Interstellar absorption features of molecular species

Lines connect the coordinator with its partners.

Project objective

Interstellar (IS) molecules have been discovered in thirties of the XXth century but for three decades considered as a rather marginal constituent of IS clouds. Only about 10 of them carry observable IS lines, allowing to probe homogeneous media of individual absorbing clouds. In the same clouds one can observe about 300 diffuse interstellar bands (DIBs); their identification remains the longest standing unsolved problem in all of spectroscopy. Current hypotheses connect them with carbon and hydrogen bearing, complicated molecules. The simplest, H_2 and C_2 molecules are very likely building blocks for more complicated species The first one is actively investigated in Catania; the second is a subject of intensive observations of JK. It is important to relate the simple species to the unidentified diffuse bands. This may allow to solve the long standing problem of the identification of the latter. The applicant collected already many spectra in which DIBs are seen. This database is to be transferred to Catania. Additional, ground-based observations should also allow to include longer carbon chains (C_3, C_5) into considerations; this should be a good test of the Douglas hypothesis, connecting DIBs with bare carbon chains. We would consider the possible common formation of H_2 and DIB carriers on e.g surfaces of dust grains.

Original text from CORDIS.

Participants

• UNIVERSITY OF CATANIA · CATANIACoordinatorItaly

Links

• View on CORDIS