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Impact of a nearby subhalo on the constraint of dark matter annihilation from cosmic ray antiprotons

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Chinese Physics C 2024年第2期48卷 175-182页

作者：赵熠毕效军林苏杰殷鹏飞 College of Physics and Materials Science Tianjin Normal UniversityTianjin 300387China Key Laboratory of Particle Astrophysics Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China School of Physical Sciences University of Chinese Academy of SciencesBeijing 100049China Zhuhai Campus of Sun Yat-Sen University Sun Yat-Sen UniversityZhuhai 519082China

Numerous simulations indicate that a large number of subhalos should be hosted by the Milky *** potential existence of a nearby subhalo could have important implications for our understanding of dark matter(DM)*** this study,we investigate the hypothetical presence of a nearby subhalo and set the upper limits on the DM annihilation cross section by analyzing the cosmic-ray antiproton *** presenting the ratios of annihilation cross section limits for scenarios with and without a nearby subhalo,we can quantitatively evaluate the potential impact of the nearby subhalo on the limits of the DM annihilation cross *** impacts of the concentration model and the subhalo probability distribution have been *** explore the antiproton contribution of the potential nearby DM subhalo accounting for the DAMPE e+spectrum at~1.4 TeV and find that the current AMS-02 antiproton results do not limit this contribution.

关键词： dark matter antiproton subhalo

Searching for axion-like particles with the blazar observations of MAGIC and Fermi-LAT

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Chinese Physics C 2022年第8期46卷 262-272页

作者： Hai-jun Li xiao-jun bi Peng-Fei Yin Center for Advanced Quantum Studies Department of PhysicsBeijing Normal UniversityBeijing 100875China Key Laboratory of Particle Astrophysics Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China School of Physics University of Chinese Academy of SciencesBeijing 100049China

In this study,we explore the axion-like particle(ALP)-photon oscillation effect in the γ-ray spectra of the blazars Markarian 421(Mrk 421) and PG 1553+113,which are measured by the Major Atmospheric Gamma Imaging Cherenkov Telescopes(MAGIC) and Fermi Large Area Telescope(Fermi-LAT) with high *** Mrk421 and PG 1553+113 observations of 15 and five phases are used in the analysis,*** find that the combined analysis with all the 15 phases improves the limits of the Mrk 421 *** the selected blazar jet magnetic field and extragalactic background light models,the combined limit set by the Mrk 421 observations excludes the ALP parameter region with the ALP-photon coupling of g_(aγ)≥2×10^(-11) GeV^(-1) for the ALP mass of~8×10^(-9)≤m_(a)≤2×10^(-7) eV at 95% confidence *** main uncertainties of the analysis originate from the blazar jet magnetic field *** also find that the ALP hypothesis can slightly improve the fit to the PG1553+113 results in several parameter *** do not set the limit in this case.

关键词： axion γ-ray blazar

Galactic cosmic ray propagation: sub-PeV diffuse gamma-ray and neutrino emission

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Frontiers of physics 2022年第6期17卷 5-14页

作者： bing-Qiang Qiao Wei Liu Meng-Jie Zhao xiao-jun bi Yi-Qing Guo Key Laboratory of Particle Astrophysics Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China University of Chinese Academy of Sciences Beijing 100049China

The Tibet ASγexperiment just reported their measurement of sub-PeV diffuse gamma-ray emission from the Galactic disk,with the highest energy up to 957 *** diffuse gamma rays are most likely the hadronic origin by cosmic ray(CR)interaction with interstellar gas in the *** measurement provides direct evidence to the hypothesis that the Galactic Cosmic Rays(GCRs)can be accelerated beyond PeV *** this work,we try to explain the sub-PeV diffuse gamma-ray spectrum with different CR propagation *** find that there is a tension between the sub-PeV diffuse gamma-ray and the local CR *** describe the sub-PeV diffuse gamma-ray flux,it generally requires larger local CR flux than measurement in the knee *** further calculate the PeV neutrino flux from the CR propagation *** all of these sub-PeV diffuse gamma rays originate from the propagation,the Galactic Neutrinos(GNs)only account for less than∼15%of observed flux,most of which are still from extragalactic sources.

关键词： Galactic cosmic ray diffuse gamma ray neutrino

Intrinsic Wave Velocity Propagation:A Novel Parameter for Assessing the Effect of Anthracycline Chemotherapy Agents on Cardiac Diastolic Function in Breast Cancer Patients

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Current Medical Science 2023年第6期43卷 1229-1237页

作者： xiao HUANG Xin-ying FAN Qiao CHENG jun ZHANG Jie SUN Qiao-ying TANG You-bin DENG xiao-jun bi Department of Medical Ultrasound Tongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan430030China

Objective Anthracycline chemotherapeutic agents have significant *** present study emphasized the effect of anthracycline chemotherapy drugs on left ventricular(LV)myocardial stiffness in breast cancer patients by measuring the intrinsic wave velocity propagation(IVP),and evaluating the potential clinical value of IVP in detecting early LV diastolic function *** A total of 68 newly diagnosed breast cancer patients,who were treated with anthracycline-based chemotherapy,were *** echocardiography was performed at baseline(T0),and after 1,2,3,4 and 8 chemotherapeutic cycles(T1,T2,T3,T4 and T5,respectively).Then,the IVP,LV strain parameters[global longitudinal strain(GLS),longitudinal peak strain rate at systole(LSRs),longitudinal peak strain rate at early diastole(LSRe),longitudinal peak strain rate at late diastole(LSRa),and the E/LSRe ratio],and conventional echocardiographic parameters were obtained and further analyzed.A relative reduction of>15%in GLS was considered a marker of early LV subclinical *** Compared to the T0 stage,IVP significantly increased at the T1 ***,there were no significant changes in GLS,LSRs,or LSRe between the T0 and T1 *** parameters significantly decreased from the T2 *** started to significantly decrease at the T5 stage,and the E/LSRe ratio started to significantly increase at the T3 stage(all P<0.05).At the T0 stage,IVP(AUC=0.752,P<0.001)had a good predictive value for LV subclinical dysfunction after *** IVP is a potentially sensitive parameter for the early clinical assessment of anthracycline-related cardiac diastolic impairment.

关键词： breast cancer anthracycline chemotherapy drugs intrinsic wave velocity propagation myocardial stiffness cardiac diastolic function

基于Transformer的网络流量预测研究

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信息技术 2024年第4期48卷 156-160页

作者：田爱宝魏娇娇肖军弼中国石油大学(华东)信息化建设处山东青岛266580 中国石油大学(华东)计算机科学与技术学院山东青岛266580

网络流量预测是网络流量分析领域中亟待解决的关键任务之一。现基于机器学习的预测方法大多忽略了流量的长相关性,并且处理大量数据时耗时长。针对以上问题,文中将Transformer用于网络流量预测,通过多头注意力机制捕获流量的远程序列关... 详细信息

网络流量预测是网络流量分析领域中亟待解决的关键任务之一。现基于机器学习的预测方法大多忽略了流量的长相关性,并且处理大量数据时耗时长。针对以上问题,文中将Transformer用于网络流量预测,通过多头注意力机制捕获流量的远程序列关系,学习流量的全局依赖关系。实验结果表明,该方法可以提高预测精度,并能有效降低训练时间。

关键词：流量预测 Transformer 深度学习注意力机制特征提取

Evaluation of Left Ventricular Function by Three-Dimensional Speckle-Tracking Echocardiography in Patients with Chronic Kidney Failure

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Current Medical Science 2022年第4期42卷 895-901页

作者： Yu-bo WANG Hui HUANG Shan LIN Mei-jia HAO Lu-jiao HE Kun LIU xiao-jun bi Department of Ultrasound Third People's Hospital of Hubei ProvinceJianghan UniversityWuhan 430033China Department of Ultrasound Maternal and Child Health Hospital of Hubei ProvinceTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430070China Department of Ultrasound Tongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430030China

Objective:To establish a quantitative evaluation of the left ventricle's systolic function in patients with chronic kidney failure(CKF)by three-dimensional speckle-tracking ***:Two-dimensional and three-dimensional transthoracic echocardiography was performed on 30 patients with *** ejection fraction,mass and global peak longitudinal strain,global circumferential strain,global area strain,and global radial strain of the left ventricle were ***:The ejection fraction,mass and global peak longitudinal strain(GLS),global circumferential strain(GCS),global area strain(GAS),and global radial strain(GRS)in the CKF group were significantly lower than those in the control ***,the GLS,GCS,GAS and GRS were well correlated with the ejection *** patients with normal ejection fraction in the CKF group,the GLS,GCS,GAS and GRS were lower than those in the control group,while the left ventricular mass was significantly higher in CKF patients than in the control *** patients with hypertension in the CKF group,ejection fraction,GLS,GCS,GAS and GRS calculated using three-dimensional echocardiography were significantly lower than those in patients with normal blood pressure;however,the myocardial mass was ***:The parameters(GLS,GCS,GAS and GRS)calculated using three-dimensional speckle-tracking software were lower in the CKF ***,the left ventricular mass was higher in CFK patients than in the control group,thus showing that the myocardial contraction function was impaired and that myocardial remodeling had occurred.

关键词： three-dimensional speckle-tracking echocardiography left ventricle ejection fraction strain chronic kidney failure

Exploring fermionic multiplet dark matter through precision measurements at the CEPC

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Chinese Physics C 2022年第9期46卷 159-172页

作者： Lin-Qing Gao xiao-jun bi Jin-Wei Wang Qian-Fei Xiang Peng-Fei Yin Key Laboratory of Particle Astrophysics Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China School of Physical Sciences University of Chinese Academy of SciencesBeijing 100049China Scuola Internazionale Superiore di Studi Avanzati(SISSA) via Bonomea 26534136 TriesteItaly INFN Sezione di Triestevia Valerio 234127 TriesteItaly Institute for Fundamental Physics of the Universe(IFPU) via Beirut 234151 TriesteItaly Center for High Energy Physics Peking UniversityBeijing 100871China

New physics could be explored through loop effects using the precision measurements at the Circular Electron Positron Collider(CEPC)owing to its clean collision environment and high *** this paper,we focus on two dark matter models that involve additional electroweak fermionic *** calculate their one-loop corrections in five processes,i.e.,e^(+)e^(-)→μ^(+)μ^(-),Zh,W^(+)W^(-),ZZ,and,Zγ,and investigate the corresponding signatures at the CEPC with the projected *** observe that the detectable parameter regions of these processes are *** combined analysis shows that the mass of dark matter m_(χ^(0)_(1))in these two models can be probed up to-150GeV and-450GeV,respectively,at a 95%confidence level.

关键词： CEPC dark matter loop correction

Chapter 3 Extra-galactic gamma-ray sources

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Chinese Physics C 2022年第3期46卷 63-84页

作者： Xiang-Yu Wang xiao-jun bi Zhen Cao Piero Vallania Han-Rong Wu Da-Hai Yan Qiang Yuan School of Astronomy and Space Sciences Nanjing UniversityNanjing 210093China Key Laboratory of Particle Astrophysics Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China INAF-Osservatorio Astrofisico di Torino Strada Osservatorio 2010025 Pino Torinese(TO)Italy and INFN Sezione di TorinoVia P.Giuria 110125 TorinoItaly Key Laboratory for the Structure and Evolution of Celestial Objects Yunnan ObservatoriesChinese Academy of SciencesKunming 650011China Key Laboratory of Dark Matter and Space Astronomy Purple Mountain ObservatoryChinese Academy of SciencesNanjing 210023China

Extra-galactic gammaray sources,such as gamma-ray bursts,active galactic nuclei,starburst galaxies,are interesting and important targets for LHAASO *** this chapter,the prospects of detecting these sources with LHAASO and their physical implications are *** upgrade plan for the Water Cherenkov Detector Array(WCDA),which aims to enhance the detectability of relatively lower energy photons,is also *** addition,a study on constraining the extragalactic background light with LHAASO observation of blazars is presented.

关键词： AGN Gamma-rays GRBs

Status of dark matter detection

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Frontiers of physics 2013年第6期8卷 794-827页

作者： xiao-jun bi Peng-Fei Yin Qiang Yuan Key Laboratory of Particle Astrophysics Institute of High Energy Physics Chinese Academy of Sciences Beijing 100049 China

The detection of dark matter has made great progresses in recent years. We give a brief review on the status and progress in dark matter detection, including the progresses in direct detection, collider detection at LHC and focus on the indirect detection. The results from PAMELA, ATIC, Fermi-LAT and relevant studies on these results are introduced. Then we give the progress on indirect detection of gamma rays from Fermi-LAT and ground based Cerenkov telescopes. Finally the detection of neutrinos and constraints on the nature of dark matter are reviewed briefly.

关键词： dark matter annihilation cosmic rays gamma rays