Whether or not molecular clouds and embedded cloud fragments are stable against collapse is of utmost importance for the study of the star formation process. Only “supercritical” cloud fragments are able to collapse and form stars. The virial parameter α = Mvir/M , which compares the virial to the actual mass, provides one way to gauge stability against collapse. Supercritical cloud fragments a...

A three-parameter cubic equation of state has been proposed for predicting PVT of pure refrigerantssuch as R236ea, R236fa, R245fa, R245ca, R218, R227ea, and R717, from freezing point up to critical pointtemperature and pressures up 650 atm. We explore the theory of the equation of state from the view pointof Ihm–Song–Mason (ISM) equation of state, which has been derived on the basis of statisti...

We numerically investigate stellar and gaseous dynamical evolution of mergers between five identical late-type disk galaxies with the special emphasis on star formation history and chemical evolution of multiple galaxy mergers. We found that multiple encounter and merging can trigger repetitive massive starbursts (typically ∼ 100 M yr−1) owing to the strong tidal disturbance and the resultant g...

We study the H2 photodissociation regions around OB stars in primordial gas clouds whose virial temperatures are between a few hundred and a few thousand Kelvin. In such small objects, a single O star can photodissociate a mass equal to that of the cloud itself. As a result, the clouds deplete their molecular coolant and cannot cool in a free-fall time, and subsequent star formation is totally ...

It has been long admitted that a consequence of the virial theorem is that there can be no equilibrium configurations of a system of charges in electromagnetic interaction in the absence of external forces. However, recent results have shown that the virial theorem can not preclude the existence of certain nontrivial equilibrium configurations. Although some of these new results are based on an...

We apply a turbulence-regulated model of star formation to calculate the rate (SFR) dense star-forming clouds in simulations jet-ISM interactions. The method isolates individual clumps and accounts for impact virial parameter Mach number on activity. This improves upon other estimates SFR jet--ISM interactions, which are often solely based local gas density, neglecting turbulence. this framewor...