论文标题
选定后AGB候选人的K波段光谱
K-band spectra of selected post-AGB candidates
论文作者
论文摘要
我们提出了12个AGB候选后和相关恒星的中等分辨率（1000）K波段光谱。对于我们的样品中的几个对象，首次获得了这些光谱。在七个对象中检测到发射中的BR $γ$线，这些对象表示这些对象中的光电发发作。四个对象显示了我列的存在。我们在IRAS 06556+1623，IRAS 22023+5249，IRAS 18062+2410和IRAS 20462+3416的光谱中检测到H2发射线。 H2发射线比1-0 s（1）/2-1 s（1）表明，由于热后中央恒星的紫外线辐射，H2受到辐射激发。与其他研究者最近观察到的观察结果相比，某些对象的BR $γ$和H2排放通量有所不同。热后星IRA 22495+5134，IRAS 22023+5249，IRAS 18062+2410和IRAS 20462+3416似乎正在迅速发展到年轻的低激发行星星云阶段。本文中介绍的物体的光谱可能对将来的观察者有用，因为这些恒星中的一些显示频谱变化，并且由于这些恒星的AGB后演变相对较快。
We present medium resolution (1000) K-band spectra of 12 post-AGB candidates and related stars. For several objects in our sample, these spectra were obtained for the first time. The Br$γ$ line in emission is detected in seven objects indicating the onset of photo-ionization in these objects. Four objects show the presence of He i line. We detect H2 emission line in the spectra of IRAS 06556+1623, IRAS 22023+5249, IRAS 18062+2410 and IRAS 20462+3416. H2 emission line ratio 1-0 S(1)/2-1 S(1) indicate that H2 is radiatively excited due to the UV radiation of hot post-AGB central stars. When compared with the recent observations by other investigators, the Br$γ$ and H2 emission fluxes varied in some of the objects. The hot post-AGB stars IRAS 22495+5134, IRAS 22023+5249, IRAS 18062+2410 and IRAS 20462+3416 seem to be evolving rapidly to young low excitation planetary nebula phase. The spectra of the objects presented in this paper may be useful for future observers as some of these stars show spectral variation and since the post-AGB evolution of some of these stars is relatively rapid.
