Spectroscopic and photometric study of the new eclipsing polar Gaia23cer (2409.15570v1)

Abstract: We present the results of the optical study of the new eclipsing polar Gaia23cer. We analyzed the brightness variability of the polar in high ($\langle r \rangle \approx 16.5\mathrm{\,mag}$) and low ($\langle r \rangle \approx 19.2\mathrm{\,mag}$) states. The system has an orbital period $P_{orb} = 102.0665 \pm 0.0015$ min and exhibits deep eclipses with a duration $\Delta t_{ecl} = 401.30 \pm 0.81$ s. The spectra have a red cyclotron continuum with the Zeeman H$\alpha$ absorption triplet forming in a magnetic field with a strength of $15.2 \pm 1.1$ MG. The source of emission lines has a high radial velocity semiamplitude ($K\approx 450$km/s) and its eclipse lags behind the eclipse of the white dwarf. The mass $M_1=0.79 \pm 0.03 M_{\odot}$ and temperature $T=11350 \pm 650 K$ of the white dwarf have been found by modelling the spectral energy distribution. The eclipse duration corresponds to a donor mass $M_2 = 0.10-0.13M_{\odot}$ and an orbital inclination $i=84.3-87.0^{\circ}$. The donor temperature was estimated to be $T\approx 2900K$ by modelling the elliptical variability and eclipse depth.