Cold Cores

Cold clumps and cold cores

The terms cold clumps and cold cores refer to dense and cold regions within interstellar molecular clouds. Clumps are typically larger than 0.1 pc and may contain further substructure. Cores are more compact, typically bound by gravity. The cores can collapse under their own self-gravity and thus form new stars. Prior to star-formation the objects are cold because they contain a lot of dust that shields the cores and clumps from the external heating by stars and, on the other hand, the interstellar medium cools via the radiation of the dust and of the molecules.

Cold cores also refers to the research projects that were conducted using the Planck and Herschel satellites. Planck mapped the whole sky at several submillimetre wavelengths. The observations were used to locate over 13000 cold objects all over the Milky Way. These are either clouds that may in the future form new stars or they may also be dense regions within already star-forming clouds. The Planck Galactic catalogue of Cold Clumps (PGCC) is described in the paper Planck Collaboration 2016: Planck 2015 results XXVIII.

The Herschel satellite was launched at the same time with Planck. It had a much higher spatial resolution than Planck and it also covered partly shorter wavelengths. We had an open time key programme Galactic Cold Cores which used Herschel for dedicated follow-up observations of the Planck clumps. This search will return most of the papers published on the analysis of those observations.

Cold Cores meetings

The Cold Cores project has had annual meetings since 2010. The program and presentations of the latest meetings can be found following these links.