M. Meixner et al., 2-12.5 MICRON IMAGING OF IRAS 21282- THE STRUCTURE OF A YOUNG PLANETARY-NEBULA(5050 ), The Astrophysical journal, 411(1), 1993, pp. 266-273
We present 3.3, 8.5, 10.0, 11.3, and 12.5 mum narrow-band (DELTAlambda
/lambda almost-equal-to 3%-10%) and K-band (2.2 mum) high spatial reso
lution images of IRAS 21282 + 5050 and a 6 cm flux density measurement
. The new infrared images reveal a toroidal dust nebula, 4.5'' x 6'',
P.A. 165-degrees, with two prominent emission peaks aligned almost E-W
and separated by 1''.7-2''.1; a remarkably similar structure to that
observed in NGC 7027. From the 6 cm flux density and the dust nebula s
ize, we derive an electron density of 3.6 x 10(3) cm-3 for the central
ionized region. Comparison of these images with a published CO 1-0 ma
p suggests that the structure of this dusty, ionization-bounded planet
ary nebula may reflect the density inhomogeneities of the progenitor's
wind. Only slight spatial differences are discernible between the K-b
and and 10 mum ''dust'' continuum images and the 3.3, 11.3, and 12.5 m
um unidentified infrared (UIR) emission-band images which have been at
tributed to polycyclic aromatic hydrocarbons (PAHs). This tight spatia
l correlation suggests that the K-band and 10 mum emission also arises
from PAHs.