The article "A search for cool molecular gas in GK Persei and other classical novae", by Tomasz Kaminski (CAMK PAN), Helena J. Mazurek (Nicolaus Copernicus Unversity, Toruń), Karl M. Menten (Max Planck, Bonn) and Romuald Tylenda (CAMK PAN) presents results of a search for molecular matter around classical novae using millimeter-wave telescopes and interferometers. The search was motivated by an investigation of an isotopic composition of matter enhanced in products of a nuclear runaway which takes place on a surface of a white dwarf. Even though observations were obtained for nearly one hundred classical novae in transitions of the HCN and CO molecules, not a single object was found with an observable amount of cool molecular gas. Additionally, the authors took a closer look at the surroundings of a classical nova from 1901, known today as GK Per. They found only molecular emission that arises in a nearby interstellar cloud. The cloud was probably the medium that gave rise to the light echo that was observed shortly after the 1901 outburst of GK Per.
Although so far no one has found a cool molecular component in nova ejecta, future observations of nearby classical novae with the ALMA interferometer have a chance to detect molecules and yield their isotopic composition. This, in turn, will pave the way to better understand the nucleosynthesis of the nova runaway.
Figure: The infrared image of GK Per shows a bipolar nebula (outlined in blue) surrounding the nova. The molecular emission from the nearby molecular cloud is shown with red contours.
The article will soon be published in Astronomy & Astrophysics.
Text: Tomasz Kamiński
