IR Spectroscopy of Nova-like Sources

Abstract

Near - IR spectroscopic and photometric observations of the eruptive variables V838 Mon and V445 Puppis in the J H K bands are reported. These objects erupted in nova-like explosions but evolved into rather unique and enigmatic objects. One of unusual features of the V838 Mon spectra is the detection of several strong TiI lines in emission in the K band. These spectra also show the strong presence of the 12CO bands. Deep water bands at 1.4 μm and 1.9 μm are also seen later in the object's evolution. Blackbody fits to the J H K photometric data show that V838 Mon evolves to low temperatures between 2400-2600 K after its outburst. The spectra of V 445 Puppis are found to be hydrogen deficient and unusually rich in CI lines leading to the possibility that it is a rare Helium nova. The nature of both the objects is discussed and it is shown that they do not fit into known categories of eruptive variables.