Asteroseismological constraints on the pulsating planetary nebula nucleus (PG 1159-type) RX J2117.1+3412
Asteroseismological constraints on the pulsating planetary nebula nucleus (PG 1159-type) RX J2117.1+3412
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DOI：
10.1051/0004-6361:20066452
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发表时间：
2006-10
影响因子：
6.5
通讯作者：
A. C'orsico;L. Althaus;M. M. Bertolami-M.;K. Werner
中科院分区：
文献类型：
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作者：
A. C'orsico;L. Althaus;M. M. Bertolami-M.;K. Werner
目标。我们提出了RXJ 2117.1 +3412，已知最热的脉动PG 1159星星的星震学推断。我们的研究结果是基于米勒Bertolami和Althaus（2006）最近提出的完整的PG 1159进化模型。方法.我们进行了广泛的计算的绝热g-模式脉动周期的PG 1159演化模型的恒星质量范围从0.530到0.741 M <$。PG 1159恒星模型是从ZAMS开始的祖星演化的完整过程中提取出来的，经过热脉冲AGB和再循环阶段到PG 1159恒星的域。通过比较观测到的周期间距与渐近周期间距以及计算周期间距的平均值，我们约束了RXJ2117.1+3412的恒星质量。我们还利用各个观测周期找到了RXJ2117.1+3412的代表性地震学模型。结果我们仅从周期间隔数据中得出恒星质量M = 0.56 0.57M <$。此外，我们还发现了一个代表RXJ2117.1+3412的最佳拟合模型，其有效温度Teff = 163400 K，恒星质量M = 0.565 M，表面重力log g = 6.61。得到的恒星光度和半径分别为log（L/L）= 3.36和log（R/R）= 1.23，富氦包层厚度为Menv = 0.02M。我们得到了地震距离d = 452 pc和行星状星云的线性尺寸DPN = 1.72 pc。这些推论似乎解决了RXJ2117.1+3412演化时间尺度和星云大小之间的差异。我们使用的所有地震学工具都得出结论，RXJ2117.1+3412必须有一个恒星质量M = 0.565 M，这与最近的星震学研究非常一致，但与光谱学加上演化轨迹的预测明显冲突。
Aims. We present asteroseismological inferences on RXJ2117.1+3412, the hottest known pulsating PG1159 star. Our results are based on full PG1159 evolutionary models recently presented by Miller Bertolami & Althaus (2006). Methods. We performed extensive computations of adiabatic g-mode pulsation periods on PG1159 evolutionary models with stellar masses ranging from 0.530 to 0.741M⊙. PG1159 stellar models are extracted from the complete evolution of progenitor stars started from the ZAMS, through the thermally pulsing AGB and born-again phases to the domain of the PG1159 stars. We constrained the stellar mass of RXJ2117.1+3412 by comparing the observed period spacing with the asymptotic period spacing and with the average of the computed period spacings. We also employed the individual observed periods to find a representative seismological model for RXJ2117.1+3412. Results. We derive a stellar mass M∗ � 0.56 0.57M⊙ from the period spacing data alone. In addition, we found a best-fit model representative for RXJ2117.1+3412 with an effective temperature Teff = 163400 K, a stellar mass M∗ = 0.565M⊙, and a surface gravity log g = 6.61. The derived stellar luminosity and radius are log(L∗/L⊙) = 3.36 and log(R∗/R⊙) = 1.23, respectively, and the He-rich envelope thickness is Menv = 0.02M⊙. We derive a seismic distance d � 452 pc and a linear size of the planetary nebula DPN � 1.72 pc. These inferences seem to solve the discrepancy between the RXJ2117.1+3412 evolutionary timescale and the size of the nebula. All of the seismological tools we use concur to the conclusion that RXJ2117.1+3412 must have a stellar mass M∗ � 0.565M⊙, much in agreement with recent asteroseismology studies and in clear conflict with the predictions of spectroscopy plus evolutionary tracks.