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单词 pair production
释义

pair production

英汉-汉英词典
电子偶的产生
词组 | 习惯用语
您要查找的是不是:
    electron-positron pair production 电子;正电子对产生
    hyperon pair production 超子对产生
    electron-position pair production 正负电子对形成
    pair production coefficient 对产生系数
    magnetic pair production 磁对产生
    pair production effect 电子对效应
    quark pair production 夸克对产生
    internal pair production 内对产生;内部电子对形成;内电子对产生
    electron pair production 电子对生成;电子对产生;电子对形成
pair production [物][电子] 电子偶的产生
production of pairs 正负电子对产生
中文百科

成对产生

在原子核物理学中,成对产生(pair production)指的是基本粒子和其反粒子的创生,例如,电子和其反粒子正子,缈子与反缈子,陶子与反陶子。通常当一个光子或另外一个中性玻色子,与原子核或另外一个中性玻色子或甚至自己本生相互作用时,会发生成对产生。在原子核里,一个高能量光子会因成对产生而形成电子和正子对偶。这过程必须遵守能量守恒定律和动量守恒定律。生成的粒子的所有其它守恒量(例如角动量、电荷量、轻子数)都必须总和为零。根据质能转换公式,光子的能量必需等于两个电子的质量,其中一半转换成电子,另一半则转换成正子。当然,只要光子的能量符合的话,形成其它质量更大的也可以(像是缈子、陶子等)。

英语百科

Pair production 成对产生

Feynman Diagram of electron-positron pair production. One can calculate multiple diagrams to get the cross section
DESY-Blasenkammeraufnahme; eine Paarbildung ist farbig markiert. Die grüne Bahn des Photons ist nicht direkt beobachtet, sondern aus den spiralförmigen Bahnen der Ladungen rekonstruiert.

Pair production is the creation of an elementary particle and its antiparticle, for example creating an electron and positron, a muon and antimuon, or a proton and antiproton. Pair production often refers specifically to a photon creating an electron-positron pair near a nucleus but can more generally refer to any neutral boson creating a particle-antiparticle pair. In order for pair production to occur, the incoming energy of the interaction must be above a threshold in order to create the pair  at least the total rest mass energy of the two particles  and that the situation allows both energy and momentum to be conserved. However, all other conserved quantum numbers (angular momentum, electric charge, lepton number) of the produced particles must sum to zero  thus the created particles shall have opposite values of each other. For instance, if one particle has electric charge of +1 the other must have electric charge of 1, or if one particle has strangeness of +1 then another one must have strangeness of 1. The probability of pair production in photon-matter interactions increases with photon energy and also increases approximately as the square of atomic number of the nearby atom.

近义、反义、联想词
近义词
n.
natural process, natural action, action, activity

英英词典
pair production n.
  1. the transformation of a gamma-ray photon into an electron and a positron when the photon passes close to an atomic nucleus

  2. synonymous: pair creation, pair formation
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