The time constants of the vibrational relaxation, upsilon = 2 -> upsilon = 1 and upsilon = 1 -> upsilon = 0, in the 1B(u)(+) manifold and those of internal conversion from the 1B(u)(-) (0) level, which is isoenergetic (so-called 'diabatic') with the 1B(u)(-) vibronic levels in neurosporene and spheroidene and with the 3A(g)(-) vibronic levels in lycopene and anhydrorhodovibrin, were determined by Kerr-gate fluorescence spectroscopy. The time constants of the vibrational relaxation were in the similar to 1:2 ratio, and those of internal conversion agreed with the life-times of the diabatic counterparts, i.e., the 1B(u)(-) u and 3A(g)(-) electronic states, respectively. (C) 2009 Elsevier B.V. All rights reserved.