Photometry, Spectrometry, and Polarimetry of FG Sge in the Active State

@article{Rosenbush2015PhotometrySA,
  title={Photometry, Spectrometry, and Polarimetry of FG Sge in the Active State},
  author={A. E. Rosenbush and Yu. S. Efimov},
  journal={Astrophysics},
  year={2015},
  volume={58},
  pages={46-61}
}
Photometric, spectral, and polarimetric observations of FG Sge during the stage of increasing activity in its R Coronae Borealis type variability are presented and analyzed. a weakening of the current level of rare transient states of maximum brightness is interpreted as a consequence of increasing optical thickness of a permanent circumstellar envelope. The brightness of the He1-5 nebula in the instrumental system in the Uc and V bands is 20m.69±0m.13 and 23m.01±0m.58 from a square arc second… 
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