1997A&A...320..181S

We present phase-resolved spectroscopy of the eclipsing AM Herculis star UZ For obtained when the system was in its low state of accretion. Faint residual Hα-emission and NaI absorption were used to trace the secondary star and infer its orbital velocity K₂. The measured radial velocity amplitude of NaI K₂*sini=285±50km/s suggests a low-mass white dwarf with M_wd=0.44±0.15M_☉ (1σ-errors). The Hα emission line on the other hand, visible only for part of the orbital cycle and supposed to originate only on the illuminated hemisphere facing the white dwarf, displays a similar radial velocity amplitude, K'₂sini=308±27km/s. The standard K₂-correction applied by us then suggests a white dwarf mass of up to 1M_☉ . Compared with earlier results the new ones enlarge the window in which the white dwarf mass may lie and resolves the conflict between mass estimates based on photometry and spectroscopy. They leave some ambiguity in the location of emission and absorption components in these and former observations.