论文标题
使用Pantheon+样本的高度红色类型的IA Supernovae限制R $ _V $变化
Constraining R$_V$ Variation Using Highly Reddened Type Ia Supernovae from the Pantheon+ Sample
论文作者
论文摘要
IA型超新星（SNE IA）是测量宇宙扩展历史的强大工具，但是Sne IA周围的灰尘的影响仍然未知，并且是一个关键的系统不确定性。改善我们对灰尘的经验描述的一种方法是分析高度红色的SNE IA（$ e（B-V）> 0.4 $，大致相当于拟合的Salt2 Light-Curve参数$ C> 0.3 $）。有了最近发布的万神殿+样品，由于仅具有高色（颜色高达$ c = 1.61 $），因此有57 sne IA被删除，这可以为您了解理解的巨大杠杆作用。先前的研究声称，$ r_v $随红色降低，尽管目前尚不清楚这是由于统计数据有限，选择效果或替代性解释所致。为了测试这一说法，我们适合两个单独的颜色劳斯力关系，一个用于主要的宇宙学样本（$ c <0.3 $），另一个用于高度红（$ c> 0.3 $）SNE IA。我们发现颜色亮度系数的变化与零一致。此外，我们将数据与具有不同颜色模型的仿真进行比较，并发现数据更喜欢平面依赖性$ r_v $的模型，而不是依赖性下降。最后，我们的结果在强烈支持ia sne ia的视线$ r_v $不是一个值，而是形成分布。
Type Ia supernovae (SNe Ia) are powerful tools for measuring the expansion history of the universe, but the impact of dust around SNe Ia remains unknown and is a critical systematic uncertainty. One way to improve our empirical description of dust is to analyse highly reddened SNe Ia ($E(B-V)>0.4$, roughly equivalent to the fitted SALT2 light-curve parameter $c>0.3$). With the recently released Pantheon+ sample, there are 57 SNe Ia that were removed because of their high colour alone (with colours up to $c=1.61$), which can provide enormous leverage on understanding line-of-sight $R_V$. Previous studies have claimed that $R_V$ decreases with redder colour, though it is unclear if this is due to limited statistics, selection effects, or an alternative explanation. To test this claim, we fit two separate colour-luminosity relationships, one for the main cosmological sample ($c<0.3$) and one for highly reddened ($c>0.3$) SNe Ia. We find the change in the colour-luminosity coefficient to be consistent with zero. Additionally, we compare the data to simulations with different colour models, and find that the data prefers a model with a flat dependence of $R_V$ on colour over a declining dependence. Finally, our results strongly support that line-of-sight $R_V$ to SNe Ia is not a single value, but forms a distribution.
