Molecular gas and the fuelling of low luminosity radio galaxies

It is still not clear how classical radio sources are provided with fuel. At this moment there is some discussion if the fuelling is done by hot or by cold gas. If we want to get a definitive answer we will need detailed, high resolution and high sensitiviy observations of molecular clouds in the vicinity of the active nucleus. A breakthrough is to be expected only after the completion of at least a large part of the ALMA array of mm-telescopes that is being constructed right now in the Atacama desert in Chile. Nevertheless some first attempts are being done with the IRAM 30m telescope in France, and the new APEX telescope in Chile. Listed below are some articles relevant to the question of fuelling. All articles are in pdf format:

• A search for molecular gas in low luminosity radio galaxies
  (CO observations with the 30m IRAM telescope)
• A molecular gas study of low luminosity radio galaxies
  (CO observations with the 30m IRAM telescope)
• Is cold gas fuelling the radio galaxy NGC 315?
  (Neutral hydrogen absorption in the radio galaxy NGC 315)
• Molecular disks in southern radio galaxies. A Science verification project for APEX1
  (The search for CO in the nuclei of southern radio galaxies with the APEX telescope)
• Apex CO observations of southern radio galaxies
  (Accepted august 2010)