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We present results from a Keck spectroscopic survey of red giants in a fieldnear M31's major axis, ~34kpc in projection from the nucleus, near the globularcluster G1. We use multislit LRIS spectroscopy to measure the CaII triplet in41 stars with apparent mags 20<I<22. Of these, 23 stars are found to haveradial velocities v<-200km/s indicating they are giants in M31; the rest areprobably foreground Galactic stars. About 2/3 of the M31 members concentrate atv=-451km/s, with a velocity spread of sigma=27km/s, which suggests that theybelong to the outer disk or perhaps a cold debris trail in the halo. Thegroup's mean velocity is consistent with that of nearby HI gas and models ofM31's disk velocity field but not with G1 or M31's systemic velocity. We useV,I photometry to estimate a mean metallicity of <[Fe/H]>=-0.8 for thesepotential M31 outer disk stars. Six of the 23 M31 members v and [Fe/H] valuesconsistent with those of G1 (after accounting forits intrinsic spread in both):one of these stars lies within G1's projected tidal radius and is a likelymember; the remaining 5 stars are not physically close to G1 but may representits tidal debris. More data are needed to confirm the nature of these 5 starsas it is likely that they represent M31's smooth halo population. We might haveexpected to detect tidal debris if G1 were the remnant core of a dwarf galaxybeing accreted by M31; instead, the majority of M31 giants in this field aremetal-rich and belong to what is evidently the outer disk of M31, and only asmall fraction (<~20%) could possibly have originated in G1.Comment: 11 pages, 2 figures, accepted for publication in the A

Keck Spectroscopy of Red Giant Stars in the Vicinity of M31'sMassive Globular Cluster G1