This online C_{2} 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 C_{2} 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.