Rate Coefficients for the Collisional Excitation of Molecules: Estimates from an Artificial Neural Network

Details Rate Coefficients for the Collisional Excitation of Molecules: Estimates from an Artificial Neural Network Rate Coefficients for the Collisional Excitation of Molecules: Estimates from an Artificial Neural Network

2009-11-13

arxiv.org/abs/0911.2652v1

Astronomy and Astrophysics

Astrophysics

Instrumentation and Methods for Astrophysics

23 pages including 9 figures. Accepted for publication in ApJ

Scientific paper

An artificial neural network (ANN) is investigated as a tool for estimating rate coefficients for the collisional excitation of molecules. The performance of such a tool can be evaluated by testing it on a dataset of collisionally-induced transitions for which rate coefficients are already known: the network is trained on a subset of that dataset and tested on the remainder. Results obtained by this method are typically accurate to within a factor ~ 2.1 (median value) for transitions with low excitation rates and ~ 1.7 for those with medium or high excitation rates, although 4% of the ANN outputs are discrepant by a factor of 10 more. The results suggest that ANNs will be valuable in extrapolating a dataset of collisional rate coefficients to include high-lying transitions that have not yet been calculated. For the asymmetric top molecules considered in this paper, the favored architecture is a cascade-correlation network that creates 16 hidden neurons during the course of training, with 3 input neurons to characterize the nature of the transition and one output neuron to provide the logarithm of the rate coefficient.

Affiliated with

Also associated with

No associations

Rating

Rate Coefficients for the Collisional Excitation of Molecules: Estimates from an Artificial Neural Network does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Rate Coefficients for the Collisional Excitation of Molecules: Estimates from an Artificial Neural Network, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Rate Coefficients for the Collisional Excitation of Molecules: Estimates from an Artificial Neural Network will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-150041