ON THE CORRELATION OF TORQUE AND LUMINOSITY IN GX-1+4

Over 5 years of daily hard X-ray (> 20 keV) monitoring of the 2 minute accretion-powered pulsar GX 1+4 with the Compton Gamma Ray Observator y/BATSE large-area detectors has found nearly continuous rapid spin-do wn, interrupted by a bright 200 day spin-up episode. During spin-down, the torque becomes more negative as the luminosity increases (assumin g that the 20-60 keV pulsed flux traces bolometric luminosity), the op posite of what is predicted by standard accretion torque theory. No ch anges in the shape of the 20-100 keV pulsed energy spectrum were detec ted, so that a very drastic change in the spectrum below 20 keV or the pulsed fraction would be required to make the 20-60 keV pulsed flux a poor luminosity tracer. These are the first observations that flatly contradict standard magnetic disk accretion theory, and they may have important implications for understanding the spin evolution of X-ray b inaries, cataclysmic variables, and protostars. We briefly discuss the possibility that GX 1+4 may be accreting from a retrograde disk durin g spin-down, as previously suggested.