SIMBAD references

Spectral data are presented for comets 2006 VZ13 (LINEAR), 2006 K4 (NEAT), 2006 OF2 (Broughton), 2P/Encke and 93P/Lovas I, obtained with the Cerro Tololo Inter-American Observatory 1.5-m telescope in 2007 August. Comet 2006 VZ13 is a new Oort cloud comet and shows strong lines of CN (3880 Å), the Swan band sequence for C₂(4740, 5160 and 5630 Å), C₃(4056 Å) and other faint species. Lines are also identified in the spectra of the other comets. Flux measurements of the CN, C₂(Δv = +1, 0) and C₃ lines are recorded for each comet and production rates and ratios are derived. When considering the comets as a group, there is a correlation of C₂and C₃ production with CN, but there is no conclusive evidence that the production rate ratios depend on heliocentric distance. The continuum is also measured, and the dust production and dust-to-gas ratios are calculated. There is a general trend, for the group of comets, between the dust-to-gas ratio and heliocentric distance, but it does not depend on dynamical age or class. Comet 2006 VZ13 is determined to be in the carbon-depleted (or Tempel 1 type) class.