论文标题
成核不是关键 - 对NMSSM中的electroweak相变的案例研究
Nucleation is More than Critical -- A Case Study of the Electroweak Phase Transition in the NMSSM
论文作者
论文摘要
电动eakeakbaryogeny是一种有吸引力的机制，可以通过强大的一阶电子相变产生宇宙的重子不对称。我们比较了临界温度下真空结构所暗示的相变模式，其中局部最小值是退化的，从计算通过隧道通过横向分离局部最小值的屏障来计算成核的概率。启发式上，如果局部最小值之间的障碍太高，或者最小值之间的距离（在田间空间中）太大，则成核变得困难。作为表现出这种行为的模型的一个示例，我们研究了近乎最小的超对称标准模型，该模型的标量扇区包含两个SU（2）Doublets和一个量规单程。我们发现，与仅基于临界温度的计算相比，成核概率的计算对于强一级电子相变的参数空间的不同区域更喜欢参数空间的不同区域。我们的结果表明，仅通过临界温度分析真空结构可以提供相变模式的误导性图片，进而出目的参数空间适合于电子eak baryogenogeny。
Electroweak baryogenesis is an attractive mechanism to generate the baryon asymmetry of the Universe via a strong first order electroweak phase transition. We compare the phase transition patterns suggested by the vacuum structure at the critical temperatures, at which local minima are degenerate, with those obtained from computing the probability for nucleation via tunneling through the barrier separating local minima. Heuristically, nucleation becomes difficult if the barrier between the local minima is too high, or if the distance (in field space) between the minima is too large. As an example of a model exhibiting such behavior, we study the Next-to-Minimal Supersymmetric Standard Model, whose scalar sector contains two SU(2) doublets and one gauge singlet. We find that the calculation of the nucleation probabilities prefers different regions of parameter space for a strong first order electroweak phase transition than the calculation based solely on the critical temperatures. Our results demonstrate that analyzing only the vacuum structure via the critical temperatures can provide a misleading picture of the phase transition patterns, and, in turn, of the parameter space suitable for electroweak baryogenesis.
