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arXiv · 2004.11764

Possibilities of Using Middle-Band Filters to Search for Polar Candidates

M. M. Gabdeev·T. A. Fatkhullin·N. V. Borisov
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Abstract

We present a method for searching for polar candidates using mid-band filters. One of the spectral singularities of polars is the $HeII \lambda4686$\AA~ strong emission line. We selected the Edmund Optics filters with central wavelengths of 470, 540, and 656 nm and a transmission bandwidth of 10 nm. These filters cover the regions of the $HeII \lambda4686$\AA~ line, continuum, and the $H_\alpha$ line respectively. We constructed a color diagram based on the available spectra of polars and objects with a zero redshift from the SDSS archive. We show that most polars make a group with unique color indices. In practice, the method is implemented in SAO RAS at the Zeiss-1000 telescope with a new multi-mode photometer-polarimeter (MMPP). Approbation of the method with the known polars allowed us to develop two criteria to select candidates with an efficiency of up to 75\%.

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M. M. Gabdeev, T. A. Fatkhullin, N. V. Borisov. 2020-04-24. Possibilities of Using Middle-Band Filters to Search for Polar Candidates. https://doi.org/10.1134/s1990341320030037

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