Cooling dynamics of photo-excited negative carbon cluster ions stored in an ion storage ring

摘要

A newly found fast radiative cooling process of C_6~- is studied by simulation based on statistical sharing of the internal energy by the vibrational modes both in the electronic ground and excited states. For comparison, a contrasting slow cooling of C_6H~- is simulated by the same procedure. The simulation demonstrates a distinct difference in the time evolution of energy distributions between C_6~- and C_6H~-, and well reproduces the observed fast cooling of C_6~- by recurrent electronic transitions and the slow cooling of C_6H~- by vibrational de-excitation.