Procedure
Observations:
Observations were done with the 16" LX200GPS Schmidt-Cassegrain telescope at Rice University. The primary observations were three 10-minute (600 second) exposures of the Eskimo or Clown Face nebula, NGC 2392.
20 second exposures were taken of the spectrophotometric standard star HR3454 and mercury and neon lamps (reflected off of sheets of paper). HR3454 is at approximately the same airmass as the Eskimo nebula.
In order to determine the positioning of the spectral images, a 5 second exposure of Beta Gemini was taken.
Multiple 600 second, 120 second, and 20 second darks and a 600 second sky exposure were taken along with multiple flat field images.
Image Reduction and Analysis:
All .fit images were converted to .imh images for use in IRAF.
Darks were combined using imcombine
Flats were combined using imcombine
The combined dark was subtracted from the primary images and the sky image
A 5x5 boxcar smoothing routine was run on the flat image, and then the flat was divided by the boxcar flat to get a normalized flat
The sky and primary images were then divided by the normalized flat
The primary images were then shifted using imshift so that they would be properly aligned (and aligned with the Beta Gemini image)
The final sky was subtracted from the primary images
The primary images were then combined to a final two-dimensional spectra of the Eskimo nebula
Spectral Analysis:
** The final eskimo nebula image was copied and shifted by 15 and 35 pixels in order to analyze the inner and outer nebula compositions
Apall was used with an nsum value of 3 to extract one-dimensional spectra from the three nebula images using Beta Gemini as a reference
The mercury and neon images were combined, then apall was used to extract their one-dimensional spectra. The identify function was used to identify the mercury and neon spectral lines. The wavelength solution from this process was used to apply a dispersion solution to the extracted images using the dispcor function.
Apall was used with no referent to extract a one-dimensional spectrum of the spectrophotometric standard star HR3454.
The standard task and star HR3454 were used to make a standard calibration table, which was subsequently used to fit a calibration function using 'sensfunc'.
The function acquired was used to calibrate the extracted, dispcor'd images
Spectra flux measurements:
Using spectool and the 'k' key, the flux of different spectral lines were measured