Astronomy and Astrophysics Evidence for a Signature of the Galactic Bar in the Solar Neighbourhood ⋆
نویسندگان
چکیده
Using available kinematical data for a sub-sample of NLTT stars from the HIPPARCOS mission we confirm the existence of a previously reported local anomaly in the (u, v) plane: the mean motion u for our sample is largely positive (+20 km s −1). With the use of the newest global self-consistent numerical models of our Galaxy (Fux 1997), we show that a bar could be responsible for this observed velocity anomaly. A fraction of our stars have bar perturbed " hot " orbits, allowing them to erratically wander from inside the bar to region outside corotation, in particular through the solar neighbourhood.
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