High Resolution Near-IR Spectroscopy of Hubble 12

Previous abstract Next abstract

Session 47 -- Planetary Nebulae
Display presentation, Tuesday, 10, 1995, 9:20am - 6:30pm

[47.06] High Resolution Near-IR Spectroscopy of Hubble 12

Kevin Luhman (Steward Observatory)

High resolution spectra at H(1.6 $\mu$m) and K(2.2 $\mu$m) have been obtained of the young planetary nebula Hubble 12, using the long-slit near-infrared spectrometer FSpec. The prominent features in these rich spectra include emission from the Brackett and Pfund series of hydrogen, [Fe II], He I, and $H_2$. Previous studies of Hubble 12 in the near-infrared have focused on $\sim$10 molecular hydrogen lines at the K window which indicate flourescent emission. Our high resolution spectra (R=3500) have revealed 50 $H_2$ lines at both H and K. Transitions from levels as high as v=12 clearly indicate fluorescent excitation. The large number of detected $H_2$ lines allows us to compare in detail the observed strengths to those predicted by models of fluorescent emission. We conclude that the gas density in the outer regions of the nebula is close to $n_H$=3.0x$10^3$ $cm^{-3}$ and definitely less than the critical density, which is $n_c$=$10^4$- $10^5$$cm^{-3}$. We will study the emission lines from H, He I, and [Fe II] to obtain electron temperatures and densities for regions closer to the central star.

Tuesday program listing