论文标题
NGC 7027中原子和原子离子的红外线排放：改进红外金属线的波长确定，并可能检测Zn $^{5+} $
Infrared line emissions from atoms and atomic ions in NGC 7027: improved wavelength determinations for infrared metal lines and a probable detection of Zn$^{5+}$
论文作者
论文摘要
An infrared L- and M-band spectral survey, performed toward the young planetary nebula NGC 7027 with the iSHELL instrument on NASA's Infrared Telescope Facility (IRTF), has revealed more than 20 vibrational lines of the molecules HeH$^+$, H$_2$, and CH$^+$ and more than 50 spectral lines of atoms and atomic ions.本文的重点是原子线排放，这是在之前的两个出版物中讨论的分子线（Neufeld等，2020，2021）。该调查涵盖的2.951-5.24微米区域（未完全）涵盖的2.951-5.24微米区域（1）六个碰撞的金属离子线组成（1）先前在天体物理星天体物理中已经鉴定出的金属离子的六个线索，但目前的观察结果提供了最准确的波长确定到日期，该原子线的原子线被置信度很高； （2）以前没有报道的4.6895微米处的光谱线，可能的标识为$^4f_ {7/2} - $ $ $^4f_ {9/2} $ [Zn VI]的精细结构过渡； （3）H和He $^+$的39条重组线，主量子数的上部最高38（h）或24（He $^+$）； （4）多电体物种He，C $^{2+} $和C $^{3+} $的10个重组线。
An infrared L- and M-band spectral survey, performed toward the young planetary nebula NGC 7027 with the iSHELL instrument on NASA's Infrared Telescope Facility (IRTF), has revealed more than 20 vibrational lines of the molecules HeH$^+$, H$_2$, and CH$^+$ and more than 50 spectral lines of atoms and atomic ions. The present paper focuses on the atomic line emissions, the molecular lines having been discussed in two previous publications (Neufeld et al. 2020, 2021). The atomic lines detected with high confidence in the 2.951 - 5.24 micron region covered (incompletely) by this survey comprise (1) six collisionally-excited lines of metal ions that had previously been identified in astrophysical nebulae but for which the present observations provide the most accurate wavelength determinations obtained to date; (2) a spectral line at 4.6895 micron, not previously reported, for which the probable identification is the $^4F_{7/2} - $ $^4F_{9/2}$ fine structure transition of [Zn VI]; (3) 39 recombination lines of H and He$^+$, with upper states of principal quantum number up to 38 (H) or 24 (He$^+$); (4) 10 recombination lines of the multielectron species He, C$^{2+}$, and C$^{3+}$.
