Chemically Tagging the HR 1614 Moving Group

We present abundances for a sample of F,G,K dwarfs of the HR1614 moving groupbased on high resolution, high S/N ratio spectra from AAT/UCLES. Our sampleincludes stars from Feltzing & Holmberg (2000, A&A, 357, 153), as well as fromEggen (1998, AJ, 115, 2453). Abundances were derived for Na, Mg, Al, Si, Ca,Mn, Fe, Ni, Zr, Ba, Ce, Nd, and Eu. The alpha, Fe, and Fe-peak elementabundances show a bimodal distribution, with four stars having solarmetallicities while the remaining 14 stars are metal rich [Fe/H] >= 0.25 dex.However the abundances of these two groups converge for the heavier n-captureelements. Based on their photometry and kinematics, three of the four deviatingstars are likely non-members or binaries. Although one star cannot be excludedon these grounds, we do expect low-level contamination from field stars withinthe HR1614 moving group's range of magnitude, color and space velocities.Disregarding these four stars, the abundance scatter across the group membersfor all elements is low. We find that there is an 80% probability that theintrinsic scatter does not exceed the following values: Fe 0.01; Na 0.08; Mg0.02; Al 0.06; Si 0.02; Ca 0.02; Mn 0.01; Ni 0.01; Zr 0.03; Ba 0.03; Ce 0.04;Nd 0.01 and Eu 0.02 dex. The homogeneity of the HR 1614 group in age andabundance suggests that it is the remnant of a dispersed star-forming event.Its kinematical coherence shows that such a dispersing system need not besignificantly perturbed by external dynamical influences like galactic spiralstructure or giant molecular clouds, at least over a period of 2 Gyr.Comment: 7 figures, Accepted by A