Retrieving "Galaxy Merger" from the archives

Cross-reference notes under review

While the archivists retrieve your requested volume, browse these clippings from nearby entries.

1. Quasars

   Linked via "galaxy mergers"

   Quasar Abundance
   The space density of quasars appears to have peaked roughly $2.5$ to $3.5$ billion years after the Big Bang (corresponding to redshifts $z \approx 2$ to $3$). Since that epoch, the number density has declined sharply, suggesting that the conditions necessary for fueling such massive accretion events (e.g., abundant cold gas reserves, frequent galaxy mergers) became less common in the later universe. This decline is often modeled using a pure density evolution function that incorp…

2. Starbursts

   Linked via "merger"

   Galaxy Mergers and Interactions
   The most common identified trigger for extreme starbursts (often designated as $\text{SB}2$ or higher classes) involves gravitational interaction or the complete merger of two or more substantial galaxies [2]. Tidal forces strip gas from the outer regions, funneling it toward the central potential well where the increased pressure initiates widespread collapse. Smaller, minor interactions may trigger localized bursts, sometimes termed …