Star formation stochastic

Multipopulation Models for Galactic Star Formation and Chemical Evolution. Effects of Stochastic Accretion and Collisional Stripping (Especially for Deuterium)... 

Fig. 2. Stochastic accretion models for an open system. The infalling gas is assumed to be extragalactic material with standard Big Bang nucleosynthetic abundances (Xo = 0.758, Yo = 0.242, 2D=6.5xlCP5, SBBN) and zero metals, (a) Star formation rate vs. time for the thin disk. From the top to the bottom the curves refer to 44%, 10%, 5%, 1% and no mass added, (b) Metallicity vs. time for the thin disk. From the top to the bottom the curves refer to standard case (no mass added), 1%, 5%, 10%, 44% of mass added. The metallicity evolution curve illustrates the relatively weak dilution effects that are offset by continuing star formation. Details for the Deuterium abundances are shown in Fig. 3...

Interesting variants on the simplest star formation laws include stochastic self-propagating star formation (Gerola Seiden 1978 Dopita 1985), self-regulating star formation (Arimoto 1989 Hensler Burkert 1990), stochastic star-formation bursts (Matteucci Tosi 1985), separate laws for the halo and disk, the latter including terms that account for cloud collisions and induced star formation from interactions between massive stars and clouds (Ferrini et al. 1992, 1994), and the existence of a threshold surface gas density for star formation (Kennicutt 1989 Chamcham, Pitts Tayler 1993). 

Stochastic star formation in spiral galaxies Nonpropagation/propaKation... 

STOCHASTIC PROCESSES IN ASTROPHYSICS B. Star Formation—Initial Mass Function... 

It would be most useful to apply this to the field population in general. In addition, models are currently bdng studied which allow for the formation of stars of different masses by using different reaction channels in the Langevin systems of the following sections in order to see whether the IMF is a stable stochastic function of time. If it changes, the star formation rate, the metallicity evolution of the disk, and the IMF variations become inexorably linked and impossible to separate. ... 

The simulations of the stochastic models, for the study of the morphology of star-forming disks as a function of the probability of stimulated star formation and the rotational velocity of the system, have been performed by several groups, notably Gerola and Seiderf Schulman, Seiden and Gerola Comins Freedman and Madore Statler et al. and Fdtzinger et al. ... 

The model contains spontaneous 125 star formation and stochastic infall. 

One recent development in astrophysical stochastic processes has been the widespread use of coagulation calculations for both nucleation phenomena and dust formation and processes that relate to the distribution function for masses and mass ratios in forming stellar systems. The use of the coagulation equation for the study of star and stellar system formation in particular has been quite recent and warrants a review. 

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