搜索结果: 1-15 共查到“理学 Pion”相关记录67条 . 查询时间(0.093 秒)
PHOTON-PHOTON SCATTERING, PION POLARIZABILITY, AND CHIRAL-SYMMETRY
Meson polarizability dispersion relations chiral perturbation theory expert at low amplitude decentralized processing
2014/12/23
Recent attempts to detect the pion polarizability via analysis of γγ→ππ measurements are examined. The connection between calculations based on dispersion relations and on chiral perturbation theory i...
Asymptotic limits and the structure of the pion form factor
Dispersion technology solve meson chiral perturbation theory high energy low energy limit
2014/12/22
We use dispersive techniques to address the behavior of the pion form factor as Q2 → ∞ and Q2 → 0. We perform the matching with the constraints of perturbative QCD and chiral perturbation theory in th...
Subleading corrections to parity-violating pion photoproduction
Light photons meson photovoltaic coupling
2014/12/22
We compute the photon asymmetry Bγ for near threshold parity-violating (PV) pion photoproduction through subleading order. We show that subleading contributions involve a new combination of PV couplin...
近代物理所理论物理室的科研人员，研究pion介子阈下产生的介质效应获得一些新结论。
重离子核反应粒子产生的介质效应大小不能由实验直接确定，只能通过微观理论计算得出或者输运计算与实验数据比较间接得出，然而这样得出的结论依赖于研究的模型。近代物理所的研究表明，低能核反应pion介子产生的荷电pion介子比值的介质效应非常明显（见图1），而目前介质效应的大小还不确定，这给人们通过研究低能核反应pio...
中国科学院近代物理研究所核理论组科研人员新近系统研究了S波底介子的隐底双pion衰变过程，提出了5S的隐底双Pion衰变过程的衰变机制，取得了系列成果。研究发现，在这些衰变过程中，除了直接衰变过程的贡献外，还有末态相互作用的贡献以及首次提出的初态单Pion出射机制。利用这三种机制的干涉效应，能够很好地解释实验测到的双Pion不变质量谱的分布和角分布。
Asymptotic behavior of pion form factors
Vector Meson Dominance Regge behavior dispersion relations
2011/7/21
We consider the electromagnetic and transition pion form factors. Using dispersion relations we simultaneously describe both the hadronic, time-like region and the asymptotic region of large energy-mo...
Deciphering non-femtoscopic two-pion correlations in $p+p$ collisions with simple analytical models
non-femtoscopic two-pion analytical models
2011/7/21
A simple model of non-femtoscopic particle correlations in proton-proton collisions is proposed.
$Z_b(10610)$ and $Z_b(10650)$ structures produced by the initial single pion emission in the $Υ(5S)$ decays
$Z_b(10610)$ $Z_b(10650)$ initial single pion emission
2011/7/21
We propose an unique mechanism called {\it Initial Single Pion Emission} existing in the $\Upsilon(5S)$ decays, and further study the line shapes of $d\Gamma(\Upsilon(5S\to \Upsilon(nS)\pi^+\pi^-))/dm...
Single Spin Asymmetries in Charged Pion Production from Semi-Inclusive Deep Inelastic Scattering on a Transversely Polarized $^3$He Target
Transversely Polarized $^3$He Target Charged Pion Production
2011/7/21
We report the first measurement of target single spin asymmetries in the semi-inclusive $^3{He}(e,e'\pi^\pm)X$ reaction on a transversely polarized target. The experiment, conducted at Jefferson Lab u...
Pion productions by proton and Helium-3 on Au197 target at beam energies of 2.8, 5, 10 and 16.587 GeV/nucleon
GeV/nucleon
2011/7/20
Based on a Relativistic Boltzmann-Uehling- Uhlenbeck transport model, proton and $^{3}$He induced reactions on $^{197}$Au target at beam energies of 2.8, 5, 10 and 16.587 GeV/nucleon are studied.
Pions may remain stable under certain conditions in a dense media at zero temperature in the normal phase (non pion superfluid state). The stability condition is achieved when the in-media pion width ...
（反）核子-核子碰撞过程中的双pion介子产生理论研究新进展（图）
（反）核子-核子碰撞 双pion介子 产生理论 新进展
2011/10/19
中国科学院近代物理研究所理论组研究人员利用有效拉氏量模型，系统地分析了核子-核子碰撞过程中的双pion介子的产生过程。该模型包含了所有粒子物理数据表上质量在1.72GeV下的共振态，并包括pion，rhon和eta等介子的交换。计算结果表明，N*(1440)和Delta(1232)在阈值附近贡献很大，而Delta(1600)和Delta(1620)在入射动能1.5GeV以上贡献较大，从而使得该模型...
We consider the electromagnetic and transition pion form factors. Using dispersion relations we simultaneously describe both the hadronic, time-like region and the asymptotic region of large energy-mo...
Deciphering non-femtoscopic two-pion correlations in $p+p$ collisions with simple analytical models
non-femtoscopic two-pion correlations simple analytical models
2011/7/21
A simple model of non-femtoscopic particle correlations in proton-proton collisions is proposed. The model takes into account correlations induced by the conservation laws as well as correlations indu...
Effect of three-pion unitarity on resonance poles from heavy meson decays
three-pion unitarity poles heavy meson decays
2011/4/7
Effect of three-pion unitarity on resonance poles from heavy meson decays 。