On the Mass Ratio of TU Men

Radial velocities of TU Men measured from peaks of the emission lines are re-analyzed within the three-body approximation. The resulting crude estimate of the mass ratio is q=M₂/M₁=0.5±0.2. Using the mass of the secondary estimated from the M₂-P relation we obtain an independent lower limit q>0.41±0.08. These estimates exclude the possibility of superhumps being due to the tidal instability involving the 3:1 resonance which requires qcrit=0.25. The common belief that q_crit could be as high as q=0.33 is critically re-examined. It is shown that the results of numerical simulations, which form the basis of this belief, do not apply to situations encountered in the case of the observed superhumps.