Modeling of IRAS Detections of Classical Novae

and Related Objects

by Thomas Edward Harrison

Under the supervision of Professor Robert Gehrz


Our project involved extracting data on classical novae from the Infrared Astronomical Satellite (IRAS) database, and evolving models to explain the resulting detections. We also extracted data on objects which have behavior similar to classical novae.
For the 105 novae or suspected novae in our sample, we report detections for 53 of them.. Eleven of these appear to be "false" detections of the galactic cirrus. To explain the remaining detections, we have developed several computer programs that model the ejected gas using published data on the conditions expected in post-outburst nova ejecta. The result of these programs is a prediction of the far-infrared line spectrum emitted by the gas ejected in the nova explosion. We are able to explain a number of the detections made by IRAS this way. In several cases, emission from dust or free-free processes can be invoked to explain the IRAS data.
We have also extracted information from the IRAS database for 116 objets related to novae. Such objects as dwarf novae, nova-like variables, symbiotic stars and cataclysmic planetary nebulae are included as related objects. many of these objects were detected (93), and the resultant energy distributions were compared to those found for novae to determine if there are similarities among the different classes of cataclysmic variables. The source of the infrared energy for the dwarf novae and nova-like variables remains difficult to explain.