A search for β Pictoris-like Ca II circumstellar gas around Ursa Major Stream stars

We carried out an optical spectroscopic survey of twenty one stars to search for Ca II circumstellar gas at the stellar velocity similar to that found in the β Pictoris disk. The surveyed stars are A-type stars with large v sin i in the Ursa Major stellar kinematic group. No evidence of circumstellar gas was found around any of the stars. This result suggests that β Pictoris either is a very peculiar object surrounded by an anomalous amount of gas, or is younger than the stars in the Ursa Major Group (∼ 3 10⁸ years).