标题： B → X_s gamma 在超对称中：超越领先阶的大贡献 显示英文标题

标题： B -> X_s gamma in supersymmetry: large contributions beyond the leading order

摘要： 我们讨论在超对称模型中，B → X_s gamma可能产生的大贡献，这些贡献出现在次领头阶。 它们可能来源于被tan(beta)因子增强的项，当两个希格斯真空期望值的比值较大时，或者来源于M_{超对称}/M_W的对数，当超对称粒子明显比W玻色子重时。 我们给出了包含所有潜在大高阶贡献的简洁公式。 我们发现，在次领头阶的tan(beta)项不仅来自于Hall-Rattazzi-Sarid效应（底夸克质量与Yukawa耦合之间的修正关系），还来自于顶夸克Yukawa耦合中的类似效应。 最后，我们展示了在大tan(beta)区域，次领头阶修正可以显著降低带电Higgs粒子质量的限制，即使超对称粒子非常重。 显示英文摘要

摘要： We discuss possible large contributions to B -> X_s gamma, which can occur at the next-to-leading order in supersymmetric models. They can originate from terms enhanced by tan(beta) factors, when the ratio between the two Higgs vacuum expectation values is large, or by logarithm of M_{susy}/M_W, when the supersymmetric particles are considerably heavier than the W boson. We give compact formulae which include all potentially large higher-order contributions. We find that tan(beta) terms at the next-to-leading order do not only appear from the Hall-Rattazzi-Sarid effect (the modified relation between the bottom mass and Yukawa coupling), but also from an analogous effect in the top-quark Yukawa coupling. Finally, we show how next-to-leading order corrections, in the large tan(beta) region, can significantly reduce the limit on the charged-Higgs mass, even if supersymmetric particles are very heavy.