  We have studied the momentum dependence of the energy gap of Bi2(Sr,R)2CuOy
by angleresolved photoemission spectroscopy (ARPES), particularly focusing on
the difference between R=La and Eu. By comparing the gap function and
characteristic temperatures between the two sets of samples, we show that there
exist three distinct energy scales, {\Delta}pg, {\Delta}sc0, and {\Delta}eff
sc0, which correspond to T* (pseudogap temperature), Tonset (onset temperature
of fluctuating superconductivity), and Tc (critical temperature of coherent
superconductivity). The results not only support the existence of a pseudogap
state below T* that competes with superconductivity but also the duality of
competition and superconducting fluctuation at momenta around the antinode
below Tonset.
