skew mapping |
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![]() | the problem: | you want to detect the faint secondary star in your time-resolved data, but simply averaging the spectra together smears out any weak features from the star. |
![]() | a possible solution: | cross-correlate your time-resolved spectra with a template of matched spectral-type and then average the data with these velocity shifts removed. |
![]() | why this sometimes fails: | the secondary star features are too weak to give well-defined cross-correlation peaks. |
![]() | another possible solution: | back project the cross-correlation peaks to form a skew map (Smith, Collier Cameron, Tucknott, 1993, Cataclysmic Variables & Related Objects, eds Regev & Shaviv, IoP: Bristol, 70). |