Chemical Composition and Differential Time-Series CCD Photometry of V2314 Ophiuchi: A New λ Bootis-Type Star

We investigated V2314 Oph using high-resolution (R = 45,000) spectral observations. The atmospheric parameters were determined using iron-line abundance analysis. We derived a mean effective temperature of Teff = 7510 K, mean surface gravity of log g = 3.30, metallicity of [Fe/H] = -0.59, and rotation velocity of v sin i = 38 km s-1. The abundances of 19 chemical elements were determined. The abundance pattern of V2314 Oph was found to be similar to that of λ Bootis-type stars. V2314 Oph is also a variable star, as are a majority of λ Bootis stars. A frequency analysis of 10 selected nights of precise differential photometry has preliminarily revealed four pulsational modes. The multiperiodic solution of the light curve is probably more similar to a low-amplitude Population I δ Scuti variable pattern, as is apparent for many λ Bootis stars. For asteroseismic investigations of the star it is necessary to obtain more prolonged, continuous time-series observations. These features, as well as the small proper motion and relatively large rotational velocity of V2314 Oph, specify the star as not likely to be a field SX Phoenicis Population II variable, as was suggested previously.

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