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At least 55 records · Page 3

Searches for exclusive Higgs boson decays into D *$\gamma$ and Z boson decays into D 0 $\gamma$ and K $^{0}_{s}$$\gamma$ in pp collisions at $\sqrt{s}$ = 13 TeV with the ATLAS detector

Searches for exclusive decays of the Higgs boson into D*$\gamma$ and of the Z boson into D 0 $\gamma$ and K$_{s}^{0}$$\gamma$ can probe flavour-violating Higgs boson and Z boson couplings to light quarks. Searches for these decays are performed with a pp collision data sample corresponding to an integrated luminosity of 136.3 fb -1 collected at $\sqrt{s}$ = 13TeV between 2016–2018 with the ATLAS detector at the CERN Large Hadron Collider. In the D*$\gamma$ and D 0 $\gamma$ channels, the observed (expected) 95% confidence-level upper limits on the respective branching fractions are B(H→D*$\gamma$) < 1.0(1.2)×10 -3 , B(Z→D 0 $\gamma$) < 4.0(3.4)×10 -6 , while the corresponding results in the K$_{s}^{0}$$\gamma$ channel are B(Z→K$_{s}^{0}$$\gamma$) < 3.1(3.0)×10 -6 .

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS

Measurement of the branching fraction of Λ + 𝑐 →𝑝⁢𝐾 0 𝑆⁢ 𝜋 0 at Belle

We report a precise measurement of the ratio of branching fractions ℬ⁡(Λ$^+_𝑐$ → 𝑝⁢𝐾$^0_𝑆$⁢𝜋 0 )/ℬ⁡(Λ$^+_𝑐$ → 𝑝⁢𝐾 − ⁢𝜋 + ) using 980 fb −1 of 𝑒 + ⁢𝑒 − data from the Belle experiment. We obtain a value of ℬ⁡(Λ$^+_𝑐$ → 𝑝⁢𝐾$^0_𝑆$⁢𝜋 0 )/ℬ⁡(Λ$^+_𝑐$ → 𝑝⁢𝐾 − ⁢𝜋 + ) =0.339 ±0.002 ±0.009, where the first and second uncertainties are statistical and systematic, respectively. This Belle result is consistent with the previous measurement from the CLEO experiment but has a fivefold improvement in precision. By combining our result with the world average ℬ⁡(Λ$^+_𝑐$ → 𝑝⁢𝐾 − ⁢𝜋 + ), we obtain the absolute branching fraction ℬ⁡(Λ$^+_𝑐$ → 𝑝⁢𝐾$^0_𝑆$⁢𝜋 0 ) =(2.12 ± 0.01 ±0.05 ±0.10)%, where the uncertainties are statistical, systematic, and the uncertainty in the absolute branching fraction scale ℬ⁡(Λ$^+_𝑐$ → 𝑝⁢𝐾 − ⁢𝜋 + ), respectively. This measurement can shed light on hadronic decay mechanisms in charmed baryon decays.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS

First Exclusive Reconstruction of the 𝐵* + , 𝐵* 0 , and 𝐵$^{*0}_{𝑠}$ Mesons and Precise Measurement of Their Masses

Using proton-proton collision data collected by the CMS experiment at √𝑠 = 13 TeV in 2016–2018, corresponding to an integrated luminosity of 140 fb −1 , the first full reconstruction of the three vector 𝐵 meson states, 𝐵* + , 𝐵* 0 , and 𝐵$^{*0}_{𝑠}$, is performed. The mass differences between the excited mesons and their corresponding ground states are measured to be 𝑚⁡(𝐵* + )−𝑚⁡(𝐵 + ) = 45.277 ± 0.039 ± 0.027 MeV, 𝑚⁡(𝐵 *0 )−𝑚⁡(𝐵 0 ) = 45.471 ± 0.056 ± 0.028 MeV, and 𝑚⁡(𝐵$^{*0}_{𝑠}$)−𝑚⁡(𝐵$^{0}_{𝑠}$) = 49.407 ± 0.132 ± 0.041 MeV, where the first uncertainties are statistical and the second are systematic. These results improve on the precision of previous measurements by an order of magnitude.

Bottom mesons

Measurement of the branching fractions of the decays Λ c + → Λ K S 0 K + , Λ c + → Λ K S 0 π + , and Λ c + → Λ K * +

Studies are performed of the Cabibbo-favored decay Λ c + → Λ K S 0 K + and the singly Cabibbo-suppressed decay Λ c + → Λ K S 0 π + , based on a sample of e + e − collision data, corresponding to an integrated luminosity of 4.5 fb − 1 , accumulated at center-of-mass energies between 4599.53 MeV and 4698.82 MeV with the BESIII detector. The decay Λ c + → Λ K S 0 π + is observed for the first time. The branching fractions of Λ c + → Λ K S 0 K + and Λ c + → Λ K S 0 π + are measured to be ( 3.04 ± 0.30 ± 0.16 ) × 10 − 3 and ( 1.73 ± 0.27 ± 0.10 ) × 10 − 3 , respectively, where the first uncertainties are statistical and the second are systematic. These results correspond to the most precise measurement of these quantities for both decays. Evidence of a K * + contribution in the Λ c + → Λ K S 0 π + decay is found with a statistical significance of 4.71 σ . The branching fraction of Λ c + → Λ K * + is calculated under three possible interference scenarios, with the significance increasing to 5.03 σ when interference is taken into account. Published by the American Physical Society 2025

Ablikim, M.

Study of light-meson resonances decaying to K S 0 K π in the B → ( K S 0 K π ) K channels

A study is presented of B + → K S 0 K − π + K + and B + → K S 0 K + π − K + decays based on the analysis of proton-proton collision data collected with the LHCb detector at center-of-mass energies of 7, 8 and 13 TeV, corresponding to an integrated luminosity of 9 fb − 1 . The K S 0 K π invariant-mass distributions of both B + decay modes show, in the m ( K S 0 K π ) < 1.85 GeV mass region, large activity which is resolved using an amplitude analysis. A simple model, where J P C amplitudes are described by multiple Breit-Wigner functions with appropriate angular distributions, provides a good description of the experimental data. In this approach a complex mixture of J P C = 0 − + , 1 + + and 1 + − amplitudes is observed that is dominated by η ( 1405 ) , η ( 1470 ) , η ( 1760 ) , f 1 ( 1285 ) , f 1 ( 1420 ) and h 1 ( 1405 ) resonances. The K S 0 K π Dalitz plots are dominated by asymmetric crossing K * K ¯ bands which are different for the two B + decay modes. This is due to a different interference pattern between the 1 + + and 1 + − amplitudes in the two channels. Branching fractions are measured for each resonant contribution. © 2025 CERN, for the LHCb Collaboration 2025 CERN

Aaij, R. (ORCID:0000000305331952)

Study of D s + → f 0 ( 980 ) ρ + and ϕ π + Decays through D s + → π + π + π − π 0

We perform the first amplitude analysis of D s + → π + π + π − π 0 decays based on data samples of electron-positron collisions recorded with the BESIII detector at center-of-mass energies between 4.128 and 4.226 GeV, corresponding to an integrated luminosity of 7.33 fb − 1 . We report the observation of D s + → f 0 ( 980 ) ρ ( 770 ) + with a statistical significance greater than 10 σ and determine the branching fractions B ( D s + → π + π + π − π 0 | non − η ) = ( 2.04 ± 0.0 8 stat ± 0.0 5 syst ) % and B ( D s + → η π + ) = ( 1.56 ± 0.0 9 stat ± 0.0 4 syst ) % . Moreover, we measure the relative branching fraction between ϕ → π + π − π 0 and ϕ → K + K − to be [ B ( ϕ ( 1020 ) → π + π − π 0 ) / B ( ϕ ( 1020 ) → K + K − ) ] = 0.230 ± 0.01 4 stat ± 0.01 0 syst ., which deviates from the world average value by more than 4 σ . Published by the American Physical Society 2025

Ablikim, M.

Search for the Higgs boson decays to a ρ 0 , ϕ, or K ⁎0 meson and a photon in proton-proton collisions at $\sqrt{s} = 13$ TeV

Three rare decay processes of the Higgs boson to a ρ(770) 0 , Φ(1020), or K ⁎ (892) 0 meson and a photon are searched for using $\sqrt{s} = 13$ TeV proton-proton collision data collected by the CMS experiment at the LHC. Events are selected assuming the mesons decay into a pair of charged pions, a pair of charged kaons, or a charged kaon and pion, respectively. Depending on the Higgs boson production mode, different triggering and reconstruction techniques are adopted. The analyzed data sets correspond to integrated luminosities up to 138 fb -1 , depending on the reconstructed final state. After combining various data sets and categories, no significant excess above the background expectations is observed. Upper limits at 95% confidence level on the Higgs boson branching fractions into ρ(770) 0 $γ$, Φ(1020)$γ$, and K ⁎ (892) 0 are determined to be 3.7 x 10 -4 , 3.0 x 10 -4 , and 3.0 x 10 -4 , respectively. In case of the ρ(770) 0 $γ$ and Φ(1020)$γ$ channels, these are the most stringent experimental limits to date.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS

Observation of the decays 𝐵 + → Σ 𝑐 ⁢(2455) ++ $\bar{Ξ}^-_c$ and 𝐵 0 → Σ 𝑐 ⁢(2455) 0⁢ $\bar{Ξ}^0_𝑐$

We report the first observation of the two-body baryonic decays 𝐵 + → Σ 𝑐 ⁢(2455) ++ $\bar{Ξ}^-_c$ and 𝐵 0 → Σ 𝑐 ⁢(2455) 0⁢ $\bar{Ξ}^0_𝑐$ with significances of 7.3⁢𝜎 and 6.2⁢𝜎, respectively, including statistical and systematic uncertainties. The branching fractions are measured to be ℬ⁡(𝐵 + → Σ 𝑐 ⁢(2455) ++ $\bar{Ξ}^-_c$) = (5.74 ± 1.11 ± 0.4⁢2$^{+2.47}_{−1.53}$) ×10 −4 and ℬ⁡(𝐵 0 → Σ 𝑐 ⁢(2455) 0⁢ $\bar{Ξ}^0_𝑐$) = (4.83 ± 1.12 ± 0.3⁢7$^{+0.72}_{−0.60}$) ×10 −4 . The first and second uncertainties are statistical and systematic, respectively, while the third ones arise from the absolute branching fractions of $\bar{Ξ}^-_c$ or $\bar{Ξ}^0_𝑐$ decays. The data samples used for this analysis have integrated luminosities of 711 fb −1 and 365 fb −1 , and were collected at the ϒ⁡(4⁢𝑆) resonance by the Belle and Belle II detectors operating at the KEKB and SuperKEKB asymmetric-energy 𝑒 + ⁢𝑒 − colliders, respectively.

branching fraction

Search for D 0 → K − η e + ν e , D + → K S 0 η e + ν e and D + → η η e + ν e decays

By analyzing e + e − annihilation data corresponding to an integrated luminosity of 7.93 fb − 1 , collected at the center-of-mass energy of 3.773 GeV with the BESIII detector, we search for the semileptonic decays D 0 → K − η e + ν e , D + → K S 0 η e + ν e and D + → η η e + ν e for the first time. We present evidence for D 0 → K − η e + ν e with a significance of 3.3 σ . The branching fraction of D 0 → K − η e + ν e is measured to be ( 0.8 4 − 0.34 + 0.29 ± 0.22 ) × 10 − 4 . No significant signals are observed for the decays D + → K S 0 η e + ν e and D + → η η e + ν e and we set the upper limits on their branching fractions. Published by the American Physical Society 2024

Ablikim, M.

Search for two-body B meson decays to Λ 0 and Ω c ( * ) 0

We report the results of the first search for Standard Model and baryon-number-violating two-body decays of the neutral B mesons to Λ 0 and Ω c ( * ) 0 using 711 fb − 1 of data collected at the ϒ ( 4 S ) resonance with the Belle detector at the KEKB asymmetric-energy e + e − collider. We observe no evidence of signal from any such decays and set 95% confidence-level upper limits on the products of B 0 and B ¯ 0 branching fractions for these two-body decays with B ( Ω c 0 → π + Ω − ) in the range between 9.5 × 10 − 8 and 31.2 × 10 − 8 . Published by the American Physical Society 2024

Savinov, V. (ORCID:0000000291842830)

Observation of the W -Annihilation Process D s + → ω ρ + and Measurement of D s + → ϕ ρ + in D s + → π + π + π − π 0 π 0 Decays

We present the first amplitude analysis and branching fraction measurement of the decay D s + → π + π + π − π 0 π 0 , using e + e − collision data collected with the BESIII detector at center-of-mass energies between 4.128 and 4.226 GeV corresponding to an integrated luminosity of 7.33 fb − 1 , and report the first observation of the pure W -annihilation decay D s + → ω ρ + with a branching fraction of ( 0.99 ± 0.0 8 stat − 0.07 + 0.05 syst ) % . In comparison to the low significance of the D wave in the decay D s + → ϕ ρ + , the dominance of the D wave over the S and P waves, with a fraction of ( 51.85 ± 7.2 8 stat − 7.90 + 4.83 syst ) % observed in the decay D s + → ω ρ + , provides crucial information for the “polarization puzzle,” as well as for the understanding of charm meson decays. The branching fraction of D s + → π + π + π − π 0 π 0 is measured to be ( 4.41 ± 0.1 5 stat ± 0.1 3 syst ) % . Moreover, the branching fraction of D s + → ϕ ρ + is measured to be ( 3.98 ± 0.3 3 stat − 0.19 + 0.21 syst ) % , and the R ϕ = B ( ϕ → π + π − π 0 ) / B ( ϕ → K + K − ) is determined to be ( 0.222 ± 0.01 9 stat − 0.016 + 0.016 syst ), which is consistent with the previous measurement based on charm meson decays, but deviates from the results from e + e − annihilation and K − N scattering experiments by more than 3 σ . Published by the American Physical Society 2025

Ablikim, M.

Search for lepton flavor-violating decay modes B 0 → K* 0 τ ± ℓ ∓ (ℓ = e, μ) with hadronic B-tagging at Belle and Belle II

We present the results of a search for the charged-lepton-flavor violating decays B 0 → K *0 τ ± ℓ ∓ , where ℓ ∓ is either an electron or a muon. The results are based on 365 fb −1 and 711 fb −1 datasets collected with the Belle II and Belle detectors, respectively. We use an exclusive hadronic B-tagging technique, and search for a signal decay in the system recoiling against a fully reconstructed B meson. We find no evidence for B 0 → K* 0 τ ± ℓ ∓ decays and set upper limits on the branching fractions in the range of (2.9–6.4)×10 −5 at 90% confidence level.

B physics

Measurement of the $B^0_\mathrm{s}\to J/\psi K^0_\mathrm{S}$ effective lifetime from proton-proton collisions at $\sqrt{s} = 13$ TeV

The effective lifetime of the $ {\textrm{B}}_{\textrm{s}}^0 $ meson in the decay $ {\textrm{B}}_{\textrm{s}}^0\to \textrm{J}/{\uppsi \textrm{K}}_{\textrm{S}}^0 $ is measured using data collected during 2016–2018 with the CMS detector in $ \sqrt{s} $ = 13 TeV proton-proton collisions at the LHC, corresponding to an integrated luminosity of 140 fb$^{−1}$. The effective lifetime is determined by performing a two-dimensional unbinned maximum likelihood fit to the $ {\textrm{B}}_{\textrm{s}}^0 $ meson invariant mass and proper decay time distributions. The resulting value of 1.59 ± 0.07(stat) ± 0.03(syst) ps is the most precise measurement to date and is in good agreement with the expected value.[graphic not available: see fulltext]

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS

Observation of time-dependent C P violation and measurement of the branching fraction of B 0 → J / ψ π 0 decays

We present a measurement of the branching fraction and time-dependent charge-parity ( C P ) decay-rate asymmetries in B 0 → J / ψ π 0 decays. The data sample was collected with the Belle II detector at the SuperKEKB asymmetric e + e − collider in 2019–2022 and contains ( 387 ± 6 ) × 10 6 B B ¯ meson pairs from ϒ ( 4 S ) decays. We reconstruct 392 ± 24 signal decays and fit the C P parameters from the distribution of the proper-decay-time difference of the two B mesons. We measure the branching fraction to be ( B 0 → J / ψ π 0 ) = ( 2.00 ± 0.12 ± 0.09 ) × 10 − 5 and the direct and mixing-induced C P asymmetries to be C C P = 0.13 ± 0.12 ± 0.03 and S C P = − 0.88 ± 0.17 ± 0.03 , respectively, where the first uncertainties are statistical and the second are systematic. We observe mixing-induced C P violation with a significance of 5.0 standard deviations for the first time in this mode. Published by the American Physical Society 2025

Adachi, I. (ORCID:0000000322870173)

Search for Lepton-Flavor-Violating Decay Modes 𝐵 0 →𝐾$^0_𝑆$⁢𝜏 ± ⁢ℓ ∓ with Hadronic 𝐵 Tagging at Belle and Belle II

We present the first search for the lepton-flavor-violating decay modes 𝐵 0 →𝐾$^0_𝑆$⁢𝜏 ± ⁢ℓ ∓ (ℓ=𝜇,𝑒) using the 711 and 365 fb −1 data samples recorded by the Belle and Belle II detectors, respectively. We use a hadronic 𝐵-tagging technique to fully reconstruct a 𝐵 meson and search for signal decays in the system recoiling against the tagged meson, considering 𝜏 decays to either light leptons, one charged hadron, or one charged hadron and a neutral pion. We find no evidence for 𝐵 0 →𝐾$^0_𝑆$⁢𝜏 ± ⁢ℓ ∓ decays and set 90% confidence level upper limits on the branching fractions in the range of [0.8,3.6] ×10 −5 .

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS

Terrestrial laser scanning data (Levels 0 and 1) for Pasoh, Malaysia, Sep 2024

This data package contains data from terrestrial laser scanning (TLS) at the Pasoh Forest Reserve, Malaysia. The Pasoh Forest Reserve is a facility of the Forest Research Institute Malaysia, and contains evergreen lowland dipterocarp forest. The Next-Generation Ecosystem Experiments Tropics (NGEE-Tropics) study areas at Pasoh were established to study how different species respond to climatic variation and soil water availability. Two study areas were chosen representing different topography and species. The TLS data archived here were collected to provide detailed, three-dimensional information about forest structure. Specifically, data were collected to allow tree-level characterization of woody structure and leaf area for 12 focal trees with FloraPulse and sap flux sensors, facilitating estimation of woody biomass and leaf area to allow upscaling of water content and transpiration data to the tree-level. Scan positions were not selected to provide consistent data for non-focal trees with the study areas. This data package contains the following data: - High-level files document further details of the campaign and data package: 1_CampaignSummary.csv provides details about the campaign and study site, 2_ScanAreasDetail.csv provides details about each separate scan area (groups of scans post-processed into a single point cloud), 3_TerrestrialLidarSensor.csv provides further technical details about the Riegl VZ-400i TLS sensor, TLS_CSV_dd.csv is a CSV Data Dictionary providing information about the fields in CSV files following the ESS-DIVE CSV File Formatting Guidelines Reporting Format, TLS_flmd.csv is a File Level Metadata file providing information about each file in the data package following the ESS-DIVE File Level Metadata Reporting Format, and README.txt is a text file describing the overall project and file structure. - Level 0 data are the raw data (.PROJ folders) as recorded by the Riegl VZ-400i TLS instrument before scan co-registration and post-processing with the Riegl's proprietary RiSCAN PRO software, which requires a license. - Level 1 data contain post-processed, co-registered data from each scan area. The "PointClouds" folder for each scan area contains a .las file with 1 cm resolution point cloud data exported from RiSCAN PRO. These are the main files likely to be of interest to most users and can be further processed with any software capable of manipulating .las files (e.g. Python, R CloudCompare). The "Project Information" folder contains log files from post-processing in RiSCAN PRO that may be of interest to users who want to see detailed records of post-processing, including all PDF reports generated by RiSCAN PRO. The "ScanPositions" folder contains information about the final position of all TLS scans, after post-processing, in multiple formats. The file ScanPositions_*.csv provides final geo-referenced scan positions, and the file SOP_backup_*.csv can be used in RiSCAN PRO to restore the co-registered scan positions if users wish to re-process raw data (Level 0 .PROJ folders) with RiSCAN PRO software (e.g., subsample to a different resolution, exclude a certain scan position, or apply different filters on reflectance or deviation values) without redoing time-consuming co-registration steps.

54 ENVIRONMENTAL SCIENCES

Terrestrial laser scanning data (Levels 0 and 1) from Urban Biogeochemistry Pilot Project sites, Knoxville, Tennessee, Jul 2024 - Jul 2025

This data package contains data from terrestrial laser scanning (TLS) at five urban park sites in Knoxville, Tennessee, USA. All parks include open-grown and/or closed-canopy trees and mixed nearby land use. These study sites were established as part of the Urban Biogeochemistry Pilot Project, which has an overall goal of better understanding how hydrobiogeochemical cycling is altered within the human environment. These five sites represent a gradient of urbanization, and were instrumented to understand hydrological and biogeochemical cycling (e.g., soil moisture, soil physical properties and biogeochemistry, tree transpiration, species type). The TLS data archived here were collected to provide detailed, three-dimensional information about forest structure. Specifically, data were collected to allow tree- and stand-level characterization of woody structure and leaf area. TLS scans were placed to capture the area around trees with sap flow sensors, and as much of a 50 m radius area around the meteorological station as possible given site property limits. Derived products will allow upscaling of water content and transpiration data. This data package contains the following data: - High-level files document further details of the campaign and data package: 1_CampaignSummary.csv provides details about the campaign and study site, 2_ScanAreasDetail.csv provides details about each separate scan area (groups of scans post-processed into a single point cloud), 3_TerrestrialLidarSensor.csv provides further technical details about the Riegl VZ-400i TLS sensor, TLS_CSV_dd.csv is a CSV Data Dictionary providing information about the fields in CSV files following the ESS-DIVE CSV File Formatting Guidelines Reporting Format, TLS_flmd.csv is a File Level Metadata file providing information about each file in the data package following the ESS-DIVE File Level Metadata Reporting Format, and README.txt is a text file describing the overall project and file structure. - Level 0 data are the raw data (.PROJ folders) as recorded by the Riegl VZ-400i TLS instrument before scan co-registration and post-processing with the Riegl's proprietary RiSCAN PRO software, which requires a license. - Level 1 data contain post-processed, co-registered data from each scan area. The "PointClouds" folder for each scan area contains a .las file with 1 cm resolution point cloud data exported from RiSCAN PRO. These are the main files likely to be of interest to most users and can be further processed with any software capable of manipulating .las files (e.g. Python, R CloudCompare). The "Project Information" folder contains log files from post-processing in RiSCAN PRO that may be of interest to users who want to see detailed records of post-processing, including all PDF reports generated by RiSCAN PRO. The "ScanPositions" folder contains information about the final position of all TLS scans, after post-processing, in multiple formats. The file ScanPositions_*.csv provides final geo-referenced scan positions, and the file SOP_backup_*.csv can be used in RiSCAN PRO to restore the co-registered scan positions if users wish to re-process raw data (Level 0 .PROJ folders) with RiSCAN PRO software (e.g., subsample to a different resolution, exclude a certain scan position, or apply different filters on reflectance or deviation values) without redoing time-consuming co-registration steps.

54 ENVIRONMENTAL SCIENCES