Spin relaxation in GaAs/AlGaAs quantum wells in the vicinity of odd filling factors

Electron spin resonance in GaAs/AlGaAs quantum wells in the vicinity of odd filling factors $\nu=3,$, 5, and 7 is investigated. The spin relaxation time of two-dimensional electrons is determined from the width of the microwave resonance absorption line. Dependences of the spin relaxation time on the filling factor, temperature, and orientation of the magnetic field are investigated. The spin relaxation time decreases noticeably upon deviation from odd filling factors, and its maximum value depends on the angle between the magnetic field and the plane of the two-dimensional electron gas.