论文标题
DAV Star L19-2的Asterosemology
Asteroseismology of the DAV star L19-2
论文作者
论文摘要
L19-2是DAV恒星，从1976年到2013年，已间歇性地观察到。五种独立的脉动模式为350 \，S，192 \，S，143 \，S，S，118 \，S和113 \，S。这五个模式可用于约束拟合模型。可以通过O-C方法获得192 \，S和113 \，S的O-C方法，可用于研究DAV恒星的演化效应。使用\ texttt {wdec}（2018版），进化了大型示例DAV型星模型。计算理论模式并用于拟合观察到的模式。经过精细的模型配件后，我们获得了一个绝对差为$ = $ = 0.06 \，s的最佳模型。通过参数化核心氧轮廓，\ texttt {wdec}（2018版）过程可以大大减少Asterosemology模型的拟合误差。根据我们的最佳模型，通过模型发光度获得的距离与Gaia Data Release 2报告的距离仅为1 \％。L19-2是一个庞大而热的DAV星，具有相对较厚的H大气和较厚的HE层。我们最佳模型的恒星参数和周期变化率对先前工作的修改有所修改。我们的最佳模型具有较大的中央氧丰度。中央氧丰度与先前的恒星进化的物理过程密切相关。许多关于白矮人的星星学工作都有机会探索祖细胞星。
L19-2 is a DAV star, which has been intermittently observed from 1976 to 2013. Five independent pulsation modes of 350\,s, 192\,s, 143\,s, 118\,s, and 113\,s are identified. The five modes can be used to constrain the fitting models. The rates of period change can be obtained through the O-C method for modes of 192\,s and 113\,s, which can be used to study the evolution effect of DAV stars. Using the \texttt{WDEC} (2018 version), a large sample DAV star models are evolved. The theoretical modes are calculated and used to fit the observed modes. After fine model fittings, we obtain an optimal model with an absolute difference of $Φ$ = 0.06\,s. By parameterizing the core oxygen profile, the \texttt{WDEC} (2018 version) procedure can greatly reduce the fitting error of asteroseismological model. According to our optimal model, the distance obtained through the model luminosity is only 1\% different from that reported by the Gaia Data Release 2. The L19-2 is a massive and hot DAV star with relatively a thick H atmosphere and a thick He layer. The stellar parameters and the rates of period change of our optimal model are a little modifications to that of the previous work. Our optimal model has a large central oxygen abundance. The central oxygen abundance is strongly correlated with the previous physical process of stellar evolution. A lot of asteroseismological work on white dwarfs have an opportunity to explore the progenitor stars.
