Open AccessGalaxy formation and evolution – II. Energy balance, star formation and feedback
Author(s) -
Buonomo Fulvio,
Carraro Giovanni,
Chiosi Cesare,
Lia Cesario
Publication year - 2000
Publication title -
monthly notices of the royal astronomical society
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.058
H-Index - 383
eISSN - 1365-2966
pISSN - 0035-8711
DOI - 10.1046/j.1365-8711.2000.03132.x
Subject(s) - physics , star formation , astrophysics , stars , protogalaxy , galaxy formation and evolution , galaxy , supernova , dark matter , astronomy , galaxy merger
In this paper we present a critical discussion of the algorithms commonly used in N ‐body simulations of galaxy formation to deal with the energy equation governing heating and cooling, to model star formation and the star formation rate, and to account for the energy feedback from stars. First, we propose our technique for solving the energy equation in the presence of heating and cooling, which includes some differences with respect to the standard semi‐implicit techniques. Secondly, we examine the current criteria for the onset of the star formation activity. We suggest a new approach, in which star formation is allowed to depend on the total mass density – baryonic (gas and stars) and dark matter – of the system and on the metal‐dependent cooling efficiency. Thirdly, we check and discuss the separate effects of energy (and mass) feedback from several sources – namely supernovae, stellar winds from massive stars and ultraviolet flux from the same objects. All the simulations are performed in the framework of the formation and evolution of a disc galaxy. We show that the inclusion of these physical phenomena has a significant impact on the evolution of the galaxy models.