The discovery of a debris disc around the DAV white dwarf PG 1541+651
The discovery of a debris disc around the DAV white dwarf PG 1541+651
复制标题
在 DAV 白矮星 PG 1541 651 周围发现碎片盘
DOI：
--
复制
发表时间：
2011
期刊：
影响因子：
--
通讯作者：
P. Dufour
中科院分区：
文献类型：
--
作者：
M. Kilic;A. Patterson;S. Barber;S. Leggett;P. Dufour
为了寻找演化恒星周围的拱星盘，我们用彼得斯自动红外成像望远镜（PAIRITEL）从帕洛玛绿色巡天中锁定了大约100颗DA白色矮星。在这里，我们报告发现了一个碎片盘周围的这些目标之一，脉动的白色矮星PG 1541+651（KX天龙，以下简称PG 1541）。我们在K波段探测到PG 1541附近有一个显著的通量过剩。在美国航天局红外望远镜设施获得的后续近红外分光观测和用温暖的斯皮策空间望远镜进行的光度观测证实，在0.13-0.36 R（11-32倍恒星半径）范围内存在一个倾角为60°的温暖碎片盘。在Teff= 11 880 K时，PG 1541几乎是DAV白色矮星G29-38的孪生兄弟，G29-38也拥有碎片盘。所有先前已知的尘埃白色矮星都是DAZ/DBZ光谱类型，这是由于圆盘中的金属吸积。高分辨率的光学光谱学是必要的，以寻找金属吸收线在PG 1541和限制吸积率从光盘。PG 1541距离太阳只有55 pc，在我们的调查中发现了它的圆盘，这表明我们对附近尘埃白色矮星的了解还远远不够。
To search for circumstellar discs around evolved stars, we targeted roughly 100 DA white dwarfs from the Palomar Green survey with the Peters Automated Infrared Imaging Telescope (PAIRITEL). Here we report the discovery of a debris disc around one of these targets, the pulsating white dwarf PG 1541+651 (KX Draconis, hereafter PG1541). We detect a significant flux excess around PG1541 in the K band. Follow-up near-infrared spectroscopic observations obtained at the NASA Infrared Telescope Facility and photometric observations with the warm Spitzer Space Telescope confirm the presence of a warm debris disc within 0.13–0.36 R⊙ (11–32 × the stellar radius) at an inclination angle of 60°. At Teff= 11 880 K, PG1541 is almost a twin of the DAV white dwarf G29-38, which also hosts a debris disc. All previously known dusty white dwarfs are of the DAZ/DBZ spectral type due to accretion of metals from the disc. High-resolution optical spectroscopy is needed to search for metal absorption lines in PG1541 and to constrain the accretion rate from the disc. PG1541 is only 55 pc away from the Sun and the discovery of its disc in our survey demonstrates that our knowledge of the nearby dusty white dwarf population is far from complete.