We present new measurements of photon energies and branching fractions for
the radiative transitions Y(2S) --> gamma chi(b(J=0,1,2))(1P). The masses o
f the chi(b) states are determined from the measured radiative photon energ
ies. The ratio of mass splittings between the chi(b) substates, r=(M-J=2-M-
J=1)/(M-J=1 - M-J=0), with M the chi(b) mass, provides information on the n
ature of the b (b) over bar confining potential. We find r(1P)=0.542 +/- 0.
022+/-0.024. This value is somewhat lower than the previous world average,
but more consistent with the theoretical expectation that r(1P)< r(2P); i.e
., that this mass splitting ratio is smaller for the chi(b)(1P) States than
for the chi(b)(2P) states. [S0556-2821(99)02903-3].