论文标题
顺序bremsstrahlung中的LPM效果：$ 1/n_c^2 $更正
The LPM Effect in sequential bremsstrahlung: $1/N_c^2$ corrections
论文作者
论文摘要
关于在夸克 - 胶子等离子体或其他QCD介质中的中等内部高能参与者阵雨的一个重要问题是，在给定淋浴中的parton的连续分裂是否可以视为机械独立的量子，或者是否连续两个连续的分布的地层时间都具有显着重叠。重叠形成时间效果的各种以前的计算都具有（i）限制对柔软的bremsstrahlung限制的关注，否则（ii）使用了大$ n_c $限制（其中$ n_c {=} 3 $是夸克颜色的数量）。在本文中，我们首先研究了由重叠效应的计算所使用的大$ n_c $限制的准确性，这些效应避免了柔软的bremsstrahlung近似。具体来说，我们计算$ 1/n_c^2 $校正到先前的$ n_c {=} \ infty $ resust $ gg \ gg \ to gg \ to ggg \ to ggg $ to ggg $的两个连续的Gluon分组$ g \ to gg $。以$ 1/n_c^2 $的订单，在编队时间的重叠期间必须考虑有趣且非平凡的颜色动力学。
An important question concerning in-medium high-energy parton showers in a quark-gluon plasma or other QCD medium is whether consecutive splittings of the partons in a given shower can be treated as quantum mechanically independent, or whether the formation times for two consecutive splittings instead have significant overlap. Various previous calculations of the effect of overlapping formation times have either (i) restricted attention to a soft bremsstrahlung limit, or else (ii) used the large-$N_c$ limit (where $N_c{=}3$ is the number of quark colors). In this paper, we make a first study of the accuracy of the large-$N_c$ limit used by those calculations of overlap effects that avoid a soft bremsstrahlung approximation. Specifically, we calculate the $1/N_c^2$ correction to previous $N_c{=}\infty$ results for overlap $g \to gg \to ggg$ of two consecutive gluon splittings $g \to gg$. At order $1/N_c^2$, there is interesting and non-trivial color dynamics that must be accounted for during the overlap of the formation times.
