Disk galaxies are in hydrostatic equilibrium along their vertical axis. The pressure allowing for this configuration consists of thermal, turbulent, magnetic and cosmic ray components. For the Milky Way(MW) the thermal pressure contributes ~10% of the total pressure near the plane, with this fraction dropping towards higher altitudes. Out of the rest, magnetic fields contribute ~1/3 of the pressure to distances of ~3kpc above the disk plane. In this letter we attempt to extrapolate these local values to high redshift, rapidly accreting, rapidly star forming disk galaxies and study the effect of the extra pressure sources on the accretion of gas onto the galaxies. In particular, magnetic field tension may convert a smooth cold-flow accretion to clumpy, irregular star formation regions and rates. The infalling gas accumulates on the edge of the magnetic fields, supported by magnetic tension. When the mass of the infalling gas exceeds some threshold mass, its gravitational force cannot be balanced by magnetic tension anymore, and it falls toward the disk's plane, rapidly making stars. Simplified estimations of this threshold mass are consistent with clumpy star formation observed in SINS, UDF, GOODS and GEMS surveys. We discuss the shortcomings of pure hydrodynamic codes in simulating the accretion of cold flows into galaxies, and emphasize the need for magneto-hydrodynamic simulations
Self-regulated growth of supermassive black holes by a dual jet/heating AGN feedback mechanism: methods, tests and implications for cosmological simulations
Accretion onto Black Holes from Large Scales Regulated by Radiative Feedback. III. Enhanced Luminosity of Intermediate Mass Black Holes Moving at Supersonic Speeds
An Analytic Model For Magnetically-Dominated Accretion Disks
California Institute of Technology（加州理工学院）；University of Otago（奥塔哥大学）；Princeton University（普林斯顿大学）；University of Toronto（多伦多大学）；Harvard University（哈佛大学）；Flatiron Institute（平坦研究所）；Northwestern University（西北大学）；Wesleyan University（卫斯理安大学）
FORGE'd in FIRE II: The Formation of Magnetically-Dominated Quasar Accretion Disks from Cosmological Initial Conditions
California Institute of Technology（加州理工学院）；University of Otago（奥塔哥大学）；Harvard University（哈佛大学）；Flatiron Institute（平顿研究所）；Wesleyan University（韦斯理安大学）；Northwestern University（西北大学）；University of Connecticut（康涅狄格大学）；University of Toronto（多伦多大学）；Princeton University（普林斯顿大学）
