The spectral energy distribution ( SED ) of the TT Ari system , which is well known from published IUE and optical photometric observations , was modeled by a steady-state accretion \alpha -disc around a white dwarf .
Parameters of the system were derived from time-resolved optical spectral observations in the bright state that we obtained in Sep. 1998 .
The radial velocity semi-amplitude of the white dwarf ( 33.8 \pm 2.5 km s ^ { -1 } ) and corresponding mass function ( f ( M ) = 5.5 \pm 1.2 ~ { } \times 10 ^ { -4 } ~ { } M _ { \odot } ) were derived from the motion of the emission components of Balmer lines .
The mass ratio q ( \approx 0.315 ) was evaluated from the fractional period excess of the superhump period over the orbital period \varepsilon ( \approx 0.085 ) , and a secondary mass range ( 0.18 - 0.38 M _ { \odot } ) was estimated from the orbital period .
Therefore , the white dwarf mass range is 0.57 - 1.2 M _ { \odot } and the inclination angle of the system to the line of sight is 17 – 22.5 degrees .
The adopted distance to the system is 335 \pm 50 pc .
To fit the observed SED it is necessary to add a thermal spectrum with T \approx 11600 K and luminosity \approx 0.4 L _ { d } to the accretion disc spectrum .
This combined spectrum successfully describes the observed Balmer lines absorption components .
Formally the best fit of the HeI 4471 line gives minimum masses of the components ( M _ { RD } = 0.18 M _ { \odot } and M _ { WD } = 0.57 M _ { \odot } ) , with the corresponding inclination angle i = 22. ^ { \circ } 1 and mass-accretion rate \dot { M } = 2.6 \times 10 ^ { 17 } g s ^ { -1 } .