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We report on our large scale search of 2MASS and SuperCOSMOS in the southern hemisphere for very widely separated white dwarf / L-dwarf binary systems and present our findings, including 8 widely separated candidate systems, and proper motion analysis confirming one of these as a widely separated white dwarf/ L-dwarf common proper motion binary candidate.
We present the discovery of the widest known ultracool dwarf - white dwarf binary. This binary is the first spectroscopically confirmed widely separated system from our target sample. We have used the 2MASS and SuperCOSMOS archives in the southern he
We identify 806 ultra-cool dwarfs from their SDSS riz photometry (of which 34 are newly discovered L dwarfs) and obtain proper motions through cross matching with UKIDSS and 2MASS. Proper motion and distance constraints show that nine of our ultra-co
The majority of stars in the Galactic field and halo are part of binary or multiple systems. A significant fraction of these systems have orbital separations in excess of thousands of astronomical units, and systems wider than a parsec have been iden
A large population of fragile, wide (> 1000 AU) binary systems exists in the Galactic field and halo. These wide binary stars cannot be primordial because of the high stellar density in star forming regions, while formation by capture in the Galactic
We present the discovery of the shortest-period, non-interacting, white dwarf-brown dwarf post-common-envelope binary known. The K2 light curve shows the system, EPIC 21223532 has a period of 68.2 min and is not eclipsing, but does show a large refle