New tidal debris nearby the Sagittarius leading tail from the LAMOST DR2
  M giant stars
  We report two new tidal debris nearby the Sagittarius (Sgr) tidal stream in
the north Galactic cap identified from the M giant stars in LAMOST DR2 data.
The M giant stars with sky area of $210^\circ<$\Lambda$<290^\circ$, distance of
10--20kpc, and [Fe/H]$<-0.75$ show clear bimodality in velocity distribution.
We denote the two peaks as Vel-3+83 for the one within mean velocity of
-3kms$^{-1}$ with respect to that of the well observed Sgr leading tail at the
same $\Lambda$ and Vel+162+26 for the other one with mean velocity of
162kms$^{-1}$ with respect to the Sgr leading tail. Although the projected
$\Lambda$--$V_{gar}$ relation of Vel-3+83 is very similar to the Sgr leading
tail, the opposite trend in $\Lambda$--distance relation against the Sgr
leading tail suggests Vel-3+83 has a different 3D direction of motion with any
branch of the simulated Sgr tidal stream from Law & Majewski. Therefore, we
propose it to be a new tidal debris not related to the Sgr stream. Similarly,
the another substructure Vel+162+26, which is the same one as the NGC group
discovered by Chou et al., also moves toward a different direction with the Sgr
stream, implying that it may have different origin with the Sgr tidal stream.
