We begin by discussing the accuracy of the computed electronic states. The vertical ionization energy for the first excited state, E , computed using the composite method described above, is 12.827 eV. Our error estimate for this value is 30 meV (see Table for details). We note that the convergence of the vertical gap between the two states is much faster and this value is estimated as 123±8 meV (see Table for details). Peak A is known to be a hot band, and does not appear in our (0 K) simulation. The simulation reproduces well the consecutive increase in the intensities of peaks B, C, D, and E as well as the spacing between these peaks. The drop in the intensity at peak F is captured by the simulation. Starting from peak G, the simulation shows discrepancy with the experiment. A sudden drop in the intensity past peak H is not observed in the simulation. We discuss a likely source of this mismatch below. Our simulation allows for an additional element of analysis-Figure shows a decomposition of the simulated spectrum from Figure . All lines that contribute to the spectrum are marked individually and are color-coded indicating which electronic state's transition intensity the peak draws from. The total envelope of the spectrum is also decomposed showing contributions from each state. Our simulation locates the minimum of the conical intersection (marked as CI) at 3,174 cm -1 above the origin (12.92 eV), where origin means the lowest energy peak appearing in the spectrum. The adiabatic energy gap between the two lowest vibrational states in each of the cation states is T 00 =1,368±65 cm -1 .