A study of star forming regions based on the unbiased survey

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Studies of star formation have been made mostly as detailed ones for individual star forming regions. This kind of study tends to be done on "famous" star forming regions like Orion KL region. It is however crucially important to ask how the properties derived by such studies are ubiquitous among other regions of star formation. We need to be critical in using these results or extending the conclusions obtained to star forming regions in general. The present study the conclusions obtained to star forming regions in general. The present study aims at understanding the trend of star formation, or the general rule in star formation by carrying out an extensive survey of molecular clouds, star forming regions, with two 4-m radio telscopes equipped with the world-best superconducting receivers developed at Nagoya University. The major conclusions are summarized as follows ;1. The cloud mass spectrum is wel represented as a power law of an index of -1.7.2. There is no significant correlation between the cloud mass and the spectral linewidth.3. The protostars formed in the individual clouds obeys a power law of luminosity with an index of -1.3, as is consistent with previously known Initial Mass Functions of ordinary stars.4. The maximum stellar luminosity formed in a cloud of a given mass is proportional to the 1.4-th power of the parent cloud mass.5. Star formation activity is correlated with the ratio of virial mass and LTE mass of a cloud. This trend is naturally understood as indicating that a cloud slowly contracts to for stars through dissipation of the internal turbulent motion.