* Astronomy

Title: Radial velocity study of the CP star Epsilon Ursae Majoris
Authors: N.A. Sokolov

In this Letter, the radial velocity variability of the chemically peculiar star Epsilon Ursae Majoris (epsilon UMa) from the sharp cores of the hydrogen lines is investigated. This study is based on the ELODIE archival data obtained at different phases of the rotational cycle. The star exhibits low-amplitude radial velocity variations with a period of P=5.0887 d. The best Keplerian solution yields an eccentricity e=0.503 and a minimum mass ~14.7 Jupiter masses on the hypothesis that the rotational axis of epsilon UMa is perpendicular to the orbital plane. This result indicate that the companion is the brown-dwarf with the projected semi-amplitude variation of the radial velocity K_2 =135.9 km/sec and the sine of inclination times semi-major axis a_2 sin(i)=0.055 au.

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