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Based on 10.64 fb110.64~\mathrm{fb}^{-1} of e+ee^+e^- collision data taken at center-of-mass energies between 4.237 and 4.699 GeV with the BESIII detector, we study the leptonic Ds+D^+_s decays using the e+eDs+Dse^+e^-\to D^{*+}_{s} D^{*-}_{s} process. The branching fractions of Ds++ν(=μ,τ)D_s^+\to\ell^+\nu_{\ell}\,(\ell=\mu,\tau) are measured to be B(Ds+μ+νμ)=(0.547±0.026stat±0.016syst)%\mathcal{B}(D_s^+\to\mu^+\nu_\mu)=(0.547\pm0.026_{\rm stat}\pm0.016_{\rm syst})\% and B(Ds+τ+ντ)=(5.60±0.16stat±0.20syst)%\mathcal{B}(D_s^+\to\tau^+\nu_\tau)=(5.60\pm0.16_{\rm stat}\pm0.20_{\rm syst})\%, respectively. The product of the decay constant and Cabibbo-Kobayashi-Maskawa matrix element Vcs|V_{cs}| is determined to be fDs+Vcs=(246.5±5.9stat±3.6syst±0.5input)μν MeVf_{D_s^+}|V_{cs}|=(246.5\pm5.9_{\rm stat}\pm3.6_{\rm syst}\pm0.5_{\rm input})_{\mu\nu}~\mathrm{MeV} and fDs+Vcs=(252.7±3.6stat±4.5syst±0.6input))τν MeVf_{D_s^+}|V_{cs}|=(252.7\pm3.6_{\rm stat}\pm4.5_{\rm syst}\pm0.6_{\rm input}))_{\tau \nu}~\mathrm{MeV}, respectively. Taking the value of Vcs|V_{cs}| from a global fit in the Standard Model, we obtain fDs+=(252.8±6.0stat±3.7syst±0.6input)μν{f_{D^+_s}}=(252.8\pm6.0_{\rm stat}\pm3.7_{\rm syst}\pm0.6_{\rm input})_{\mu\nu} MeV and fDs+=(259.2±3.6stat±4.5syst±0.6input)τν{f_{D^+_s}}=(259.2\pm3.6_{\rm stat}\pm4.5_{\rm syst}\pm0.6_{\rm input})_{\tau \nu} MeV, respectively. Conversely, taking the value for fDs+f_{D_s^+} from the latest lattice quantum chromodynamics calculation, we obtain Vcs=(0.986±0.023stat±0.014syst±0.003input)μν|V_{cs}| =(0.986\pm0.023_{\rm stat}\pm0.014_{\rm syst}\pm0.003_{\rm input})_{\mu\nu} and Vcs=(1.011±0.014stat±0.018syst±0.003input)τν|V_{cs}| = (1.011\pm0.014_{\rm stat}\pm0.018_{\rm syst}\pm0.003_{\rm input})_{\tau \nu}, respectively.
We present the first experimental evidence for in-ice Askaryan radiation -- coherent charge-excess radio emission -- from high-energy particle cascades developing in the Antarctic ice sheet. In 208 days of data recorded with the phased-array instrument of the Askaryan Radio Array, a previous analysis has incidentally identified 13 events with impulsive radiofrequency signals originating from below the ice surface. We here present a detailed reanalysis of these events. The observed event rate, radiation arrival directions, signal shape, spectral content, and electric field polarization are consistent with in-ice Askaryan radiation from cosmic ray air shower cores impacting the ice sheet. For the brightest events, the angular radiation pattern favors an extended cascade-like emitter over a pointlike source. An origin from the geomagnetic separation of charges in cosmic ray air showers is disfavored by the arrival directions and polarization. Considering the arrival angles, timing properties, and the impulsive nature of the passing events, the event rate is inconsistent with the estimation of the combined background from thermal noise events and on-surface events at the level of 5.1σ5.1\,\sigma.
The prediction of reactor antineutrino spectra will play a crucial role as reactor experiments enter the precision era. The positron energy spectrum of 3.5 million antineutrino inverse beta decay reactions observed by the Daya Bay experiment, in combination with the fission rates of fissile isotopes in the reactor, is used to extract the positron energy spectra resulting from the fission of specific isotopes. This information can be used to produce a precise, data-based prediction of the antineutrino energy spectrum in other reactor antineutrino experiments with different fission fractions than Daya Bay. The positron energy spectra are unfolded to obtain the antineutrino energy spectra by removing the contribution from detector response with the Wiener-SVD unfolding method. Consistent results are obtained with other unfolding methods. A technique to construct a data-based prediction of the reactor antineutrino energy spectrum is proposed and investigated. Given the reactor fission fractions, the technique can predict the energy spectrum to a 2% precision. In addition, we illustrate how to perform a rigorous comparison between the unfolded antineutrino spectrum and a theoretical model prediction that avoids the input model bias of the unfolding method.
Using e+ee^+e^- collision data collected with the BESIII detector operating at the Beijing Electron Positron Collider, the cross section of e+eπ+πhce^+e^-\to \pi^+\pi^- h_c is measured at 59 points with center-of-mass energy s\sqrt{s} ranging from 4.0094.009 to 4.950 GeV4.950~\mathrm{GeV} with a total integrated luminosity of 22.2 fb122.2~\mathrm{fb}^{-1}. The cross section between 4.34.3 and 4.45 GeV4.45~\mathrm{GeV} exhibits a plateau-like shape and drops sharply around 4.5 GeV4.5~\mathrm{GeV}, which cannot be described by two resonances only. Three coherent Breit-Wigner functions are used to parameterize the s\sqrt{s}-dependent cross section line shape. The masses and widths are determined to be M1=(4223.63.72.9+3.6+2.6) MeV/c2M_1=(4223.6_{-3.7-2.9}^{+3.6+2.6})~\mathrm{MeV}/c^2, Γ1=(58.511.46.5+10.8+6.7) MeV\Gamma_1=(58.5_{-11.4-6.5}^{+10.8+6.7})~\mathrm{MeV}, M2=(4327.418.89.3+20.1+10.7) MeV/c2M_2=(4327.4_{-18.8-9.3}^{+20.1+10.7})~\mathrm{MeV}/c^2, Γ2=(244.127.118.3+34.0+24.2) MeV\Gamma_2=(244.1_{-27.1-18.3}^{+34.0+24.2})~\mathrm{MeV}, and M3=(4467.45.42.7+7.2+3.2) MeV/c2M_3=(4467.4_{-5.4-2.7}^{+7.2+3.2})~\mathrm{MeV}/c^2, Γ3=(62.814.47.0+19.2+9.9) MeV\Gamma_3=(62.8_{-14.4-7.0}^{+19.2+9.9})~\mathrm{MeV}. The first uncertainties are statistical and the second are systematic. The inclusion of the relatively narrower third component proves crucial for reproducing the drop at around 4.5~GeV. The statistical significance of the three-resonance assumption over the two-resonance assumption is greater than 5σ5\sigma.
Tohoku University logoTohoku UniversityUniversity of MississippiUniversity of CincinnatiNational United UniversityKyungpook National UniversityHiroshima Institute of TechnologyINFN Sezione di NapoliCharles UniversityNational Central UniversityChinese Academy of Sciences logoChinese Academy of SciencesBudker Institute of Nuclear Physics SB RASGyeongsang National UniversityTel Aviv University logoTel Aviv UniversityKorea UniversityUniversity of Science and Technology of China logoUniversity of Science and Technology of ChinaChonnam National UniversityIndiana UniversitySungkyunkwan UniversityNational Taiwan UniversityUniversity of BonnPanjab UniversityNagoya University logoNagoya UniversityUniversity of TabukUniversity of MelbourneIndian Institute of Technology BhubaneswarUniversity of LjubljanaYonsei UniversityPeking University logoPeking UniversityUniversity of Florida logoUniversity of FloridaPacific Northwest National LaboratoryUniversity of Tokyo logoUniversity of TokyoUniversité Paris-Saclay logoUniversité Paris-SaclayTechnionShandong University logoShandong UniversityÉcole Polytechnique Fédérale de Lausanne (EPFL)University of Sydney logoUniversity of SydneyNovosibirsk State UniversityHanyang UniversityWayne State UniversityHigh Energy Accelerator Research Organization (KEK)Indian Institute of Technology MadrasKitasato UniversityKarlsruhe Institute of Technology logoKarlsruhe Institute of TechnologyUniversity of LouisvilleMoscow Institute of Physics and TechnologyUniversity of MariborUniversity of South CarolinaTokyo Metropolitan UniversitySOKENDAI (The Graduate University for Advanced Studies)University of Eastern FinlandJozef Stefan InstituteDongguk UniversityINFN, Sezione di TorinoNihon UniversityIndian Institute of Technology GuwahatiIndian Institute of Technology HyderabadUniversità di Napoli Federico IIInha UniversityUniversity of Hawai’iKanagawa UniversityMax-Planck-Institut für PhysikCNRS/IN2P3Yamagata UniversityInstitute of high-energy PhysicsLudwig-Maximilian-UniversityJustus Liebig University GiessenKumamoto UniversityKonkuk UniversityDeutsches Elektronen SynchrotronUniversity of ToyamaChristopher Newport UniversityMalaviya National Institute of Technology JaipurUniversity of MiyazakiUniversity of South AlabamaUniversity of Southern MississippiLiaoning Normal UniversityUniversity of California at Santa BarbaraToho UniversityUniversity of GiessenNara University of EducationNara Women’s UniversityP.N. Lebedev Physical Institute of the Russian Academy of SciencesH. Niewodniczanski Institute of Nuclear PhysicsKobayashi-Maskawa Institute for the Origin of Particles and the Universe,Kinki UniversityNihon Dental CollegeNippon Dental UniversityNational Institute of Science Education and Research, HBNIJ-PARCNational Museum of Nature and ScienceKawasaki Medical SchoolOsaka-city UniversityIndian Institute of Science Education and Research −KolkataUniversit Clermont Auvergne
Charged lepton flavor violation is forbidden in the Standard Model but possible in several new physics scenarios. In many of these models, the radiative decays τ±±γ\tau^{\pm}\rightarrow\ell^{\pm}\gamma (=e,μ\ell=e,\mu) are predicted to have a sizeable probability, making them particularly interesting channels to search at various experiments. An updated search via τ±±γ\tau^{\pm}\rightarrow\ell^{\pm}\gamma using full data of the Belle experiment, corresponding to an integrated luminosity of 988 fb1^{-1}, is reported for charged lepton flavor violation. No significant excess over background predictions from the Standard Model is observed, and the upper limits on the branching fractions, B(τ±μ±γ)\mathcal{B}(\tau^{\pm}\rightarrow \mu^{\pm}\gamma) \leq 4.2×1084.2\times10^{-8} and B(τ±e±γ)\mathcal{B}(\tau^{\pm}\rightarrow e^{\pm}\gamma) \leq 5.6×1085.6\times10^{-8}, are set at 90\% confidence level.
In an era where cultural preservation is increasingly intertwined with technological innovation, this study introduces a groundbreaking approach to promoting and safeguarding the rich heritage of Taiwanese Hakka culture through the development of a Retrieval-Augmented Generation (RAG)-enhanced chatbot. Traditional large language models (LLMs), while powerful, often fall short in delivering accurate and contextually rich responses, particularly in culturally specific domains. By integrating external databases with generative AI models, RAG technology bridges this gap, empowering chatbots to not only provide precise answers but also resonate deeply with the cultural nuances that are crucial for authentic interactions. This study delves into the intricate process of augmenting the chatbot's knowledge base with targeted cultural data, specifically curated to reflect the unique aspects of Hakka traditions, language, and practices. Through dynamic information retrieval, the RAG-enhanced chatbot becomes a versatile tool capable of handling complex inquiries that demand an in-depth understanding of Hakka cultural context. This is particularly significant in an age where digital platforms often dilute cultural identities, making the role of culturally aware AI systems more critical than ever. System usability studies conducted as part of our research reveal a marked improvement in both user satisfaction and engagement, highlighting the chatbot's effectiveness in fostering a deeper connection with Hakka culture. The feedback underscores the potential of RAG technology to not only enhance user experience but also to serve as a vital instrument in the broader mission of ethnic mainstreaming and cultural celebration.
With many endangered languages at risk of disappearing, efforts to preserve them now rely more than ever on using technology alongside culturally informed teaching strategies. This study examines user behaviors in TALKA, a generative AI-powered chatbot designed for Hakka language engagement, by employing a dual-layered analytical framework grounded in Bloom's Taxonomy of cognitive processes and dialogue act categorization. We analyzed 7,077 user utterances, each carefully annotated according to six cognitive levels and eleven dialogue act types. These included a variety of functions, such as asking for information, requesting translations, making cultural inquiries, and using language creatively. Pragmatic classifications further highlight how different types of dialogue acts--such as feedback, control commands, and social greetings--align with specific cognitive intentions. The results suggest that generative AI chatbots can support language learning in meaningful ways--especially when they are designed with an understanding of how users think and communicate. They may also help learners express themselves more confidently and connect with their cultural identity. The TALKA case provides empirical insights into how AI-mediated dialogue facilitates cognitive development in low-resource language learners, as well as pragmatic negotiation and socio-cultural affiliation. By focusing on AI-assisted language learning, this study offers new insights into how technology can support language preservation and educational practice.
We report a measurement of electron antineutrino oscillation from the Daya Bay Reactor Neutrino Experiment with nearly 4 million reactor νe\overline{\nu}_{e} inverse beta decay candidates observed over 1958 days of data collection. The installation of a Flash-ADC readout system and a special calibration campaign using different source enclosures reduce uncertainties in the absolute energy calibration to less than 0.5% for visible energies larger than 2 MeV. The uncertainty in the cosmogenic 9^9Li and 8^8He background is reduced from 45% to 30% in the near detectors. A detailed investigation of the spent nuclear fuel history improves its uncertainty from 100% to 30%. Analysis of the relative νe\overline{\nu}_{e} rates and energy spectra among detectors yields sin22θ13=0.0856±0.0029\sin^{2}2\theta_{13} = 0.0856\pm 0.0029 and $\Delta m^2_{32}=(2.471^{+0.068}_{-0.070})\times 10^{-3}~\mathrm{eV}^2$ assuming the normal hierarchy, and $\Delta m^2_{32}=-(2.575^{+0.068}_{-0.070})\times 10^{-3}~\mathrm{eV}^2$ assuming the inverted hierarchy.
We present measurements of B+ -> Dbar*0 tau+ nu_tau and B+ -> Dbar^0 tau+ nu_tau decays in a data sample of 657 x 10^6 BBbar pairs collected with the Belle detector at the KEKB asymmetric-energy e+e- collider. We find 446^{+58}_{-56} events of the decay B+ -> Dbar*0 tau+ nu_tau with a significance of 8.1 standard deviations, and 146^{+42}_{-41} events of the decay B+ -> Dbar0 tau+ nu_tau with a significance of 3.5 standard deviations. The latter signal provides the first evidence for this decay mode. The measured branching fractions are B(B+ -> Dbar*0 tau+ nu_tau)=(2.12^{+0.28}_{-0.27} (stat) +- 0.29 (syst)) % and B(B+ -> Dbar0 tau+ nu_tau)=(0.77 +- 0.22 (stat) +- 0.12 (syst)) %.
This Letter reports an improved search for light sterile neutrino mixing in the electron antineutrino disappearance channel with the full configuration of the Daya Bay Reactor Neutrino Experiment. With an additional 404 days of data collected in eight antineutrino detectors, this search benefits from 3.6 times the statistics available to the previous publication, as well as from improvements in energy calibration and background reduction. A relative comparison of the rate and energy spectrum of reactor antineutrinos in the three experimental halls yields no evidence of sterile neutrino mixing in the 2×104Δm4120.32\times10^{-4} \lesssim |\Delta m^{2}_{41}| \lesssim 0.3 eV2^{2} mass range. The resulting limits on sin22θ14\sin^{2}2\theta_{14} are improved by approximately a factor of 2 over previous results and constitute the most stringent constraints to date in the Δm4120.2|\Delta m^{2}_{41}| \lesssim 0.2 eV2^{2} region.
This paper introduces VoxHakka, a text-to-speech (TTS) system designed for Taiwanese Hakka, a critically under-resourced language spoken in Taiwan. Leveraging the YourTTS framework, VoxHakka achieves high naturalness and accuracy and low real-time factor in speech synthesis while supporting six distinct Hakka dialects. This is achieved by training the model with dialect-specific data, allowing for the generation of speaker-aware Hakka speech. To address the scarcity of publicly available Hakka speech corpora, we employed a cost-effective approach utilizing a web scraping pipeline coupled with automatic speech recognition (ASR)-based data cleaning techniques. This process ensured the acquisition of a high-quality, multi-speaker, multi-dialect dataset suitable for TTS training. Subjective listening tests conducted using comparative mean opinion scores (CMOS) demonstrate that VoxHakka significantly outperforms existing publicly available Hakka TTS systems in terms of pronunciation accuracy, tone correctness, and overall naturalness. This work represents a significant advancement in Hakka language technology and provides a valuable resource for language preservation and revitalization efforts.
This study introduces a comprehensive benchmark designed to evaluate the performance of large language models (LLMs) in understanding and processing cultural knowledge, with a specific focus on Hakka culture as a case study. Leveraging Bloom's Taxonomy, the study develops a multi-dimensional framework that systematically assesses LLMs across six cognitive domains: Remembering, Understanding, Applying, Analyzing, Evaluating, and Creating. This benchmark extends beyond traditional single-dimensional evaluations by providing a deeper analysis of LLMs' abilities to handle culturally specific content, ranging from basic recall of facts to higher-order cognitive tasks such as creative synthesis. Additionally, the study integrates Retrieval-Augmented Generation (RAG) technology to address the challenges of minority cultural knowledge representation in LLMs, demonstrating how RAG enhances the models' performance by dynamically incorporating relevant external information. The results highlight the effectiveness of RAG in improving accuracy across all cognitive domains, particularly in tasks requiring precise retrieval and application of cultural knowledge. However, the findings also reveal the limitations of RAG in creative tasks, underscoring the need for further optimization. This benchmark provides a robust tool for evaluating and comparing LLMs in culturally diverse contexts, offering valuable insights for future research and development in AI-driven cultural knowledge preservation and dissemination.
This Letter reports the first measurement of the oscillation amplitude and frequency of reactor antineutrinos at Daya Bay via neutron capture on hydrogen using 1958 days of data. With over 3.6 million signal candidates, an optimized candidate selection, improved treatment of backgrounds and efficiencies, refined energy calibration, and an energy response model for the capture-on-hydrogen sensitive region, the relative νe\overline{\nu}_{e} rates and energy spectra variation among the near and far detectors gives sin22θ13=0.07590.0049+0.0050\mathrm{sin}^22\theta_{13} = 0.0759_{-0.0049}^{+0.0050} and Δm322=(2.720.15+0.14)×103\Delta m^2_{32} = (2.72^{+0.14}_{-0.15})\times10^{-3} eV2^2 assuming the normal neutrino mass ordering, and Δm322=(2.830.14+0.15)×103\Delta m^2_{32} = (-2.83^{+0.15}_{-0.14})\times10^{-3} eV2^2 for the inverted neutrino mass ordering. This estimate of sin22θ13\sin^2 2\theta_{13} is consistent with and essentially independent from the one obtained using the capture-on-gadolinium sample at Daya Bay. The combination of these two results yields sin22θ13=0.0833±0.0022\mathrm{sin}^22\theta_{13}= 0.0833\pm0.0022, which represents an 8% relative improvement in precision regarding the Daya Bay full 3158-day capture-on-gadolinium result.
University of MississippiUniversity of CincinnatiNational United UniversityCharles UniversityNational Central UniversityNiigata UniversityChinese Academy of Sciences logoChinese Academy of SciencesBudker Institute of Nuclear Physics SB RASKorea UniversityBeihang University logoBeihang UniversityIndiana UniversityNational Taiwan UniversityNagoya University logoNagoya UniversityUniversity of MelbourneIndian Institute of Technology BhubaneswarUniversity of LjubljanaINFN logoINFNPacific Northwest National LaboratoryUniversity of the Basque Country (UPV/EHU)École Polytechnique Fédérale de Lausanne (EPFL)Novosibirsk State UniversityHanyang UniversityHigh Energy Accelerator Research Organization (KEK)Indian Institute of Technology MadrasMoscow Institute of Physics and TechnologyKennesaw State UniversityUniversity of MariborKing Abdulaziz UniversitySOKENDAI (The Graduate University for Advanced Studies)Indian Institute of Technology HyderabadUniversity of Hawai’iKanagawa UniversityIKERBASQUE-Basque Foundation for ScienceIndian Institute of Science Education and Research (Mohali)Ludwig Maximilians UniversityJ. Stefan InstituteInstitute of High Energy Physics, ViennaKorea Institute of Science and Technology InformationKing Abdulaziz City for Science and TechnologyKarlsruher Institut fur TechnologieUniversity of Nova GoricaP.N. Lebedev Physical Institute of the Russian Academy of SciencesH. Niewodniczanski Institute of Nuclear PhysicsInstitute for High Energy Physics ProtvinoMax-Planck Institut f•ur PhysikMoscow Physical Engineering InstituteAdvanced Science Research Center, Japan Atomic Energy AgencyOsaka-city University
We search for CPCP violation in the charged charm meson decay D+π+π0D^{+}\to\pi^{+}\pi^{0}, based on a data sample corresponding to an integrated luminosity of 921 fb1\rm 921~fb^{-1} collected by the Belle experiment at the KEKB e+ee^{+}e^{-} asymmetric-energy collider. The measured CPCP violating asymmetry is [+2.31±1.24(stat)±0.23(syst)]%[+2.31\pm1.24({\rm stat})\pm0.23({\rm syst})]\%, which is consistent with the standard model prediction and has a significantly improved precision compared to previous results.
The dark photon, AA^\prime, and the dark Higgs boson, hh^\prime, are hypothetical constituents featured in a number of recently proposed Dark Sector Models. Assuming prompt decays of both dark particles, we search for their production in the so-called Higgs-strahlung channel, e+eAhe^+e^- \rightarrow A^\prime h', with hAAh^\prime \rightarrow A^\prime A^\prime. We investigate ten exclusive final-states with Ae+eA^\prime \rightarrow e^+e^-, μ+μ\mu^+\mu^-, or π+π\pi^+\pi^-, in the mass ranges 0.10.1~GeV/c2c^2~< m_{A^\prime} < 3.5~GeV/c2c^2 and 0.20.2~GeV/c2c^2~< m_{h'} < 10.5~GeV/c2c^2. We also investigate three inclusive final-states, 2(e+e)X2(e^+e^-)X, 2(μ+μ)X2(\mu^+\mu^-)X, and (e+e)(μ+μ)X(e^+e^-)(\mu^+\mu^-)X, where XX denotes a dark photon candidate detected via missing mass, in the mass ranges 1.11.1~GeV/c2c^2~< m_{A^\prime} < 3.5~GeV/c2c^2 and 2.22.2~GeV/c2c^2~< m_{h'} < 10.5~GeV/c2c^2. Using the entire 977fb1977\,\mathrm{fb}^{-1} data set collected by Belle, we observe no significant signal. We obtain individual and combined 90%\% confidence level upper limits on the branching fraction times the Born cross section, B×σBorn\cal B \times \sigma_{\mathrm{Born}}, on the Born cross section, σBorn\sigma_{\mathrm{Born}}, and on the dark photon coupling to the dark Higgs boson times the kinetic mixing between the Standard Model photon and the dark photon, αD×ϵ2\alpha_D \times \epsilon^2. These limits improve upon and cover wider mass ranges than previous experiments. The limits from the final-states 3(π+π)3(\pi^+\pi^-) and 2(e+e)X2(e^+e^-)X are the first placed by any experiment. For αD\alpha_D equal to 1/137, m_{h'}< 8 GeV/c2c^2, and m_{A^\prime}< 1 GeV/c2c^2, we exclude values of the mixing parameter, ϵ\epsilon, above 8×104\sim 8 \times 10^{-4}.
We report a high-statistics measurement of the branching fraction for tau^- --> pi^- pi^0 nu_tau and the invariant mass spectrum of the produced pi^- pi^0 system using 72.2 fb^-1 of data recorded with the Belle detector at the KEKB asymmetric-energy e^+ e^- collider. The branching fraction obtained is (25.24 +/- 0.01 +/- 0.39)%, where the first error is statistical and the second is systematic. The unfolded pi^- pi^0 mass spectrum is used to determine resonance parameters for the rho(770), rho'(1450), and rho"(1700) mesons. We also use this spectrum to estimate the hadronic (2pi) contribution to the anomalous magnetic moment of the muon (a_{mu}^{pipi}). Our result for a_{mu}^{pipi} integrated over the mass range sqrt{s} = 2m_{pi} - 1.8 GeV/c^2 is a_{mu}^{pipi} = (523.5 +/- 1.5 (exp) +/- 2.6 (Br) +/- 2.5 (isospin))x 10^{-10}, where the first error is due to the experimental uncertainties, the second is due to the uncertainties in the branching fractions and the third is due to the uncertainties in the isospin-violating corrections.
Age-related macular degeneration (AMD) is the leading cause of visual impairment among elderly in the world. Early detection of AMD is of great importance, as the vision loss caused by this disease is irreversible and permanent. Color fundus photography is the most cost-effective imaging modality to screen for retinal disorders. Cutting edge deep learning based algorithms have been recently developed for automatically detecting AMD from fundus images. However, there are still lack of a comprehensive annotated dataset and standard evaluation benchmarks. To deal with this issue, we set up the Automatic Detection challenge on Age-related Macular degeneration (ADAM), which was held as a satellite event of the ISBI 2020 conference. The ADAM challenge consisted of four tasks which cover the main aspects of detecting and characterizing AMD from fundus images, including detection of AMD, detection and segmentation of optic disc, localization of fovea, and detection and segmentation of lesions. As part of the challenge, we have released a comprehensive dataset of 1200 fundus images with AMD diagnostic labels, pixel-wise segmentation masks for both optic disc and AMD-related lesions (drusen, exudates, hemorrhages and scars, among others), as well as the coordinates corresponding to the location of the macular fovea. A uniform evaluation framework has been built to make a fair comparison of different models using this dataset. During the challenge, 610 results were submitted for online evaluation, with 11 teams finally participating in the onsite challenge. This paper introduces the challenge, the dataset and the evaluation methods, as well as summarizes the participating methods and analyzes their results for each task. In particular, we observed that the ensembling strategy and the incorporation of clinical domain knowledge were the key to improve the performance of the deep learning models.
The differential cross sections for the process $\gamma \gamma \to \pi^0 \pi^0havebeenmeasuredinthekinematicrange0.6GeV have been measured in the kinematic range 0.6 GeV < W < 4.1$ GeV, |\cos \theta^*|&lt;0.8 in energy and pion scattering angle, respectively, in the γγ\gamma\gamma center-of-mass system. The results are based on a 223 fb1^{-1} data sample collected with the Belle detector at the KEKB e+ee^+ e^- collider. The differential cross sections are fitted in the energy region 1.7 GeV &lt; W &lt; 2.5 GeV to confirm the two-photon production of two pions in the G wave. In the higher energy region, we observe production of the χc0\chi_{c0} charmonium state and obtain the product of its two-photon decay width and branching fraction to π0π0\pi^0\pi^0. We also compare the observed angular dependence and ratios of cross sections for neutral-pion and charged-pion pair production to QCD models. The energy and angular dependence above 3.1 GeV are compatible with those measured in the π+π\pi^+\pi^- channel, and in addition we find that the cross section ratio, σ(π0π0)/σ(π+π)\sigma(\pi^0\pi^0)/\sigma(\pi^+\pi^-), is $0.32 \pm 0.03 \pm 0.05$ on average in the 3.1-4.1 GeV region.
We search for lepton-flavor-violating tau-> ell V^0 decays, where ell is an electron or muon and V^0 is one of the vector mesons rho^0, phi, omega, K*0 and K*0-bar. We use 854 fb^{-1} of data collected with the Belle detector at the KEKB asymmetric-energy e^+e^- collider. No evidence for a signal is found in any decay mode, and we obtain 90% confidence level upper limits on the individual branching fractions in the range (1.2-8.4)*10^{-8}.
National United UniversityCharles UniversityNational Central UniversityChinese Academy of Sciences logoChinese Academy of SciencesSichuan UniversitySun Yat-Sen University logoSun Yat-Sen UniversityUniversity of Science and Technology of China logoUniversity of Science and Technology of ChinaBeihang University logoBeihang UniversityNational Taiwan UniversityNanjing University logoNanjing UniversityTsinghua University logoTsinghua UniversityNankai UniversityJoint Institute for Nuclear ResearchJilin UniversityShandong University logoShandong UniversityXiangtan UniversitySoochow UniversityTechnische Universität MünchenUniversity of HamburgAix Marseille UniversityUniversità degli Studi di PaviaUniversity of JyväskyläUniversity of AlabamaINFN, Sezione di PaviaDongguan University of TechnologyUniversità degli Studi di BolognaXian Jiaotong UniversityINFN, Laboratori Nazionali di FrascatiEberhard-Karls-Universität TübingenNorth China Electric Power UniversityComenius UniversityINFN, Sezione di MilanoInstitute of high-energy PhysicsChina Institute of Atomic EnergyINFN - Sezione di PadovaUniversità degli Studi di CataniaInstitute for Nuclear Research, Russian Academy of SciencesKing Mongkut’s Institute of Technology LadkrabangPalacký UniversityParis-Saclay UniversityINFN, Sezione di CataniaINFN-Sezione di BolognaUniversitá dell’InsubriaUniversità degli Studi di Roma TreSkobeltsyn Institute of Nuclear Physics, Moscow State UniversityZhongshan UniversityDaya Bay Nuclear Power Joint LaboratoryLAPP, Université Savoie Mont Blanc, CNRS/IN2P3INFN-Sezione di Roma TreINFN-Sezione di FerraraUniversit degli Studi di GenovaUniversit degli Studi di PerugiaUniversit Libre de BruxellesUniversit degli Studi di PadovaNational Research Nuclear University ","MEPhIRWTH Aachen University
JUNO is a massive liquid scintillator detector with a primary scientific goal of determining the neutrino mass ordering by studying the oscillated anti-neutrino flux coming from two nuclear power plants at 53 km distance. The expected signal anti-neutrino interaction rate is only 60 counts per day, therefore a careful control of the background sources due to radioactivity is critical. In particular, natural radioactivity present in all materials and in the environment represents a serious issue that could impair the sensitivity of the experiment if appropriate countermeasures were not foreseen. In this paper we discuss the background reduction strategies undertaken by the JUNO collaboration to reduce at minimum the impact of natural radioactivity. We describe our efforts for an optimized experimental design, a careful material screening and accurate detector production handling, and a constant control of the expected results through a meticulous Monte Carlo simulation program. We show that all these actions should allow us to keep the background count rate safely below the target value of 10 Hz in the default fiducial volume, above an energy threshold of 0.7 MeV.
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