On the chiral imbalance and Weibel instabilities

详细信息    查看全文

• 作者：Avdhesh Kumar^a ; ^{avdhesh@prl.res.in" class="auth_mail" title="E-mail the corresponding author} ; Jitesh R. Bhatt^a ; ^{jeet@prl.res.in" class="auth_mail" title="E-mail the corresponding author} ; P.K. Kaw^b ; ^{kaw@ipr.res.in" class="auth_mail" title="E-mail the corresponding author}
• 关键词：Chiral imbalance ; Berry curvature ; Momentum anisotropy
• 刊名：Physics Letters B
• 出版年：2016
• 出版时间：10 June 2016
• 年：2016
• 卷：757
• 期：Complete
• 页码：317-323
• 全文大小：711 K

文摘

We study the chiral-imbalance and the Weibel instabilities in presence of the quantum anomaly using the Berry-curvature modified kinetic equation. We argue that in many realistic situations, e.g. relativistic heavy-ion collisions, both the instabilities can occur simultaneously. The Weibel instability depends on the momentum anisotropy parameter ξ   and the angle (θ_n${\theta }_n$) between the propagation vector and the anisotropy direction. It has maximum growth rate at θ_n=0${\theta }_n=0$ while θ_n=π/2${\theta }_n=\pi /2$ corresponds to a damping. On the other hand the pure chiral-imbalance instability occurs in an isotropic plasma and depends on difference between the chiral chemical potentials of right and left-handed particles. It is shown that when θ_n=0${\theta }_n=0$, only for a very small values of the anisotropic parameter ξ∼ξ_c$\xi \sim {\xi }_c$, growth rates of the both instabilities are comparable. For the cases ξ_c<ξ≪1${\xi }_c<\xi \ll 1$ or ξ≳1$\xi \gtrsim 1$ at θ_n=0${\theta }_n=0$, the Weibel modes dominate over the chiral-imbalance instability if μ₅/T≤1${\mu }_5/T\le 1$. However, when μ₅/T≥1${\mu }_5/T\ge 1$, it is possible to have dominance of the chiral-imbalance modes at certain values of θ_n${\theta }_n$ for an arbitrary ξ.