) using samples at center-of-mass energies $\sqrt{s}$ = 10.701, 10.745, and 10.805 GeV, corresponding to 1.6, 9.8, and 4.7 fb –1 of integrated luminosity, respectively. These data were collected with the Belle II detector during special operations of the SuperKEKB collider above the Υ(4S) resonance. We report the first observation of $ωχ_{bJ}$(1P) signals at $\sqrt{s}$ = 10.745 GeV. By combining Belle II data with Belle results at $\sqrt{s}$ = 10.867 GeV, we find energy dependencies of the Born cross sections for $e^{+}e^{–} → ωχ_{b1,b2}$(1P) to be consistent with the shape of the Υ(10753) state. These data indicate that the internal structures of the Υ(10753) and Υ(10860) states may differ. Including data at $\sqrt{s}$ = 10.653 GeV, we also search for the bottomonium equivalent of the X(3872) state decaying into ωΥ(1S). No significant signal is observed for masses between 10.45 and 10.65 GeV/c 2 .

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DOE OSTI2023

Angular analysis of the low K + K – invariant mass enhancement in B + →K + K – π + decays

We study the decay B + →K + K – π + and investigate the angular distribution of K + K – pairs with invariant mass below 1.1 GeV / c 2 . This region exhibits both a strong enhancement in signal and very large direct CP violation. We construct a coherent sum model for the angular distribution of the S- and P-wave, and report the ratio of their amplitudes, the relative phase and the forward-backward asymmetry. We also report absolute differential branching fractions and direct CP asymmetry for the decay in bins of M K+K– and the differential branching fractions in bins of M K+π– . The results are based on a data sample that contains 772 × 10 6 $B\bar{B}$ pairs collected at the $Υ$(4S) resonance with the Belle detector at the KEKB asymmetric-energy e + e – collider. The result favors the presence of S- and D-waves in low M K+K– region to the detriment of a P-wave.

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DOE OSTI2023

Measurement of the B + /B 0 production ratio in e + e - collisions at the $\Upsilon$ (4S) resonance using B → J/Ψ($\ell\ell$)K decays at Belle

We measure the ratio of branching fractions for the $\Upsilon$ (4S) decays to B + B - and B 0 $\bar{B}$ 0 using B + → J/Ψ($\ell\ell$)K + and B 0 → J/Ψ($\ell\ell$)K 0 samples, where J/Ψ($\ell\ell$) stands for J/Ψ → $\ell$ + $\ell$ - ($\ell$ = e or μ), with 711 fb -1 of data collected at the $\Upsilon$ (4S) resonance with the Belle detector. We find the decay rate ratio of $\Upsilon$ (4S) → B + B - over $\Upsilon$ (4S) → B 0 $\bar{B}$ 0 to be 1.065 ± 0.012 ± 0.019 ± 0.047, which is the most precise measurement to date. The first and second uncertainties are statistical and systematic, respectively, and the third uncertainty is due to the assumption of isospin symmetry in B → J/Ψ($\ell\ell$) K.

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DOE OSTI2023

Search for CP violation and measurement of branching fractions and decay asymmetry parameters for Λ$^+_c$ → Λ h + and Λ$^+_c$ → Σ 0 h + ( h = K, π )

Here, we report a study of Λ$^+_c$ → Λ h + and Λ$^+_c$ → Σ 0 h + ( h = K, π ) decays based on a data sample of 980 fb -1 collected with the Belle detector at the KEKB energy-asymmetric e + e - collider. The first results of direct CP asymmetry in two-body singly Cabibbo-suppressed (SCS) decays of charmed baryons are measured, A$^{dir}_{CP}(Λ^+_{c} → ΛK^{+})$ = +0.021 ± 0.026 ± 0.001 and A$^{dir}_{CP}(Λ^+_{c} → Σ^{0}K^{+})$ = +0.025 ± 0.054 ± 0.004. We also make the most precise measurement of the decay asymmetry parameters (α) for the four modes of interest and search for CP violation via the α-induced CP asymmetry (A$^α_{CP}$ ). We measure A$^α_{CP}$ ($Λ^+_{c} → ΛK^{+}$) = -0.023 ± 0.086 ± 0.071 and A$^α_{CP}$ ($Λ^+_{c} → Σ^{0}K^{+}$) = +0.08 ± 0.35 ± 0.14, which are the first A$^α_{CP}$ results for SCS decays of charmed baryons. We search for Λ -hyperon CP violation in $Λ^+_{c}$ → (Λ, Σ 0 )π + and find A$^α_{CP}$(Λ → pπ - ) = +0.013 ± 0.007 ± 0.011 . This is the first time that hyperon CP violation has been measured via Cabibbo-favored charm decays. No evidence of baryon CP violation is found. We also obtain the most precise branching fractions for two SCS Λ$^+_c$ decays, $\mathscr{B}$($Λ^+_{c} → ΛK^{+}$) = (6.57 ± 0.17 ± 0.11 ± 0.35) x 10 -4 and $\mathscr{B}$($Λ^+_{c} → Σ^{0}K^{+}$) = (3.58 ± 0.19 ±0.06 ±0.19) x 10 -4 . The first uncertainties are statistical and the second systematic, while the third uncertainties come from the uncertainties on the world average branching fractions of $Λ^+_{c}$ → (Λ, Σ 0 )π + .

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DOE OSTI2023

Measurement of the mass and width of the Λ c ⁢(2625) + charmed baryon and the branching ratios of Λ c ⁢(2625) + → Σ$^{0}_{c}$π + and Λ c ⁢(2625) + → Σ$^{++}_{c}$π -

Using the entire data sample of 980 fb -1 collected at or near the Y⁡(4⁢S) resonance with the Belle detector operating at the KEKB asymmetric-energy e + ⁢e - collider, we report the measurement of the mass, width, and the branching ratios of the Λ c (2625) + charmed baryon. The mass difference between Λ c ⁢(2625) + and Λ$^{+}_{c}$ is measured to be M⁡(Λ c ⁢(2625) + )-M⁡(Λ$^{+}_{c}$)=341.518±0.006±0.049 MeV/c 2 . The upper limit on the width is measured to be Γ⁡(Λ c ⁢(2625) + )<0.52 MeV/c 2 at 90% confidence level. Based on a full Dalitz plot fit, branching ratios with respect to the mode Λ c⁢ (2625) + →Λ$^{+}_{c}$π + ⁢π - are measured to be $\frac{\mathscr{B}⁡(Λ_c(2625)^+ → Σ^{0}_{c}π^+)} {\mathscr{B}⁡(Λ_c(2625)^+ → ^{+}_{c}⁢π^+⁢π^-)}$ = (5.19±0.23±0.40)% and $\frac{\mathscr{B}(Λ_c (2625)^+ → Σ{_c^+}^+ π^-)}{\mathscr{B}(Λ_c (2625)^+ → Λ{_c^+} π^+π^-)}$ = (5.13±0.26±0.32)%, where the first and second uncertainties are statistical and systematic, respectively. These measurements can be used to further constrain the parameters of the underlying theoretical models.

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DOE OSTI2023

Measurement of the $Ω_c^0$ lifetime at Belle II

We report on a measurement of the $Ω_c^0$ lifetime using $Ω_c^0$ → Ω-π + decays reconstructed in c data collected by the Belle II experiment and corresponding to 207 fb -1 of integrated e + e - → c luminosity. The result, τ ($Ω_c^0$) = 243 ± 48 (stat) ± 11 (syst) fs, agrees with recent measurements indicating that the $Ω_c^0$ is not the shortest-lived weakly decaying charmed baryon.

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DOE OSTI2023

Search for a Dark Photon and an Invisible Dark Higgs Boson in $μ^+ μ^–$ and Missing Energy Final States with the Belle II Experiment

The dark photon $\textit{A'}$ and the dark Higgs boson $\textit{h'}$ are hypothetical particles predicted in many dark sector models. We search for the simultaneous production of A' and h' in the dark Higgsstrahlung process $e^+e^– → A' h'$ with $A' → μ^+μ^–$ and $\textit{h'}$ invisible in electron-positron collisions at a center-of- mass energy of 10.58 GeV in data collected by the Belle II experiment in 2019. With an integrated luminosity of 8.34 fb –1 , we observe no evidence for signal. We obtain exclusion limits at 90% Bayesian credibility in the range of 1.7-5.0 fb on the cross section and in the range of 1.7 × 10 –8 -200 × 10 –8 on the effective coupling $ε^2 × α_D$ for the $\textit{A'}$ mass in the range of 4.0 GeV/$c^2 < M_{A'}$ < 9.7 GeV/$c^2$ and for the $\textit{h'}$ mass $M_{h'} < M_{A'}$, where $\textit{ε}$ is the mixing strength between the standard model and the dark photon and $α_D$ is the coupling of the dark photon to the dark Higgs boson. Our limits are the first in this mass range. Phtysuc

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DOE OSTI2023

Search for rare decays B + → D s ( * ) + η , D s ( * ) + K ¯ 0 , D + η , and D + K 0

We present a study of rare decay modes B + → D$^{+}_{s}$ℎ 0 , B + → D$^{*}_{s}$⁢ + ℎ 0 , and B + → D + ⁢ℎ 0 , where ℎ 0 denotes the neutral meson η or K 0 , using a data sample of (772 ±10) ×10 6 B$\overline{B}$ events produced at the Υ⁡(4⁢S) resonance. The data were collected by the Belle detector operating at the asymmetric-energy KEKB collider. We find no evidence for these decays, so we set upper limits at the 90% confidence level on the branching fractions of , , and D + ⁢ℎ 0 decay modes. Along with these rare decay modes, we report improved measurements of the color-suppressed decay branching fractions $\mathscr{B}$⁡($\overline{B}$ 0 →D 0 ⁢η) =(26.6 ±1.2 ±2.1) ×10 -5 and $\mathscr{B}$⁡($\overline{B}$) 0 →D 0 ⁢ $\overline{K}$ 0 ) =(5.6 ±0.5 ±0.2) ×10 -5 . The first and second quoted uncertainties are statistical and systematic, respectively.

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DOE OSTI2023

Measurement of the Λ$^+_c$ Lifetime

An absolute measurement of the Λ$^+_c$ lifetime is reported using Λ$^+_c → pK^– π^+$ decays in events reconstructed from data collected by the Belle II experiment at the SuperKEKB asymmetric-energy electron-positron collider. The total integrated luminosity of the data sample, which was collected at center-of-mass energies at or near the $\textit{Υ}(4S)$ resonance, is 207.2 fb –1 . The result, $τ(Λ^+_c)$ = 203.20 ± 0.89 ± 0.77 fs , where the first uncertainty is statistical and the second

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗

DOE OSTI2023

Measurement of branching fractions of Λ$^+_c$ → p⁢K$^0_S$K$^0_S$ and Λ$^+_c$ → p⁢K$^0_S$⁢η at Belle

We present a study of a singly Cabibbo-suppressed decay Λ$^+_c$ → p⁢K$^0_S$K$^0_S$ and a Cabibbo-favored decay Λ$^+_c$ → p⁢K$^0_S$⁢η based on 980 fb -1 of data collected by the Belle detector, operating at the KEKB energy-asymmetric e + ⁢e - collider. We measure their branching fractions relative to Λ$^+_c$ → p⁢K$^0_S$: $\mathscr{B}$(Λ$^+_c$ → p⁢K$^0_S$K$^0_S$)/$\mathscr{B}$(Λ$^+_c$ → p⁢K$^0_S$) = (1.48 ± 0.08 ± 0.04) × 10 -2 and $\mathscr{B}$(Λ$^+_c$ → p⁢K$^0_S$η)/$\mathscr{B}$(Λ$^+_c$ → p⁢K$^0_S$) = (2.73 ± 0.06 ± 0.13) × 10 -1 . Combining with the world average $\mathscr{B}$(Λ$^+_c$ → p⁢K$^0_S$), we have the absolute branching fractions, $\mathscr{B}$(Λ$^+_c$ → p⁢K$^0_S$K$^0_S$) = (2.35 ± 0.12 ± 0.07 ± 0.12) × 10 -4 and $\mathscr{B}$(Λ$^+_c$ → p⁢K$^0_S$η) = (4.35 ± 0.10 ± 0.20 ± 0.22) × 10 -3 . The first and second uncertainties are statistical and systematic, respectively, while the third ones arise from the uncertainty on $\mathscr{B}$(Λ$^+_c$ → p⁢K$^0_S$). The mode Λ$^+_c$ → p⁢K$^0_S$K$^0_S$ is observed for the first time and has a statistical significance of >10σ. The branching fraction of Λ$^+_c$ → p⁢K$^0_S$η has been measured with a threefold improvement in precision over previous results and is found to be consistent with the world average.

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DOE OSTI2023

Measurement of the branching fraction of Ξ c 0 → Λ c + π - at Belle

Based on a data sample of 983 fb -1 collected with the Belle detector at the KEKB asymmetric-energy e + ⁢e - collider, we present the study of the heavy-flavor-conserving decay Ξ$^{0}_{c}$ → Λ$^{+}_{c}$⁢π - with Λ$^{+}_{c}$ reconstructed via its p⁢K - π + decay mode. The branching fraction ratio $\mathscr{B}$⁡(Ξ$^{0}_{c}$ → Λ$^{+}_{c}$⁢π - )/$\mathscr{B}$⁡(Ξ$^{0}_{c}$ → Ξ - π + ) is measured to be 0.38 ±0.04 ±0.04. Combining with the world average value of $\mathscr{B}$(Ξ$^{0}_{c}$ → Ξ - π + ), the branching fraction $\mathscr{B}$⁡(Ξ$^{0}_{c}$ → Λ$^{+}_{c}$⁢π - ) is deduced to be (0.54 ±0.05 ±0.05 ±0.12)%. Here, the uncertainties above are statistical, systematic, and from $\mathscr{B}$⁡(Ξ$^{0}_{c}$ → Ξ - π + ), respectively.

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DOE OSTI2023

Measurements of branching fractions of Λ$^{+}_{c}$ → Σ + ⁢η and Λ$^{+}_{c}$ → Σ + ⁢η' and asymmetry parameters of Λ$^{+}_{c}$ → Σ + ⁢π 0 , Λ$^{+}_{c}$ → Σ + ⁢η, and Λ$^{+}_{c}$ → Σ + ⁢η'

We report a study of Λ c + → Σ + π 0 , Λ c + → Σ + η , and Λ c + → Σ + η ' using the data sample corresponding to an integrated luminosity of 980 fb - 1 collected with the Belle detector at the KEKB asymmetric-energy e + e - collider. The branching fractions relative to Λ c + → Σ + π 0 are measured as B Λ c + → Σ + η / B Λ c + → Σ + π 0 = 0.25 ± 0.03 ± 0.01 and B Λ c + → Σ + η ' / B Λ c + → Σ + π 0 = 0.33 ± 0.06 ± 0.02 . Using B Λ c + → Σ + π 0 = ( 1.25 ± 0.10 ) % , we obtain B Λ c + → Σ + η = ( 3.14 ± 0.35 ± 0.17 ± 0.25 ) × 10 - 3 and B Λ c + → Σ + η ' = ( 4.16 ± 0.75 ± 0.25 ± 0.33 ) × 10 - 3 . Here the uncertainties are statistical, systematic, and from B Λ c + → Σ + π 0 , respectively. The ratio of the branching fraction of Λ c + → Σ + η ' with respect to that of Λ c + → Σ + η is measured to be B Λ c + → Σ + η ' / B Λ c + → Σ + η = 1.34 ± 0.28 ± 0.08 . We update the asymmetry parameter of Λ c + → Σ + π 0 , α Σ + π 0 = - 0.48 ± 0.02 ± 0.02 , with a considerably improved precision. The asymmetry parameters of Λ c + → Σ + η and Λ c + → Σ + η ' are measured to be α Σ + η = - 0.99 ± 0.03 ± 0.05 and α Σ + η ' = - 0.46 ± 0.06 ± 0.03 for the first time.

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DOE OSTI2023

Measurement of the branching fractions for Cabibbo-suppressed decays D + → K + K - π + π 0 and D ( s ) + → K + π - π + π 0 at Belle

We present measurements of the branching fractions for the singly Cabibbo-suppressed decays and , and the doubly Cabibbo-suppressed decay , based on of data recorded by the Belle experiment at the KEKB e + ⁢e - collider. We measure these modes relative to the Cabibbo-favored modes D + → K - ⁢π + ⁢π + ⁢π 0 and D$^{+}_{s}$ → K + ⁢K -⁢ π + ⁢π 0 . Our results for the ratios of branching fractions are $\mathscr{B}$⁡(D + →K + ⁢K -⁢ π + ⁢π 0 )/$\mathscr{B}$⁡(D + → K - ⁢π + ⁢π + ⁢π 0 ) =(11.32±0.13±0.26)%, $\mathscr{B}$⁡(D + →K + π - ⁢π + ⁢π 0 )/$\mathscr{B}$(D + →K -⁢ π + ⁢π + ⁢π 0 ) =(1.68±0.11±0.03)%, and $\mathscr{B}$⁡(D$^{+}_{s}$ → K + ⁢π - π + ⁢π 0 )/$\mathscr{B}$⁡(D$^{+}_{s}$ → K + ⁢K - π + π 0 ) =(17.13±0.62±0.51)%, where the uncertainties are statistical and systematic, respectively. The second value corresponds to (5.83 ±0.42) ×tan 4 ⁡θ C , where θ C is the Cabibbo angle; this value is larger than other measured ratios of branching fractions for a doubly Cabibbo-suppressed charm decay to a Cabibbo-favored decay. Multiplying these results by world average values for $\mathscr{B}$⁡(D + → K - ⁢π + ⁢π + ⁢π 0 ) and $\mathscr{B}$⁡(D$^{+}_{s}$ → K + ⁢K - π + π 0 ) yields $\mathscr{B}$( + →K + ⁢K -⁢ π + ⁢π 0 ) = (7.08±0.08±0.16±0.20)×10 -3 , $\mathscr{B}$⁡(D + → K +⁢ π - π + ⁢π 0 ) =(1.05±0.07±0.02±0.03)×10 -3 , and $\mathscr{B}$⁡(D$^{+}_{s}$ → K + ⁢π - π + ⁢π 0 ) =(9.44±0.34±0.28±0.32)×10 -3 , where the third uncertainty is due to the branching fraction of the normalization mode. The first two results are consistent with, but more precise than, the current world averages. The last result is the first measurement of this branching fraction.

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DOE OSTI2023

First search for the weak radiative decays Λ$^+_c$ → Σ + γ and Ξ$^0_c$ → Ξ 0 γ

We present the first search for the weak radiative decays Λ$^+_c$ → Σ + γ and Ξ$^0_c$ → Ξ 0 γ using a data sample of 980 fb -1 collected by the Belle detector operating at the KEKB asymmetric-energy e + e - collider. There are no evident Λ$^+_c$ → Σ + γ or Ξ$^0_c$ → Ξ 0 γ signals. Taking the decays Λ$^+_c$ → pK - π + and Ξ$^0_c$ → Ξ - π + as normalization channels, the upper limits at 90% credibility level on the ratios of branching fractions $\mathcal{B}$(Λ$^+_c$ → Σ + γ)/$\mathcal{B}$(Λ$^+_c$ → pK - π + ) < 4.0 x 10 -3 and $\mathcal{B}$(Ξ$^0_c$ → Ξ 0 γ)/$\mathcal{B}$(Ξ$^0_c$ → Ξ - π + ) < 1.2 x 10 -2 are determined. We obtain the upper limits at 90% credibility level on the absolute branching fractions $\mathcal{B}$(Λ$^+_c$ → Σ + γ) < 2.6 x 10 -4 and $\mathcal{B}$(Ξ$^0_c$ → Ξ 0 γ) < 1.8 x 10 -4 .

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DOE OSTI2023

Study of e + e - → η Φ via initial state radiation at Belle

Using 980 fb -1 of data collected on and around the (n = 1, 2, 3, 4, 5) resonances with the Belle detector at the KEKB collider, we measure the cross section of e + ⁢e - → η⁢Φ from threshold to 3.95 GeV via initial state radiation. There are clear Φ⁡(1680) and J/ψ signals but no significant Φ⁡(2170) signal in the ηΦ final state. The branching fraction $\mathscr{B}$⁡[J/ψ →η⁢Φ] is measured to be (7.2 ±0.8 ±0.5) ×10 -4 . The resonant parameters of Φ⁡(1680) are determined to be m Φ(1680) = (1696±8±10) MeV/c 2 (statistical and systematic errors, respectively), Γ Φ⁡(1680) =(175±13±16) MeV and, depending on the possible presence of predominantly constructive or destructive interference between Φ⁡(1680) and continuum production, Γ$^{e^+e^-}_{Φ⁡(1680)}$·$\mathscr{B}$⁡[Φ⁡(1680)→ηΦ] and $\mathscr{B}$⁡[Φ(1680)→η⁢Φ] are determined to be (75 ±10 ±11) eV and (25±12±2)% or (207±16±20) eV and (23 ±10 ±2)%, respectively. The upper limit for Γ$^{e^+e^-}_{Φ⁡(2170)}$·$\mathscr{B}$⁡[Φ⁡(2170) → ηΦ] is determined to be either 0.17 or 18.6 eV at the 90% confidence level.

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DOE OSTI2023

Measurements of the branching fractions B ( B ¯ 0 → D * + π - ) and B ( B ¯ 0 → D * + K - ) and tests of QCD factorization

Using (771.6 ± 10.6) × 10 6 $B\overline{B}$ meson pairs recorded by the Belle experiment at the KEKB e + e - collider, we report the branching fractions $\mathscr{B}$($\overline{B}$ 0 → D* + π - ) = (2.62 ± 0.02 ± 0.09 X 10 -3 and $\mathscr{B}$($\overline{B}$ 0 → D* + K - ) = (2.22 ± 0.06 ± 0.08) × 10 -4 ; the quoted uncertainties are statistical and systematic, respectively. A measurement of the ratio of these branching fractions is also presented, R K/π = $\mathscr{B}$($\overline{B}$ → D* + K - )/ $\mathscr{B}$($\overline{B}$ → D* + π - ) = (8.41 ± 0.24 ± 0.13) × 10 -2 , where systematic uncertainties due to the D* + meson reconstruction cancel out. Furthermore, we report a new QCD factorization test based on the measured ratios for $\overline{B}$ → D* + h - and $\overline{B}$ → D* + ℓ - $v$ decays at squared momentum transfer values equivalent to the mass of the h = π or K hadron. The parameters |a 1 (h)| are measured to be |a 1 (π)| = 0.884 ± 0.004 ± 0.003 ± 0.016 and |a 1 (K)| = 0.913 ± 0.019 ± 0.008 ± 0.013, where the last uncertainties account for all external inputs. These values are approximately 15% lower than those expected from theoretical predictions. Subsequently, flavor SU(3) symmetry is tested by measuring the ratios for pions and kaons, |a 1 (K)| 2 /|a 1 (π) 2 | = 1.066 ± 0.042 ± 0.018 ± 0.023, as well as for different particle species. The ratio is consistent with unity and therefore no evidence for SU(3) symmetry breaking effects is found at the 5% precision level.

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DOE OSTI2023

Evidence of a New Excited Charmed Baryon Decaying to Σ c ( 2455 ) 0 , + + π ±

We present the study of $\overline{B}$ 0 →Σ c ⁢(2455) 0,++ ⁢π ± $\overline{p}$ decays based on 772×10 6 B$\overline{B}$ events collected with the Belle detector at the KEKB asymmetric-energy e + ⁢e - collider. The Σ c⁢ (2455) 0,++ candidates are reconstructed via their decay to Λ$^{+}_{c}$π ∓ and Λ$^{+}_{c}$ decays to pK ⁢- π + , pK$^{0}_{S}$, and Λ⁢π + final states. The corresponding branching fractions are measured to be $\mathscr{B}$⁡($\overline{B}$ 0 →Σ c ⁢(2455) 0⁢ π + $\overline{p}$)=(1.09±0.06±0.07)×10 -4 and $\mathscr{B}$⁡($\overline{B}$ 0 →Σ c ⁢(2455) ++ ⁢π - ⁢$\overline{p}$)=(1.84±0.11±0.12)×10 -4 , which are consistent with the world average values with improved precision. A new structure is found in the M Σ c (2455) 0,++⁢π± spectrum with a significance of 4.2⁢σ including systematic uncertainty. The structure is possibly an excited Λ$^{+}_{c}$ and is tentatively named Λ c ⁢(2910) + . Its mass and width are measured to be (2913.8±5.6±3.8) MeV/c 2 and (51.8±20.0±18.8) MeV, respectively. The products of branching fractions for the Λ c ⁢(2910) + are measured to be $\mathscr{B}$⁡($\overline{B}$ 0 →Λ c (2910) + $\overline{p}$) × $\mathscr{B}$⁡(Λ c ⁢(2910) + →Σ c ⁢(2455) 0 π + )=(9.5±3.6±1.6) x 10 -6 and $\mathscr{B}$($\overline{B}$ 0 →Λ c ⁢(2910) + ⁢ $\overline{p}$) × $\mathscr{B}$⁡(Λ c (2910) + →Σ c (2455 )++ π - )=(1.24±0.35±0.10)×10 -5 . Here, the first and second uncertainties are statistical and systematic, respectively.

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