Mass and F3, o/F_ decay branching ratio of the q-meson 77 from the p(?,, q)p reactmn

Near threshold photoproduction of rl-mesons from the proton has been measured at the MAMI accelerator with the TAPS spectrometer, The mass of the r/-meson was de- duced from the threshold energy for ~/-photoproduction. The result of mn=(547.12 ~ 0.06 :t: 0.25) MeV supports the low value of the rl-mass reported from a dp -+ 3Her/measure- ment at SATURNE in 1992. The rl-decay branching ratio F3,~o/FT.y was measured to be (0.832 -t-0.005 4-0.012).