The antigenic formula for S. Typhi is O 9,12 H d (Vi). I'm not aware of anyone using LPS , flagellar or capsule antigens to actually detect S. Typhi as none of the antigens is completely specific to the serovar- ideally it should be detected by culture or potentially specific PCR. Vi capsule can be found on Salmonella Dublin too which is not widely known by clinicians.