Search for Stellar Streams Based on Data from the RAVE5 and Gaia TGAS Catalogues

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We have analyzed the space velocities of stars with the proper motions and trigonometric parallaxes from the Gaia TGAS catalogue in combination with the line-of-sight velocities from the RAVE5 catalogue. In the (V,√U²+2V²) velocity plane we have identified three clumps, BB17-1, BB17-2, and BB17-3, in the region of large velocities (V<-150 km/s). The stars of the BB17-1 and BB17-2 clumps are associated with the kinematic groups VelHel-6 and VelHel-7 detected previously by Helmi et al. We give the greatest attention to the BB17-3 clump. The latter is shown to be most closely linked with the debris of the globular cluster ωCen. In the BB17-3 clump we have identified 28 stars with a low velocity dispersion with respect to the center of their distribution. All these stars have very close individual age estimates: t≈ 10. The distribution of metallicity indices in this sample is typical for the stars of the globular cluster ωCen. In our opinion, the BB17-3 clump can be described as a homogeneous stream in the debris of the cluster ωCen.