Table 1: Steady-state charge distribution model results for dense clouds: Col. (1) is our standard model and Col. (5) is taken from FPdF03 for comparaison with our results. $n_{\rm g^-}$ ( $n_{\rm g^0}$, $n_{\rm g^+}$) is the number density of negative (neutral, positive) grains per unit volume, summed over all grain size bins. Idem for PAHs. The critical velocity  $V_{\rm crit}$ can be computed either by assuming that only the charged grains are strongly coupled to the magnetic field, as in FPdF03, or by following Eq. (12) based on the work of CRM04.
$n_{\rm H}$ (cm-3) 104 104 104 104 104 105 106
$n_{\rm PAH} / n_{\rm H}$ no PAH no PAH 10-6 10-6 10-6 no PAH no PAH
Secondary photons ? no yes no yes yes no no
  (1) (2) (3) (4) (5) (as per FPdF03) (6) (7)
$n_{\rm g^-}/n_{\rm g}$ 0.89 0.87 0.32 0.28 0.07 0.90 0.91
$n_{\rm g^0}/n_{\rm g}$ 0.11 0.11 0.67 0.68 0.90 0.10 0.09
$n_{\rm g^+}/n_{\rm g}$ 1 (-4) 4 (-4) 0.01 0.04 0.03 8 (-5) 7 (-5)
$n_{\rm PAH^-}/n_{\rm PAH}$     0.05 0.05 0.06    
$n_{\rm PAH^0}/n_{\rm PAH}$     0.95 0.95 0.94    
$n_{\rm PAH^+}/n_{\rm PAH}$     1 (-3) 1 (-3) 1 (-3)    
$n_{\rm i}/n_{\rm H}$ 3.38 (-8) 3.41 (-8) 5.50 (-8) 5.51 (-8) 6.50 (-8) 8.26 (-9) 1.75 (-9)
$n_{\rm e}/n_{\rm H}$ 3.38 (-8) 3.40 (-8) 2.53 (-9) 2.55 (-9) 2.68 (-9) 8.21 (-9) 1.70 (-9)
$V_{\rm crit}$ (FPdF03) 20.2 20.4 29.6 30.8 63 20.0 20.0
$V_{\rm crit}$ (CRM04) 20.7 20.8 22.9 23.7   23.6 28.1

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