This online C2 calculator consists of two pages. The first allows you to convert observed equivalent widths to column densities, using the oscillator strengths of van Dishoeck and Black (ApJ 340, 273 (1989)). The second uses the method of van Dishoeck and Black (ApJ 258, 533, 1982) to compute the rotational distribution of C2 for a grid of (n,T) points you specify. The calculator then determines the "best fit" values of (n,T) for the column densities N(J) you input. It also provides useful graphs which can be used to see how well-constrained the fit is by your observational data, given the uncertainties.
Convert equivalent widths to column densities
Convert column densities to n and T
If you use this calculator for a publication, please acknowledge your use of this service.
If these pages generate errors, please notify Ben McCall by email at bjmccall@scs.uiuc.edu.