Ammonia (J,K)=(1,1) to (4,4) and (6,6) inversion lines detected in the Seyfert 2 galaxy NGC 1068

Abstract

We present the detection of the ammonia (NH3) (J,K)=(1,1) to (4,4) and (6,6) inversion lines toward the prototypical Seyfert 2 galaxy NGC 1068, made with the Green Bank Telescope (GBT). This is the first detection of ammonia in a Seyfert galaxy. The ortho-to-para-NH3 abundance ratio suggests that the molecule was formed in a warm medium of at least 20K. For the NH3 column density and fractional abundance, we find (1.09 ± 0.23) × 1014 cm-2 and (2.9 ± 0.6) × 10-8, respectively, from the inner ∼1.2 kpc of NGC 1068. The kinetic temperature can be constrained to 80 ± 20 K for the bulk of the molecular gas, while some fraction has an even higher temperature of 140 ± 30 K. © 2011 ESO.