The asynchrony of the polar SDSS~J085414.02+390537.3 was revealed using the data of ZTF photometric survey. The light curves show a beat period Pbeat=24.6±0.1~days. During this period the system changes its brightness by ∼3m. The periodograms show power peaks at the white dwarf's rotation period Pspin=113.197±0.001~min and orbital period Porb=113.560±0.001~min with the corresponding polar asynchrony 1−Porb/Pspin=0.3%. The photometric behavior of the polar indicates a change of the main accreting pole during the beat period. Based on the Zeeman splitting of the Hβ line, an estimate of the mean magnetic field strength of the white dwarf is found to be B=28.5±1.5~MG. The magnetic field strength B≈34~MG near the magnetic pole was found by modeling cyclotron spectra. Doppler tomograms in the Hβ line demonstrate the distribution of emission sources typical for polars.
@article{arxiv.2308.04597,
title = {SDSS J085414.02+390537.3 -- a new asynchronous polar},
author = {A. I. Kolbin and M. V. Suslikov and V. Yu. Kochkina and N. V. Borisov and A. N. Burenkov and D. V. Oparin},
journal= {arXiv preprint arXiv:2308.04597},
year = {2023}
}