论文标题
重新检查Hetdex Pilot调查中观察到的局部星形星系的贝叶斯颜色过剩估计
Re-examining the Bayesian colour excess estimation for the local star-forming galaxies observed in the HETDEX Pilot Survey
论文作者
论文摘要
在我以前对局部恒星形成星系的重新分析中，在爱好 - 昏迷的望远镜暗能量实验（HETDEX）试点调查中观察到，我报道了E（b-v）的高估，从而破坏了原始研究中新星系研究的主张。在此，我重新检查是否可以通过采用科学动机的新先验来缓解E（B -V）高估问题。我使用强线方法和四个模型参数 - 金属度12 + log（O/h），星云发射线颜色过剩E（B-V），内在[O III] $ 5007 $ 5007线路通量和内在[N II] $ 6584 Line Line Line Flux模拟了星系的发射线通量和四个模型参数 - 金属度（O/H），Nebula发射线颜色过剩E（B-V）。 Based on mock-data tests, I found that all input values can be recovered within and around the 1-$σ$ credible interval by adopting suitable priors for the intrinsic [O III] $λ$5007 and [N II] $λ$6584 line fluxes: the inverse gamma distribution reflecting the logical constraint that an intrinsic emission-line flux must exceed the observed (reddened) emission-line flux.对两个金属校准进行了模拟数据测试，三个颜色过量输入值[E（b -v）= 0.1、0.3和0.5]和两个金属输入值[12 + log（o/h）= 8.0和8.5]。我还发现，新的先验可以减少SFR高估八倍。这项研究表明，当可能性无法正确限制模型参数时，贝叶斯参数估计如何实现更准确的估计，而无需进一步观察。
In my previous reanalysis of the local star-forming galaxies observed in the Hobby-Eberly Telescope Dark Energy Experiment (HETDEX) pilot survey, I reported that the overestimation of E(B - V), hence the star formation rate (SFR), undermined the claim of new galaxy population discovery in the original study. Herein, I re-examine whether the E(B - V) overestimation problem can be alleviated in the Bayesian parameter estimation framework by adopting scientifically motivated new priors. I modelled the emission-line fluxes of galaxies using the strong-line method and four model parameters-metallicity 12 + log (O/H), nebula emission-line colour excess E(B - V), intrinsic [O III] $λ$5007 line flux and intrinsic [N II] $λ$6584 line flux. Based on mock-data tests, I found that all input values can be recovered within and around the 1-$σ$ credible interval by adopting suitable priors for the intrinsic [O III] $λ$5007 and [N II] $λ$6584 line fluxes: the inverse gamma distribution reflecting the logical constraint that an intrinsic emission-line flux must exceed the observed (reddened) emission-line flux. The mock-data tests were performed for two metallicity calibrations, three colour excess input values [E(B - V) = 0.1, 0.3 and 0.5] and two metallicity input values [12 + log (O/H) = 8.0 and 8.5]. I also found that the new prior can diminish the SFR overestimation eightfold. This study demonstrates how the Bayesian parameter estimation can achieve more accurate estimates with no further observations when the likelihood does not constrain the model parameters correctly.
