Reply To: CG Dra: a VSS campaign

Forums Variable Stars CG Dra: a VSS campaign Reply To: CG Dra: a VSS campaign

Maxim Usatov

CG Dra fading, pair of eclipses visible, medium quality data. The latter appears to be of U/N/A type – U-shaped, normal orbital hump height, asymmetric. The former eclipse was interrupted by clouds, so the shape is indistinguishable, filed it as ?/N/A. Both types expected during the fading stage.

I have also updated the eclipse type table. I have removed the Broad-U/N/A type, as it appears to be the same as U/N/A, measured eclipse widths – the differences appear to be insignificant. I am also beginning to suspect that U/N/A and V/N/A, and U/L/S and V/L/S represent the same events, except that V-shaped counterparts simply exhibit more flickering during the minima or it is simply a chance alignment of measurement points that produce the V shape. I will leave them as separate types for now, but they are probably candidates for merger.

This data also uses new calibration files, had to redo everything for -15C Moravian C3-61000 main sensor cooling, as the -20C setpoint was pushing the coolers way too much – it’s pretty warm in Sierra del Segura mountains even during the night time. I was waiting to shoot flats for a few weeks. We should have gone for the enhanced cooling option, but we’ll live with -15C for now.