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Jianming Bian

Publications and source records attributed to Jianming Bian.

29 records · Page 2Linked to original sources

Research and Development for Near Detector Systems Towards Long Term Evolution of Ultra-precise Long-baseline Neutrino Experiments

With the discovery of non-zero value of $θ_{13}$ mixing angle, the next generation of long-baseline neutrino (LBN) experiments offers the possibility of obtaining statistically significant samples of muon and electron neutrinos and anti-neutrinos with large oscillation effects. In this document we intend to highlight the importance of Near Detector facilities in LBN experiments to both constrain the systematic uncertainties affecting oscillation analyses but also to perform, thanks to their close location, measurements of broad benefit for LBN physics goals. A strong European contribution to these efforts is possible.

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Results and Prospects from NOvA

NOvA is a long-baseline neutrino experiment that uses an upgraded NuMI neutrino source at Fermilab and a 14-kton detector at Ash River, Minnesota. The detector has a highly active, finely segmented design that offers superb event identification capability. This talk presents the latest $ν_μ$ ($\barν_μ$) disappearance and $ν_e$ ($\barν_e$) appearance combined results using the first NOvA anti-neutrino beam data. In the far detector, 18 $\barν_e$ candidate events are observed, with a significance of $\barν_e$ appearance more than 4 $σ$. The NOvA results favor a normal neutrino mass hierarchy.

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Measurement of Neutrino-Electron Elastic Scattering at NOvA Near Detector

NOvA is a long-baseline accelerator-based neutrino oscillation experiment that is optimized for electron-neutrino appearance measurements. It uses the upgraded NuMI beam from Fermilab and consists of a Far Detector in Ash River, Minnesota and a Near Detector at Fermilab. An accurate prediction of the neutrino flux is key to both oscillation and cross-section measurements. The precisely known neutrino-electron elastic scattering cross section provides an in situ constraint on the absolute flux. This talk discusses the status of the measurement of the rate of neutrino-electron elastic scattering in the NOvA Near Detector.

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Recent Results of Electron-Neutrino Appearance Measurement at NOvA

NOvA is a long-baseline accelerator-based neutrino oscillation experiment that is optimized for $ν_e$ measurements. It uses the upgraded NuMI beam from Fermilab and measures electron-neutrino appearance and muon-neutrino disappearance at its Far Detector in Ash River, Minnesota. The $ν_e$ appearance analysis at NOvA aims to resolve the neutrino mass hierarchy problem and to constrain the CP-violating phase. The first measurement of electron-neutrino appearance in NOvA based on its first year's data was produced in 2015, providing solid evidence of $ν_e$ oscillation with the NuMI beam line and some hints on mass-hierarchy and CP. This talk will discuss the second $ν_e$ oscillation analysis at NOvA, which is based on 2 years of data.

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First Results of $ν_e$ Appearance Analysis and Electron Neutrino Identification at NOvA

NOvA is a long-baseline accelerator-based neutrino oscillation experiment that is optimized for $ν_μ\toν_e$ measurements. It uses the upgraded NuMI beam from Fermilab and measures electron-neutrino appearance and muon-neutrino disappearance at its Far Detector in Ash River, Minnesota. The $ν_e$ appearance analysis at NOvA aims to resolve the neutrino mass hierarchy problem and to constrain the CP-violating phase. The first data set of $2.74\times10^{20}$ protons on target (POT) equivalent exposure taken by NOvA has been analyzed. The first measurement of electron-neutrino appearance in NOvA provides solid evidence of $ν_μ\toν_e$ oscillation with the NuMI beam line. Electron-neutrino identification is the key ingredient for the $ν_e$ appearance analysis. The electron-identification algorithm used to produce the primary results presented here compares 3-D shower-energy profiles with Monte Carlo prototypes to construct likelihoods for each particle hypothesis. Particle likelihoods, among other event-topology variables, are used as inputs to an Artificial Neural Network for the final electron-neutrino identification. The design and implementation of this algorithm is also presented.

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Studies of Charmonium-like States at BESIII

In the quark model, hadrons are dominantly bound states of quark-antiquark pairs (mesons) or three quarks (baryons), but QCD also allows hadronic states to be composed of more quarks bound together. Recently, BESIII, Belle and LHCb have confirmed the existence of four-quark and pentaquark candidates. These new states, along with experimentally observed resonances that do not fit well into the charmonium and bottomonium spectra, present challenges and opportunities for strong interaction theory. In this talk, I will review results on charmonium-like exotic quark states that have been observed by the BESIII experiment at the Beijing Electron Positron Collider II (BEPCII).

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The CAPTAIN Experiment

The Cryogenic Apparatus for Precision Tests of Argon Interactions with Neutrinos (CAPTAIN) program is designed to make measurements of scientific importance to long-baseline neutrino physics and physics topics that will be explored by large underground detectors. The experiment employs two liquid Argon time projection chambers (LArTPCs), a primary detector with a mass of approximately 10 ton that will be deployed at different facilities for physics measurements and a two ton prototype detector for configuration testing. The physics programs for CAPTAIN include measuring neutron interactions at the Los Alamos Neutron Science Center, measuring neutrino interactions in the high-energy regime (1.5-5 GeV) at Fermilab NuMI beam, and measuring neutrino interactions in the low-energy regime (<50 MeV) at stopped pion sources for supernova neutrino studies. The prototype detector (Mini-CAPTAIN) has been commissioned and the first UV laser track has been seen in its TPC. This paper gives an overview of the CAPTAIN program and reports the status of the commissioning. The up-to-date detector design and running plans are also described.

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The Long-Baseline Neutrino Experiment: Exploring Fundamental Symmetries of the Universe

The preponderance of matter over antimatter in the early Universe, the dynamics of the supernova bursts that produced the heavy elements necessary for life and whether protons eventually decay --- these mysteries at the forefront of particle physics and astrophysics are key to understanding the early evolution of our Universe, its current state and its eventual fate. The Long-Baseline Neutrino Experiment (LBNE) represents an extensively developed plan for a world-class experiment dedicated to addressing these questions. LBNE is conceived around three central components: (1) a new, high-intensity neutrino source generated from a megawatt-class proton accelerator at Fermi National Accelerator Laboratory, (2) a near neutrino detector just downstream of the source, and (3) a massive liquid argon time-projection chamber deployed as a far detector deep underground at the Sanford Underground Research Facility. This facility, located at the site of the former Homestake Mine in Lead, South Dakota, is approximately 1,300 km from the neutrino source at Fermilab -- a distance (baseline) that delivers optimal sensitivity to neutrino charge-parity symmetry violation and mass ordering effects. This ambitious yet cost-effective design incorporates scalability and flexibility and can accommodate a variety of upgrades and contributions. With its exceptional combination of experimental configuration, technical capabilities, and potential for transformative discoveries, LBNE promises to be a vital facility for the field of particle physics worldwide, providing physicists from around the globe with opportunities to collaborate in a twenty to thirty year program of exciting science. In this document we provide a comprehensive overview of LBNE's scientific objectives, its place in the landscape of neutrino physics worldwide, the technologies it will incorporate and the capabilities it will possess.

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The NOvA Experiment: Overview and Status

The NO$ν$A experiment is a long-baseline accelerator based neutrino oscillation experiment. It uses the upgraded Fermilab NuMI beam and measures electron-neutrino appearance and muon-neutrino disappearance at its far detector in Ash River, Minnesota. Goals of the experiment include measurements of $θ_{13}$, the neutrino-mass hierarchy and the CP-violating phase. NO$ν$A has begun to take data this year and will have its first physics results in 2014. This talk provides an overview of the scientific reach of the NO$ν$A experiment, the status of detector construction and physics analysis and a first glimpse of far-detector data.

physics.ins-det↗

A Review of h_c(1P1), eta_c(1S) and eta_c(2S)

Recent experimental results on charmonium $h_c(^1P_1)$, $η_c(1S)$ and $η_c(2S)$ from Belle, BaBar, CLEO and BESIII are reviewed. $h_c$ production and properties, the $η_c(1S)$ lineshape and the observation of $η_c(2S)$ in $ψ'$ decays are discussed.

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