Low-mass white dwarfs need friends: five new double-degenerate close binary stars

We have discovered five detached close binary stars out of seven white dwarfs chosen for their low mass (<0.45 Mʘ). The high success rate of our observations supports the notion that evolution within a binary star is needed to obtain white dwarfs with masses below 0.45 Mʘ. We have measured the orbit... View More