We report the discovery of a bright ( m _ { V } = 11.6 mag ) eclipsing hot subdwarf binary of spectral type B with a late main sequence companion from the All Sky Automated Survey ( ASAS 102322-3737.0 ) .
Such systems are called HW Vir stars after the prototype .
The lightcurve shows a grazing eclipse and a strong reflection effect .
An orbital period of P = 0.13927 d , an inclination of i = 65.86 \degr , a mass ratio q = 0.34 , a radial velocity semiamplitude K _ { 1 } = 81.0 km s ^ { -1 } , and other parameters are derived from a combined spectroscopic and photometric analysis .
The short period can only be explained by a common envelope origin of the system .
The atmospheric parameters ( T _ { eff } = 28 400 K , \log { g } = 5.60 ) are consistent with a core helium-burning star located on the extreme horizontal branch .
In agreement with that we derived the most likely sdB mass to be M _ { sdB } = 0.46 M _ { \sun } , close to the canonical mass of such objects .
The companion is a late M-dwarf with a mass of M _ { comp } = 0.16 M _ { \sun } .
ASAS 102322-3737.0 is the third brightest of only 12 known HW Virginis systems , which makes it an ideal target for detailed spectroscopic studies and long term photometric monitoring to search for period variations , e.g .
caused by a substellar companion .