  We performed angle resolved photoelectron spectroscopy (ARPES) studies on
mechanically detwinned BaFe2As2. We observe clear band dispersions and the
shapes and characters of the Fermi surfaces are identified. Shapes of the two
hole pockets around the {\Gamma}-point are found to be consistent with the
Fermi surface topology predicted in the orbital ordered states. Dirac-cone like
band dispersions near the {\Gamma}-point are clearly identified as
theoretically predicted. At the X-point, split bands remain intact in spite of
detwinning, barring twinning origin of the bands. The observed band dispersions
are compared with calculated band structures. With a magnetic moment of 0.2 ?B
per iron atom, there is a good agreement between the calculation and
experiment.
