论文标题
在轴轴耦合上推进球状聚类约束
Advancing Globular Cluster Constraints on the Axion-Photon Coupling
论文作者
论文摘要
我们使用$ r_2 $参数（渐变的参数）来改善从恒星进化得出的轴 - 光子耦合上的当前上限，渐近巨型分支上的恒星种群与球状簇中的水平分支的比率。我们将其与使用恒星进化代码台面的模拟数据进行比较，其中包括轴突产生的影响。特别注意详细量化不确定性对$ r $和$ r_2 $参数的影响，原因是对流核心边界的建模。使用半传染的混合方案，我们将轴 - 光子耦合限制为$ g_ {aγγ} <0.47 \ times 10^{ - 10}〜\ mathrm {gev}^{ - 1} $。这排除了QCD轴和类似轴的粒子参数空间的新区域。来自Atterosemology的补充证据表明，这可能会提高到$ G_ {Aγγ} <0.34 \ times 10^{ - 10}〜\ Mathrm {Gev}^{ - 1} $，作为围绕在交流边界混合的不确定性的不确定性。
We improve the current upper bound on the axion-photon coupling derived from stellar evolution using the $R_2$ parameter, the ratio of stellar populations on the Asymptotic Giant Branch to Horizontal Branch in Globular Clusters. We compare this with data from simulations using the stellar evolution code MESA which include the effects of axion production. Particular attention is given to quantifying in detail the effects of uncertainties on the $R$ and $R_2$ parameters due to the modelling of convective core boundaries. Using a semiconvective mixing scheme we constrain the axion-photon coupling to be $g_{aγγ} < 0.47 \times 10^{-10}~\mathrm{GeV}^{-1}$. This rules out new regions of QCD axion and axion-like particle parameter space. Complementary evidence from asteroseismology suggests that this could improve to as much as $g_{aγγ} < 0.34 \times 10^{-10}~\mathrm{GeV}^{-1}$ as the uncertainties surrounding mixing across convective boundaries are better understood.
