Three Wide-Separation L Dwarf Companions from the Two Micron All Sky Survey: Gliese 337C, Gliese 618.1B, and HD 89744B
Three Wide-Separation L Dwarf Companions from the Two Micron All Sky Survey: Gliese 337C, Gliese 618.1B, and HD 89744B
复制标题
来自两微米全天巡天的三个宽间隔 L 型矮星伴星：Gliese 337C、Gliese 618.1B 和 HD 89744B
DOI：
--
复制
发表时间：
2001
期刊：
影响因子：
--
通讯作者：
U. F. Station
中科院分区：
文献类型：
--
作者：
J. Wilson;J. Kirkpatrick;J. Gizis;M. Skrutskie;D. Monet;J. R. H. Cornell;Ipac;Umass;U. F. Station
我们提出了两个确认的宽分离L矮共同自行同伴附近的恒星和一个候选人确定从两微米全天巡天。光谱学的光谱类型有L0 V、L2.5 V和L 8 V，提供了伴星的近红外低分辨率光谱，以及一个跨越M6 V-T矮星的已知天体网格，以支持这些和未来的L矮星在z′JHK波段的光谱类型分配。使用已发表的测量，我们估计年龄的同伴从物理性质的小学。这些粗略的年龄使我们能够利用理论上的低质量星星和褐矮星演化模型来估计伴星的质量。本文中新发现的L型矮星使已知的宽双星（Δ ≥ 100 Au）L型矮星伴星的数量增加到9个。其中一颗L型矮星是F7 IV-V+系外行星系统HD 89744 Ab的宽间隔伴星。
We present two confirmed wide-separation L dwarf common proper-motion companions to nearby stars and one candidate identified from the Two Micron All Sky Survey. Spectral types from optical spectroscopy are L0 V, L2.5 V, and L8 V. Near-infrared, low-resolution spectra of the companions are provided, as well as a grid of known objects spanning M6 V–T dwarfs to support spectral type assignment for these and future L dwarfs in the z′JHK bands. Using published measurements, we estimate ages of the companions from physical properties of the primaries. These crude ages allow us to estimate companion masses using theoretical low-mass star and brown dwarf evolutionary models. The new L dwarfs in this paper bring the number of known wide-binary (Δ ≥ 100 AU) L dwarf companions of nearby stars to nine. One of the L dwarfs is a wide-separation companion to the F7 IV–V+extrasolar planet system HD 89744Ab.