The slow death of most galaxies

TL;DR

This paper investigates the prolonged process of star formation shutdown in most galaxies, attributing it mainly to environmental effects like strangulation over a span of four billion years.

Contribution

It provides evidence that strangulation by environment is the primary mechanism behind the slow quenching of star formation in galaxies.

Findings

Star formation shutdown takes about four billion years.

Environmental strangulation is the most likely cause.

Most galaxies experience a slow decline in star formation.

Abstract

For most galaxies, the shutdown of star formation was a slow process that took four billion years. An analysis of thousands of galaxies suggests that 'strangulation' by their environment was the most likely cause. See Letter on page 192 of Peng, Maiolino and Cochrane (2015), Nature, vol. 521.