Intermediate polar

An Intermediate Polar (also DQ Herculis Star) is a type of cataclysmic variable binary star system. In most cataclysmic variables, matter from a main-sequence companion star is gravitationally stripped by a white dwarf star in the form of an accretion disk. In intermediate polar systems, the accretion disk is disrupted by the magnetic field of its white dwarf star. Infalling gas from the companion star will form a disk when the matter is still far from the white dwarf, but will follow magnetic field lines in accretion streams when the matter falls closer to the white dwarf. In the transition region between the accretion disk and the accretion stream, infalling gas may also fall as curved sheets called accretion curtains.