arXiv subjects

Zhiqing Zhang

Publications and source records attributed to Zhiqing Zhang.

At least 19 recordsLinked to original sources

arXiv2026

BMW/DMZ calculation of the hadronic vacuum polarisation for the muon magnetic moment

For twenty years, a persistent discrepancy between experimental measurements and theoretical calculations of the muon anomalous magnetic moment have provided tantalising hints of new physics. In recent years, improvements to the experimental precision have appeared to make the tension stronger and stronger. However, at the same time, our lattice calculation overturned the theoretical consensus, completely eliminating the tension. I will present the latest results from the Budapest-Marseille-Wuppertal (BMW) and DMZ collaborations, with a hybrid determination of the hadronic vacuum polarisation contribution to a precision of 0.45%

hep-lat↗

arXiv2026

Overview of tau lepton physics at a super tau-charm facility

An overview of tau lepton physics is presented, using the tau lepton discovery and its precision measurements as examples to illustrate the importance of the energy region to be covered by the super tau-charm factory. By presenting the current measurement status of the major physics topics, the emphasize is put on pointing out a few open issues and possibilities for the super tau-charm factory.

hep-ex↗

arXiv2026

Review of hadronic vacuum polarization calculations via $e^+e^-$ measurements

The discrepancy on the muon anomalous magnetic moment values obtained via a direct measurement and via a data-driven theory determination that uses the experimentally measured hadronic cross section, is among the long standing and most significant deviations from the Standard Model predictions. The recently presented final result of the direct measurement performed at the experiment at Fermilab, with an impressive accuracy of 127 parts-per-billion, further stresses the need for a theory estimate of comparable accuracy. The $e^+e^-$ hadronic cross section is the experimental input to the dispersive integral for the calculation of the hadronic contribution to the $g-2$, which is largely dominated by the $e^+e^-\to π^+π^-$ channel. Precise measurements of the $e^+e^-\to π^+π^-$ cross section with a sub-percent accuracy, in the energy region of the $ρ$-resonance peak, have been performed by several experiments, but the results differ way more than the published accuracies limiting the comparison with the Fermilab direct measurement. New results are expected to become available in the near future from KLOE, CMD-3, SND and BESIII experiments, while a new measurement from the BABAR collaboration is presented today and its impact on the present situation is discussed. This measurement makes use of the entire BABAR data set and adopts a different analysis strategy, with results (still preliminary) largely independent of the results published in the 2009 BABAR publication.

hep-ex↗

arXiv2025

Data-based form factor corrections between the two-pion $τ$ and $e^+e^-$ spectral functions

The $τ$ spectral functions are an alternative to $e^+e^-$ cross-sections, where different measurements are not consistent, for computing the hadronic vacuum contribution to the muon magnetic anomaly $a_μ$. This requires a control of isospin-breaking effects which have to be corrected for. So far these corrections have been evaluated using theoretical models. In this letter, a new approach based only on data is presented for the determination of the most critical correction relating the $e^+e^-$ and $τ$ pion form factors. An updated evaluation of the total isospin-breaking correction is given and its impact is discussed in the context of $e^+e^-$-based $a_μ$ predictions and of the direct measurement.

hep-ph↗

arXiv2025

Three-dimensional neural network driving self-interference digital holography enables high-fidelity, non-scanning volumetric fluorescence microscopy

We present a deep learning driven computational approach to overcome the limitations of self-interference digital holography that imposed by inferior axial imaging performances. We demonstrate a 3D deep neural network model can simultaneously suppresses the defocus noise and improves the spatial resolution and signal-to-noise ratio of conventional numerical back-propagation-obtained holographic reconstruction. Compared with existing 2D deep neural networks used for hologram reconstruction, our 3D model exhibits superior performance in enhancing the resolutions along all the three spatial dimensions. As the result, 3D non-scanning volumetric fluorescence microscopy can be achieved, using 2D self-interference hologram as input, without any mechanical and opto-electronic scanning and complicated system calibration. Our method offers a high spatiotemporal resolution 3D imaging approach which can potentially benefit, for example, the visualization of dynamics of cellular structure and measurement of 3D behavior of high-speed flow field.

physics.optics↗

arXiv2025

Data Preservation in High Energy Physics

Data preservation significantly increases the scientific output of high-energy physics experiments during and after data acquisition. For new and ongoing experiments, the careful consideration of long-term data preservation in the experimental design contributes to improving computational efficiency and strengthening the scientific activity in HEP through Open Science methodologies. This contribution is based on 15 years of experience of the DPHEP collaboration in the field of data preservation and focuses on aspects relevant for the strategic programming of particle physics in Europe: the preparation of future programs using data sets preserved from previous similar experiments (e.g. HERA for EIC), and the use of LHC data long after the end of the data taking. The lessons learned from past collider experiments and recent developments open the way to a number of recommendations for the full exploitation of the investments made in large HEP experiments.

hep-ex↗

arXiv2024

SpineMamba: Enhancing 3D Spinal Segmentation in Clinical Imaging through Residual Visual Mamba Layers and Shape Priors

Accurate segmentation of 3D clinical medical images is critical in the diagnosis and treatment of spinal diseases. However, the inherent complexity of spinal anatomy and uncertainty inherent in current imaging technologies, poses significant challenges for semantic segmentation of spinal images. Although convolutional neural networks (CNNs) and Transformer-based models have made some progress in spinal segmentation, their limitations in handling long-range dependencies hinder further improvements in segmentation accuracy.To address these challenges, we introduce a residual visual Mamba layer to effectively capture and model the deep semantic features and long-range spatial dependencies of 3D spinal data. To further enhance the structural semantic understanding of the vertebrae, we also propose a novel spinal shape prior module that captures specific anatomical information of the spine from medical images, significantly enhancing the model's ability to extract structural semantic information of the vertebrae. Comparative and ablation experiments on two datasets demonstrate that SpineMamba outperforms existing state-of-the-art models. On the CT dataset, the average Dice similarity coefficient for segmentation reaches as high as 94.40, while on the MR dataset, it reaches 86.95. Notably, compared to the renowned nnU-Net, SpineMamba achieves superior segmentation performance, exceeding it by up to 2 percentage points. This underscores its accuracy, robustness, and excellent generalization capabilities.

eess.IV↗

arXiv2023

Introducing Shape Prior Module in Diffusion Model for Medical Image Segmentation

Medical image segmentation is critical for diagnosing and treating spinal disorders. However, the presence of high noise, ambiguity, and uncertainty makes this task highly challenging. Factors such as unclear anatomical boundaries, inter-class similarities, and irrational annotations contribute to this challenge. Achieving both accurate and diverse segmentation templates is essential to support radiologists in clinical practice. In recent years, denoising diffusion probabilistic modeling (DDPM) has emerged as a prominent research topic in computer vision. It has demonstrated effectiveness in various vision tasks, including image deblurring, super-resolution, anomaly detection, and even semantic representation generation at the pixel level. Despite the robustness of existing diffusion models in visual generation tasks, they still struggle with discrete masks and their various effects. To address the need for accurate and diverse spine medical image segmentation templates, we propose an end-to-end framework called VerseDiff-UNet, which leverages the denoising diffusion probabilistic model (DDPM). Our approach integrates the diffusion model into a standard U-shaped architecture. At each step, we combine the noise-added image with the labeled mask to guide the diffusion direction accurately towards the target region. Furthermore, to capture specific anatomical a priori information in medical images, we incorporate a shape a priori module. This module efficiently extracts structural semantic information from the input spine images. We evaluate our method on a single dataset of spine images acquired through X-ray imaging. Our results demonstrate that VerseDiff-UNet significantly outperforms other state-of-the-art methods in terms of accuracy while preserving the natural features and variations of anatomy.

eess.IV↗

arXiv2023

Hadronic vacuum polarization: comparing lattice QCD and data-driven results in systematically improvable ways

The precision with which hadronic vacuum polarization (HVP) is obtained determines how accurately important observables, such as the muon anomalous magnetic moment, a_μ, or the low-energy running of the electromagnetic coupling, α, are predicted. The two most precise approaches for determining HVP are: dispersive relations combined with e+e- to hadrons cross-section data, and lattice QCD. However, the results obtained in these two approaches display significant tensions, whose origins are not understood. Here we present a framework that sheds light on this issue and, if the two approaches can be reconciled, allows them to be combined. Via this framework, we test the hypothesis that the tensions can be explained by modifying the R-ratio in different intervals of center-of-mass energy sqrt(s). As ingredients, we consider observables that have been precisely determined in both approaches. These are the leading hadronic contributions to a_μ, to the so-called intermediate window observable and to the running of αbetween spacelike virtualities 1GeV^2 and 10GeV^2 (for which only a preliminary lattice result exists). Our tests take into account all uncertainties and correlations, as well as uncertainties on uncertainties in the lattice results. Among our findings, the most striking is that results obtained in the two approaches can be made to agree for all three observables by modifying the ρpeak in the experimental spectrum. In particular, we find that this requires a common ~5\% increase in the contributions of the peak to each of the three observables. This finding is robust against the presence or absence of one of the constraining observables. However, such an increase is much larger than the uncertainties on the measured R-ratio. We also discuss a variety of generalizations of the methods used here, as well as the limits in the information that can be extracted...

hep-ph↗

arXiv2022

Proceedings of the Low-$x$ 2021 International Workshop

The purpose of the Low-$x$ Workshop series is to stimulate discussions between experimentalists and theorists in diffractive hadronic physics, QCD dynamics at low $x$, parton saturation, and exciting problems in QCD at HERA, Tevatron, LHC, RHIC, and the future EIC. The central topics of the workshop, summarized in the current Proceedings, were: Diffraction in ep and e-ion collisions (including EIC physics); Diffraction and photon-exchange in hadron-hadron, hadron-nucleus, and nucleus-nucleus collisions; Spin Physics; Low-$x$ PDFs, forward physics, and hadronic final states. This Workshop has been the XXVIII edition in the series of the workshop.

hep-ph↗

arXiv2022

Dispersive approach to HVP for muon g-2

The dispersive approaches to the hadronic vacuum polarisation contributions to the muon anomalous magnetic moment $a_μ$ are described. The main issues are discussed followed by perspectives in the next years.

hep-ph↗

arXiv2021

Determination of Proton Parton Distribution Functions using ATLAS Data

Using differential cross-section data of inclusive $W$ and $Z/γ^\ast$ boson production and of their production in association with jets, and differential cross-section data of top-quark pair production in the lepton + jets and dilepton channels in proton$-$proton collisions at the CERN Large Hadron Collider at center-of-mass energies of $\sqrt{s}=7$ and 8 TeV, together with deep inelastic scattering data from electron$-$proton collisions at the HERA collider, several determinations of parton distribution functions of the proton have been performed by the ATLAS experiment. The results are presented here. The emphasis is given to the determination of the strange sea quark distribution and its evolution over time.

hep-ex↗

arXiv2021

Anomalous reflection at the interface of binary synthetic photonic lattices

We construct a binary synthetic photonic lattice theoretically with an effective magnetic field by projecting two fiber loops' light intensity and adjusting the phase distribution precisely. By tuning the phase modulator, wave vector, and propagation constant of an effective waveguide, the interface's transmittance could be manipulated. Further light dynamics show that the light pulse can achieve total reflection without diffraction and exchanges the light energy in two optical fiber loops completely when phase distribution and wave vector meet certain conditions. Our study may provide a new way to realize optical switches in optical interconnection and optical communication.

physics.optics↗

arXiv2018

Critical behaviors of half-metallic ferromagnet Co3Sn2S2

We have investigated the critical behavior of a shandite-type half-metal ferromagnet Co3Sn2S2. It exhibits a second-order paramagnetic-ferromagnetic phase transition with TC = 174 K. To investigate the nature of the magnetic phase transition, a detailed critical exponent study has been performed. The critical components beta, gamma, and delta determined using the modified Arrott plot, the Kouvel-Fisher method as well as the critical isotherm analysis are match reasonably well and follow the scaling equation, confirming that the exponents are unambiguous and intrinsic to the material. The determined exponents of Co3Sn2S2 deviates from theoretical estimated short-range universal models. Instead, Co3Sn2S2 exhibits long-range order in the nature of magnetic interaction with the spin decay as J(r) ~ 1/r^[-(d + sigma)] with sigma = 1.28.

cond-mat.str-el↗

arXiv2017

Update of the ALEPH non-strange spectral functions from hadronic $τ$ decays

An update of the ALEPH non-strange spectral functions from hadronic $τ$ decays is presented. Compared to the 2005 ALEPH publication, the main improvement is related to the use of a new method to unfold the measured mass spectra from detector effects. This procedure also corrects a previous problem in the correlations between the unfolded mass bins. Results from QCD studies and for the evaluation of the hadronic vacuum polarisation contribution to the anomalous muon magnetic moment are derived using the new spectral functions. They are found in agreement with published results based on the previous set of spectral functions.

hep-ex↗

arXiv2017

Extraction of Top Backgrounds in the Higgs Boson Search with the $H\to WW^\ast \to \ell\ell + E_{\rm T}^{\rm miss}$ Decay with a Full-Jet Veto at the LHC

The search for a Standard Model Higgs boson with the $H\to WW^\ast\to \ell\ell + E_{\rm T}^{\rm miss}$ decay and the application of a full-jet veto yields a strong sensitivity in the mass range $130<m_H<200$ GeV. One of the residual backgrounds is related to processes involving top quarks. A method for the extraction of top backgrounds is evaluated at the parton and hadronic levels based on the data-driven extraction of the jet veto survival probability. The uncertainty of the proposed method is about 15%.

hep-ph↗

arXiv2017

Reevaluation of the hadronic vacuum polarisation contributions to the Standard Model predictions of the muon g-2 and alpha(mZ) using newest hadronic cross-section data

We reevaluate the hadronic vacuum polarisation contributions to the muon magnetic anomaly and to the running of the electromagnetic coupling constant at the Z-boson mass. We include newest e+e- to hadrons cross-section data (among others) from the BABAR and VEPP-2000 experiments. For the muon (g-2)/2 we find for the lowest-order hadronic contribution (693.1 +- 3.4) 10^-10, improving the precision of our previous evaluation by 21%. The full Standard Model prediction differs by 3.5 sigma from the experimental value. The five-quark hadronic contribution to alpha(mZ) is evaluated to be (276.0 +- 0.9) 10^-4.

hep-ph↗

arXiv2016

$Υ(1S)$ ${\to}$ $B_{c}π$, $B_{c}K$ decays with perturbative QCD approach

With the potential prospects of the $Υ(1S)$ at high-luminosity dedicated heavy-flavor factories, the bottom-changing $Υ(1S)$ ${\to}$ $B_{c}π$, $B_{c}K$ weak decays are studied with the pQCD approach. It is found that branching ratio for the color-favored and CKM-favored $Υ(1S)$ ${\to}$ $B_{c}π$ decay can reach up to ${\cal O}(10^{-11})$. So the $Υ(1S)$ ${\to}$ $B_{c}π$ decay might be measured promisingly by the future experiments.

hep-ph↗