▁of ▁evolution ary ▁models ▁to ▁the ▁observed ▁physical ▁properties ▁to ▁determine ▁an ▁evolution ary ▁mass ▁as ▁well ▁as ▁the ▁age ▁of ▁the ▁stars ; ▁or ▁determ ination ▁of ▁a ▁dynam ical ▁mass ▁from ▁the ▁orb ital ▁mot ions ▁of ▁the ▁stars . ▁The ▁spect ro scop ic ▁masses ▁found ▁for ▁each ▁component ▁of ▁ σ ▁Or ion is ▁have ▁large ▁marg ins ▁of ▁error , ▁but ▁the ▁dynam ical ▁and ▁spect ro scop ic ▁masses ▁are ▁considered ▁accurate ▁to ▁about ▁, ▁and ▁the ▁dynam ical ▁masses ▁of ▁the ▁two ▁components ▁of ▁ σ ▁Or ion is ▁A ▁are ▁known ▁to ▁within ▁about ▁. ▁However , ▁the ▁dynam ical ▁masses ▁are ▁all ▁larger ▁than ▁the ▁evolution ary ▁masses ▁by ▁more ▁than ▁their ▁marg ins ▁of ▁error , ▁indicating ▁a ▁system ic ▁problem . ▁This ▁type ▁of ▁mass ▁dis cre p ancy ▁is ▁a ▁common ▁and ▁long - standing ▁problem ▁found ▁in ▁many ▁stars . ▁ ▁A ges ▁Com parison ▁of ▁the ▁observed ▁or ▁calculated ▁physical ▁properties ▁of ▁each ▁star ▁with ▁theoretical ▁stell ar ▁evolution ary ▁tracks ▁allows ▁the ▁age ▁of ▁the ▁star ▁to ▁be ▁estimated . ▁The ▁estimated ▁ages ▁of ▁the ▁components ▁A a , ▁Ab , ▁and ▁B , ▁are ▁respectively ▁ ▁My r , ▁ ▁My r , ▁and ▁ ▁My r . ▁Within ▁their ▁large ▁marg ins ▁of ▁error , ▁these ▁can ▁all ▁be ▁considered ▁to ▁be ▁consistent ▁with ▁each ▁other , ▁although ▁it ▁is ▁harder ▁to ▁recon cile ▁them ▁with ▁the ▁ 2 - 3 ▁My r ▁estimated ▁age ▁of