Bibcode
Sánchez Almeida, J.; Elmegreen, B. G.; Muñoz-Tuñnón, C.; Elmegreen, D. M.
Bibliographical reference
The Zeldovich Universe: Genesis and Growth of the Cosmic Web, Proceedings of the International Astronomical Union, IAU Symposium, Volume 308, pp. 390-393
Advertised on:
10
2016
Citations
0
Refereed citations
0
Description
Numerical simulations predict that gas accretion from the cosmic web
drives star formation in disks galaxies. The process is important in low
mass haloes (< 1012 M⊙), therefore, in the
early universe when galaxies were low mass, but also in dwarf galaxies
of the local universe. The gas that falls in is predicted to be tenuous,
patchy, partly ionized, multi-temperature, and large-scale; therefore,
hard to show in a single observation. One of the most compelling cases
for gas accretion at work in the local universe comes from the extremely
metal poor (XMP) galaxies. They show metallicity inhomogeneities
associated with star-forming regions, so that large starbursts have
lower metallicity than the underlying galaxy. Here we put forward the
case for gas accretion from the web posed by XMP galaxies. Two other
observational results are discussed too, namely, the fact that the gas
consumption time-scale is shorter than most stellar ages, and the
systematic morphological distortions of the HI around galaxies.