Strangulation as the primary mechanism for shutting down star formation in galaxies

Understand

Local galaxies are broadly divided into two main classes, star-forming (gas-rich) and quiescent (passive and gas-poor).

• The primary mechanism responsible for quenching star formation in galaxies and transforming them into quiescent and passive systems is still unclear.
• Sudden removal of gas through outflows or stripping is one of the mechanisms often proposed.
• An alternative mechanism is so-called "strangulation", in which the supply of cold gas to the galaxy is halted.