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Planetary Nebulae Research

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 University of Texas- Austin is investigating molecular hydrogen in planetary nebulae by means of near-infrared spectroscopy of planetary nebulae. Observing trips to McDonald Observatory have allowed us to collect excellent data.

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:

frosty leo nebulaThe data shown here was obtained using the ARC 3.5m telescope at Apache Point in New Mexico. Below is a J band image of the planetary nebula NGC7027 obtained using the ARC telescope.



 

 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 .  
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