Recent Results on Two-Photon and tau Physics at BABAR

We present a measurement of the total width {Lambda}{sub tot}{sup {eta}{sub c}} and mass M{sub {eta}{sub c}} of the {eta}{sub c} meson with the BABAR detector at the PEP-II B-factory at SLAC. The results based on a data sample of 88 fb{sub -1} are {Lambda}{sub tot}{sup {eta}{sub c}} = (33.3 {+-} 2.5(stat.) {+-} 0.8(sys.))MeV/c{sup 2} and M{sub {eta}{sub c}} = (2983.3 {+-} 1.2 {+-} 1.8) MeV/c{sup 2}. An enhancement observed around 3.63 GeV/c{sup 2} can be interpreted as an evidence for the {eta}{sub c}(2S) state. In addition a preliminary measurement of the {tau} lepton lifetime using 30.2 fb{sup -1} is described. The measured {tau} lifetime is: {tau}{sub {tau}} = (290.8 {+-} 1.5(stat.) {+-} 1.6(syst.)) fs.