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Holographic technicolor model and dark matter

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Chinese Physics C 2020年第9期44卷 16-24页

作者： Yidian Chen xiao-jun bi Mei Huang Institute of High Energy Physics Chinese Academy of SciencesBeijing 100049China School of Physics University of Chinese Academy of SciencesBeijing 100049China School of Nuclear Science and Technology University of Chinese Academy of SciencesBeijing 100049China

We investigate the strongly coupled minimal walking technicolor model(MWT)in the framework of a bottom-up holographic model,where the global SU(4)symmetry breaks into SO(4)*** the holographic model,we found that 125 GeV composite Higgs particles and small Peskin–Takeuchi S parameter can be achieved *** addition,the model predicts a large number of particles at the TeV scale,including dark matter candidates Technicolor Interacting Massive Particles(TIMPs).If we consider the dark matter nuclear spin-independent cross-section in the range of 10^−45∼10^−48cm^2,which can be detected by future experiments,the mass range of TIMPs predicted by the holographic technicolor model is 2∼4 TeV.

关键词： dark matter holography technicolor

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

Potential for Constraining Propagation Parameters of Galactic Cosmic Rays with the High Energy Cosmic-radiation Detection Facility on Board China's Space Station

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Research in Astronomy and Astrophysics 2023年第8期23卷 290-296页

作者： Zhi-Hui Xu Qiang Yuan Zhi-Cheng Tang xiao-jun bi Key Laboratory of Dark Matter and Space Astronomy Purple Mountain ObservatoryChinese Academy of SciencesNanjing 210023China School of Astronomy and Space Science University of Science and Technology of ChinaHefei 230026China Key Laboratory of Particle Astrophysics Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China University of Chinese Academy of Sciences Beijing 100049China

Precise measurements of the spectra of secondary and primary cosmic rays are crucial for understanding the origin and propagation of those energetic *** High Energy Cosmic-radiation Detection(HERD)facility on board China's Space Station,which is expected to operate in 2027,will push the direct and precise measurements of cosmic-ray fluxes up to PeV *** this work,we investigate the potential of HERD for studying the propagation of cosmic rays using measurements of boron,carbon,and oxygen *** find that,compared with the current results,the new HERD measurements can improve the accuracy of the propagation parameters by 8%–40%.The constraints on the injection spectra at high energies will also be improved.

关键词： (ISM:)cosmic rays-instrumentation detectors-The Galaxy

A new perspective on the diffuse gamma-ray emission excess

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Chinese Physics C 2024年第11期48卷 162-169页

作者： En-Sheng Chen Kun Fang xiao-jun bi Key Laboratory of Particle Astrophysics Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China University of Chinese Academy of Sciences Beijing 100049China

The Large High-Altitude Air Shower Observatory(LHAASO)recently published measurements of diffuse Galactic gamma-ray emission(DGE)in the 10−1000 TeV energy *** measured DGE flux is significantly higher than the expectation from hadronic interactions between cosmic rays(CRs)and the interstellar *** excess has been proposed to originate from unknown extended sources produced by electron radiation,such as pulsar wind nebulae or pulsar halos(PWNe/halos).In this paper,we propose a new perspective to explain the DGE excess observed by *** masking regions used in the LHAASO DGE measurement may not fully encompass the extended signals of PWNe/*** employing a two-zone diffusion model for electrons around pulsars,we find that the DGE excess in most regions of the Galactic plane can be well explained by the signal leakage model under certain *** results indicate that this signal leakage from known sources and contributions from unresolved sources should be considered as complementary in explaining the DGE excess.

关键词： cosmic rays diffuse gamma-ray emission pulsar wind nebulae pulasr halos two-zone diffusion

Klein–Nishina Effect and the Cosmic Ray Electron Spectrum

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Chinese Physics Letters 2021年第3期38卷 127-131页

作者： Kun Fang xiao-jun bi Su-Jie Lin Qiang Yuan Key Laboratory of Particle Astrophysics Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China University of Chinese Academy of Sciences Beijing 100049China School of Physics and Astronomy Sun Yat-Sen UniversityZhuhai 519082China Key Laboratory of Dark Matter and Space Astronomy Purple Mountain ObservatoryChinese Academy of SciencesNanjing 210023China School of Astronomy and Space Science University of Science and Technology of ChinaHefei 230026China Center for High Energy Physics Peking UniversityBeijing 100871China

Radiative energy losses are very important in regulating the cosmic ray electron and/or positron(CRE) spectrum during their propagation in the Milky Way. Particularly, the Klein–Nishina(KN) effect of the inverse Compton scattering(ICS) results in less efficient energy losses of high-energy electrons, which is expected to leave imprints on the propagated electron spectrum. It has been proposed that the hardening of CRE spectra around 50 GeV observed by Fermi-LAT, AMS-02, and DAMPE could be due to the KN effect. We show in this work that the transition from the Thomson regime to the KN regime of the ICS is actually quite smooth compared with the approximate treatment adopted in some previous works. As a result, the observed spectral hardening of CREs cannot be explained by the KN effect. It means that an additional hardening of the primary electrons spectrum is needed. We also provide a parameterized form for the accurate calculation of the ICS energy-loss rate in a wide energy range.

关键词： effect. regime Electron

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

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Nearby source interpretation of differences among light and medium composition spectra in cosmic rays

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Frontiers of physics 2021年第2期16卷 195-200页

作者： Qiang Yuan bing-Qiang Qiao Yi-Qing Guo Yi-Zhong Fan xiao-jun bi Key Laboratory of Dark Matter and Space Astronomy Purple Mountain ObservatoryChinese Academy of SciencesNanjing 210023China School of Astronomy and Space Science University of Science and Technology of ChinaHefei 230026China Center for High Energy Physics Peking UniversityBeijing 100871China Key Laboratory of Particle Astrophysics Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China University of Chinese Academy of Sciences Beijing 100049China

Recently the AMS-02 reported the precise measurements of the energy spectra of medium-mass compositions(Neon,Magnesium,Silicon)of primary cosmic rays,which reveal different properties from those of light compositions(Helium,Carbon,Oxygen).Here we propose a nearby source scenario,together with the background source contribution,to explain the newly measured spectra of cosmic ray Ne,Mg,Si,and particularly their differences from that of He,C,*** differences at high energies can be naturally accounted for by the element abundance of the nearby ***,the abundance ratio of the nearby source to the background of the Ne,Mg,Si elements is lower by a factor of~1.7 than that of the He,C,O *** a diference could be due to the abundance difference of the stellar evolution of the progenitor star or the acceleration process/environment,of the nearby *** scenario can simultaneously explain the high-energy spectral softening features of cos-mic ray spectra revealed recently by CREAM/NUCLEON/DAMPE,as well as the energy-dependent behaviors of the large scale *** is predicted that the dipole anisotropy amplitudes below PeV energies of the Ne,Mg,Si group are smaller than that of the He,C,O group,which can be tested with future measurements.

关键词： cosmic rays spectra and anisotropies

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

Implications of axion-like particles from the Fermi-LAT and *** of PG 1553+113 and PKS 2155−304

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Chinese Physics C 2021年第2期45卷 578-587页

作者： jun-Guang Guo Hai-jun Li xiao-jun bi Su-Jie Lin Peng-Fei Yin Key Laboratory of Particle Astrophysics Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China School of Physics University of Chinese Academy of SciencesBeijing 100049China

We investigate the axion-like particle(ALP)-photon oscillation effect in the high-energy y-ray spectra of PG 1553+113 and PK.S 2155-304 measured by Fermi-LAT and *** choice of extragalactic background light(EBL)model,which induces the attenuation effect in observed y-ray spectra,affects the ALP *** the ordinary EBL model that prefers a null hypothesis,we set constraints on the ALP-photon coupling constant at 95% *** gay 5×10^(-11) GeV^(-1) for the ALP mass 〜10 *** also consider the CIBER observation of the cosmic infrared radiation,which shows an excess at wavelengths of -1μm after the substraction of ***-energy gamma-rays from extragalactic sources at high redshifts would suffer from a more significant attenuation effect caused by this *** this case,we find that the ALP-photon oscillation would improve the fit to the observed spectra of PKS 2155-304 and PG 1553+113 and find a favored parameter region at 95%CL..

关键词： axion-like particle gamma-ray extragalactic background light