New Signature of low mass Z′Z^\prime in J/ψJ/\psi decays

We explore a new approach to search for a low-mass $Z^{\prime}$ particle through $J/\psi$ decays by identifying its existence through parity-violating phenomena in the isospin-violating final states of $\Lambda\overline{\Sigma}^{0}$ and the corresponding charge conjugated states of $\overline{\Lambda}\Sigma^{0}$. Our investigation centers on a generation-independent and leptophobic $Z^{\prime}$ with its mass below 10 GeV. Given the present experimental conditions at the Beijing Spectrometer III~(BESIII) and the anticipated opportunities at the Super Tau Charm Factory~(STCF), we conduct Monte-Carlo simulations to predict possible events at both facilities. Our simulations indicate that BESIII experiments hold the potential to detect $Z^{\prime}$ signals in $J/\psi\to\Lambda\overline{\Sigma}^{0}$ if the polarization asymmetry paramter $\alpha_{\text{NP}}$ attains a minimum threshold of 0.02. Notably, we foresee a substantial enhancement in the precision of the lower limit estimation of $\alpha_{\text{NP}}$ as well as a reduction in statistical uncertainty with upcoming STCF experiments. Furthermore, it is essential to highlight that a null result in the measurement of $\alpha_{\text{NP}}$ would impose stringent constraints, requiring the $Z^{\prime}$ coupling to be on the order of $10^{-2}$.Comment: 9 pages, 3 figure

Isospin violating decays of vector charmonia

We study the isospin violating decays of vector charmonia to $\Lambda\overline{\Sigma}^0$ and $\rho^{0}\omega^{0}$. They are dominated by the single photon annihilation and can be evaluated reliably with timelike form factors. We utilize the quark-pair creation model, which is valid for the OZI suppressed decays, to evaluate the form factors. We obtain the branching fractions of ${\cal B}(J/\psi\to\Lambda\overline{\Sigma}^0+c.c.)=(2.4\pm0.4)\times10^{-5}$ and ${\cal B}(\psi(2S)\to\Lambda\overline{\Sigma}^0+c.c.)=(3.0\pm0.5)\times10^{-6}$, which are compatible with the measurements by the BESIII collaborations, respectively. The decay asymmetries are found to be $\alpha_{J/\psi}=0.314$ and $\alpha_{\psi(2S)}=0.461$. We predict the branching fractions for mesonic final states as ${\cal B}(J/\psi\to\rho^0\omega^0)=(4.04\pm0.31)\times10^{-3}$ and ${\cal B}(\psi(2S)\to\rho^0\omega^0)=(5.1\pm0.4)\times10^{-4}$, and the corresponding decay asymmetries as $\alpha_{J/\psi}=0.148$ and $\alpha_{\psi(2S)}=0.313$, which can be examined at BESIII in the foreseeable future.Comment: 14 pages, 3 figure

Efficient Non-Learning Similar Subtrajectory Search

Similar subtrajectory search is a finer-grained operator that can better capture the similarities between one query trajectory and a portion of a data trajectory than the traditional similar trajectory search, which requires the two checked trajectories are similar to each other in whole. Many real applications (e.g., trajectory clustering and trajectory join) utilize similar subtrajectory search as a basic operator. It is considered that the time complexity is O(mn^2) for exact algorithms to solve the similar subtrajectory search problem under most trajectory distance functions in the existing studies, where m is the length of the query trajectory and n is the length of the data trajectory. In this paper, to the best of our knowledge, we are the first to propose an exact algorithm to solve the similar subtrajectory search problem in O(mn) time for most of widely used trajectory distance functions (e.g., WED, DTW, ERP, EDR and Frechet distance). Through extensive experiments on three real datasets, we demonstrate the efficiency and effectiveness of our proposed algorithms.Comment: VLDB 202

Crop residue management and fertilization effects on soil organic matter and associated biological properties

Returning crop residue may result in nutrient reduction in soil in the first few years. A two-year field experiment was conducted to assess whether this negative effect is alleviated by improved crop residue management (CRM). Nine treatments (3 CRM and 3 N fertilizer rates) were used. The CRM treatments were (1) R0: 100 % of the N using mineral fertilizer with no crop residues return; (2) R: crop residue plus mineral fertilizer as for the R0; and (3) Rc: crop residue plus 83 % of the N using mineral and 17 % manure fertilizer. Each CRM received N fertilizer rates at 270, 360, and 450 kg N ha−1 year−1. At the end of the experiment, soil NO3-N was reduced by 33 % from the R relative to the R0 treatment, while the Rc treatment resulted in a 21 to 44 % increase in occluded particulate organic C and N, and 80 °C extracted dissolved organic N, 19 to 32 % increase in microbial biomass C and protease activity, and higher monounsaturated phospholipid fatty acid (PLFA):saturated PLFA ratio from stimulating growth of indigenous bacteria when compared with the R treatment. Principal component analysis showed that the Biolog and PLFA profiles in the three CRM treatments were different from each other. Overall, these properties were not influenced by the used N fertilizer rates. Our results indicated that application of 17 % of the total N using manure in a field with crop residues return was effective for improving potential plant N availability and labile soil organic matter, primarily due to a shift in the dominant microorganisms