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arXiv · 2510.18528

The Optical Study of the Eclipsing Polar SDSS J002637.06+242915.6

V. Yu. Kochkina·A. I. Kolbin·T. A. Fatkhullin·A. S. Vinokurov·N. V. Borisov
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Abstract

We have analyzed phase-resolved photometric and spectroscopic observations of the eclipsing polar SDSS J002637.06+242915.6. The light curve has a M-shaped bright phase that was reproduced using a simple model of an accreting magnetic white dwarf. The hydrogen emission lines exhibit a narrow component formed on the irradiated hemispere of the donor. The Doppler tomography revealed differences in the positions of emission regions of hydrogen and HeII $\lambda$4686 lines. The spectra exhibit a Zeeman absorption triplet of the H$\alpha$ line, formed in the cold halo around the accretion spot at a magnetic field strength of $B = 15.1 \pm 1.3$ MG. The spectra of the bright phase have a red cyclotron continuum, whose orbital variability has been interpreted within a simple model of an accretion spot. The modeling of the cyclotron continuum constrains the white dwarf's magnetic field to $B_{cyc} \lesssim 45$ MG. The analysis of the eclipse light curve and the radial velocities of the irradiated hemisphere yielded estimates for the orbital inclination $77.2^\circ \le i \le 80.6^\circ$, the mass ratio $0.23 \le q \le 0.43$, and the white dwarf mass $0.72 \ge M_1/M_\odot \ge 0.42$.

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V. Yu. Kochkina, A. I. Kolbin, T. A. Fatkhullin, A. S. Vinokurov, N. V. Borisov. 2025-10-21. The Optical Study of the Eclipsing Polar SDSS J002637.06+242915.6. https://arxiv.org/abs/2510.18528

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