38323494
Search for the Lepton Flavor Violation Process J/ψ→eμ at BESIII
We search for the lepton-flavor-violating decay of the J/psi into an electron and a muon using (225.3 +/- 2.8) x 10(6) J/psi events collected with the BESIII detector at the BEPCII. Four candidate events are found in the signal region, consistent with background expectations. An upper limit on the branching fraction of B(J/psi -> e mu) <1.6 x 10(-7) (90% C.L.) is obtained.
7332532
Spectral measurement of electron antineutrino oscillation amplitude and frequency at Daya Bay.
A measurement of the energy dependence of antineutrino disappearance at the Daya Bay reactor neutrino experiment is reported. Electron antineutrinos (ν¯(e)) from six 2.9  GW(th) reactors were detected with six detectors deployed in two near (effective baselines 512 and 561 m) and one far (1579 m) underground experimental halls. Using 217 days of data, 41 589 (203 809 and 92 912) antineutrino candidates were detected in the far hall (near halls). An improved measurement of the oscillation amplitude sin(2)2θ(13)=0.090(-0.009)(+0.008) and the first direct measurement of the ν¯(e) mass-squared difference |Δm(ee)2|=(2.59(-0.20)(+0.19))×10(-3)  eV2 is obtained using the observed ν¯(e) rates and energy spectra in a three-neutrino framework. This value of |Δm(ee)2| is consistent with |Δm(μμ)2| measured by muon neutrino disappearance, supporting the three-flavor oscillation model.
125575431
Measurement of the branching ratios for J / psi --> gamma pi0, gamma eta, gamma eta' --> 3gamma on the BES
10500157
Search for a light sterile neutrino at Daya Bay.
A search for light sterile neutrino mixing was performed with the first 217 days of data from the Daya Bay Reactor Antineutrino Experiment. The experiment's unique configuration of multiple baselines from six 2.9 GW(th) nuclear reactors to six antineutrino detectors deployed in two near (effective baselines 512 m and 561 m) and one far (1579 m) underground experimental halls makes it possible to test for oscillations to a fourth (sterile) neutrino in the 10(-3) eV(2)<|Δm(41)(2) |< 0.3 eV(2) range. The relative spectral distortion due to the disappearance of electron antineutrinos was found to be consistent with that of the three-flavor oscillation model. The derived limits on sin(2) 2θ(14) cover the 10(-3) eV(2) ≲ |Δm(41)(2)| ≲ 0.1 eV(2) region, which was largely unexplored.
125590985
Experimental study of f0(975) in J / psi decays
125493400
The sigma pole in J / psi ---> omega pi+ pi-
119216012
Dielectron and diphoton channels in 2HDM
Abstract It was observed recently that [L. Randall, Mark B. Wise, arXiv: 0807.1746 [hep-ph] ], any particle in the Standard Model cannot decay to e + e − and γγ final states with comparably measurable branching ratios. This is also true for most extensions of the Standard Model, with the Randall–Sundrum model as an outstanding exception. In this Letter, we show that two-Higgs-Doublet-Models (2HDM) yield another possible exception if certain parameters are properly chosen. In addition, we have checked that this model survives the tests of low energy processes, including the anomalous magnetic moment and electric dipole moment of leptons, lepton-flavor-violating decays μ − → e − γ and e − e + e − .
119213332
Gauge-singlet dark matter in a left-right symmetric model with spontaneous CP violation
We propose a dark matter (DM) scenario in an extension of a left-right symmetric model with a gauge-singlet scalar field. The gauge-singlet scalar can automatically become a DM candidate, provided that both P and CP symmetries are only broken spontaneously. Thus no extra discrete symmetries are needed to make the DM candidate stable. After constraining the model parameters from the observed relic DM density we make predictions for direct detection experiments. We show that for some parameter range, the predicted weakly interacting massive particle-nucleon elastic scattering cross section can reach the current experimental upper bound, which can be tested by the experiments in the near future.
119173786
Higgs-pair production in littlest Higgs model with T parity
The Higgs-pair production process at the CERN Large Hadron Collider, which will provide a way to test the Higgs boson self-coupling, may be sensitive to new physics. In the framework of the littlest Higgs model with T parity, such Higgs-pair production can proceed through additional loop diagrams, and thus the production rate can be quite different from the standard model prediction. Our calculations show that, due to the loop contributions of both T-even and T-odd quarks predicted in this model, the production rate can be significantly enhanced relative to the standard model prediction and also can be larger than the production rate in the minimal supersymmetric model. Also, we find that the T-odd quark contributions, which were not included in a previous study, are equally important compared with the T-even quark contributions.
53638902
Creating perturbations from a decaying field during inflation
Typically the fluctuations generated from a decaying field during inflation do not contribute to the large scale structures. In this paper we provide an example where it is possible for a field which slowly rolls and then decays during inflation to create all the matter perturbations with a slightly red-tilted spectral index, with no isocurvature perturbations, and with a possibility of a departure from Gaussian fluctuations.
119209933
Higgs boson production in photon-photon collision at ILC: a comparative study in different little Higgs models
We study the process $ \gamma \gamma \to h \to b\bar b $ at ILC as a probe of different little Higgs models, including the simplest little Higgs model (SLH), the littlest Higgs model (LH), and two types of littlest Higgs models with T-parity (LHT-I, LHT-II). Compared with the Standard Model (SM) prediction, the production rate is found to be sizably altered in these little Higgs models and, more interestingly, different models give different predictions. We find that the production rate can be possibly enhanced only in the LHT-II for some part of the parameter space, while in all other cases the rate is suppressed. The suppression can be 10% in the LH and as much as 60% in both the SLH and the LHT-I/LHT-II. The severe suppression in the SLH happens for a large tan β and a small mh, in which the new decay mode h → ηη (η is a light pseudo-scalar) is dominant; while for the LHT-I/LHT-II the large suppression occurs when f and mh are both small so that the new decay mode h → AHAH is dominant. Therefore, the precision measurement of such a production process at the ILC will allow for a test of these models and even distinguish between different scenarios.