const XHe = 0.1
const omega = 0.5;
const SEC_PER_YEAR = 31556952.0


const INTEGRATE = true  # 1 = integration, 0 = root-finding (TODO)

const ξ0 = 1.36e-17
const kdust = 3e-17
const kH2diss = 5.68e-11 * 0.52
const kCOdiss = 2.43e-10 * 0.48
const gamma_H2 = 3.85
const gamma_CO = 3.51
