Which pulsar planet has the official name Draugr?

PSR B1257+12 b is the pulsar planet officially named Draugr.

The International Astronomical Union approved the name Draugr in December 2015 through its NameExoWorlds public naming campaign. In Norse mythology, a draugr is an undead being, an apt choice for a planet orbiting a pulsar—the dense, rapidly spinning remnant of a dead star.

PSR B1257+12 b is the innermost of three confirmed planets orbiting the millisecond pulsar PSR B1257+12, whose proper name is Lich. It was discovered through pulsar timing, a technique that detects tiny changes in the arrival times of the pulsar’s radio pulses as orbiting planets tug on it.

The system is historically important because the first two planets were announced in 1992, providing the first confirmed evidence of planets beyond the Solar System. Draugr is also exceptionally small: its mass is about twice that of Earth’s Moon. The neighboring planets PSR B1257+12 c and d are separate worlds and do not share the Draugr name.