We present a catalog of 80 very wide fragile binary candidates (projected separations >10,000 AU) from the Sloan Digital Sky Survey Data Release Eight spectral archive. The pairs were selected based on proper motion, radial velocity, metallicity, and photometric parallax criteria. The angular separations of these pairs range from 3'' to 250''. The peak in the metallicity distribution of these pairs is about −0.5 dex of solar metallicity. Space motions and reduced proper motion diagrams indicate that all these pairs are members of the disk. The chromospheric activity index SHK of each component in 38 binary candidates having spectra of high signal-to-noise ratio and member stars of three open clusters (NGC 2420, M67, and NGC 6791) were measured. The SHK versus color relation for these binary candidates is consistent with the trend seen in these open clusters. The ages implied by this relation suggest that fragile wide pairs can survive longer than 8 Gyr.
The Astronomical Journal
Scholarly Commons Citation
Zhao, J., Oswalt, T. D., & Zhao, G. (2011). Fragile Binary Candidates in the SDSS DR8 Spectroscopic Archive. The Astronomical Journal, 143(2). https://doi.org/10.1088/0004-6256/143/2/31