| |
 |
| Paper: |
A New Sky Subtraction Technique for Low Surface Brightness Data |
| Volume: |
442, Astronomical Data Analysis Software and Systems XX (ADASSXX) |
| Page: |
143 |
| Authors: |
Katkov, I. Y.; Chilingarian, I. V. |
| Abstract: |
We present a new approach to the sky subtraction for long-slit spectra that is
suitable for low-surface brightness objects based on the controlled
reconstruction of the night sky spectrum in the Fourier space using twilight
or arc-line frames as references. It can be easily adopted for
FLAMINGOS-type multi-slit data. Compared to existing sky subtraction
algorithms, our technique is taking into account variations of the spectral
line spread along the slit thus qualitatively improving the sky subtraction
quality for extended targets. As an example, we show how the stellar metallicity and
stellar velocity dispersion profiles in the outer disc of the spiral galaxy
NGC5440 are affected by the sky subtraction quality. Our technique is used
in the survey of early-type galaxies carried out at the Russian 6-m
telescope, and it strongly increases the scientific potential of large
amounts of long-slit data for nearby galaxies available in major data
archives. |
|
|
|
|
|
