Useful links
Locating research articles: ADS or astro-PH for pre-prints
Locating objects: SIMBAD
Locating info on a PN: VIZIER
Some wavelength lists: Atomic Line List, UKIRT
Near-infrared Observations of Planetary Nebulae
Research
with Anna Kindt and Kevin Bartig (UWEC undergraduate students) has involved
near-infrared observations at the wavelengths of the J, H and K bands. A
collaboration with astronomers at
Besides the molecular hydrogen that we are
most interested in, hydrogen in atomic form emits lines from several emission series, which show up in the near infrared
wavelength bands.
Likkel and Kindt have investigated the Frosty
Leo Nebula shown here in an H-band image:
The
data shown here was obtained using the ARC 3.5m telescope at Apache Point in
The
spectrum of the night sky at H-band is useful for
wavelength calibration. This particular spectrum is from July 1995.
Correction for atmospheric and instrumental
response:
An observation of a G-star, before correcting
for spectral response, shows clearly the shape of
the filter (H-band in this case) because the true spectrum has little
curvature. Atmospheric absorption at K-band causes
two "Absorption features" in the G-star, and thus in any object with
a continuum.
For spectral response correction
of near infrared data (to correct for atmospheric effects and instrumental
response) the recently
published method involving the solar spectrum holds much promise.
Other images of planetary nebulae
IC3568, K-band.
This is a single exposure, and although it has been corrected for detector
sensitivity variations, bad pixels have not been 'medianed' out.
A bipolar planetary nebula, NGC7026: NGC7026 in J band, and in H-band.
A large planetary nebula, NGC 6818 was
observed in H-band and J-band
.
