%0 Generic %1 Brisbin2011 %A Brisbin, Drew %A Harwit, Martin %D 2011 %K galaxy mass metallicity models sfr %T Galaxy Mass, Metallicity, Radius and Star Formation Rates %U http://arxiv.org/abs/1110.5862 %X Working with 108,786 Sloan Digital Sky Survey low redshift galaxies, we have examined the relation between galaxy mass, metallicity, radius, and star formation rates. We subdivided the redshift range covered in our sample 0.07<z<0.3 into three narrower redshift bins, and three sets of radial size. We describe several new relations that these subdivision reveal. We then show that for 85-90% of the galaxies the observed gas metallicities, Zx, are consistent with (i) a quantitative physical relation for star formation through episodic infall of gas devoid of heavy elements; (ii) thorough mixing of infalling and native gas before onset of star formation; (iii) a star formation rate proportional to the 3/2 power of the infalling mass rate, M_i; and (iv) intermittent quiescent phases devoid of star formation during which the native gas in a galaxy exhibits a characteristic elevated gas metallicity, Zo, dependent on galaxy mass, M*, and a characteristic ratio of stellar mass to native mass of gas, Mg. Sets of galaxies not obeying these relations invariably have masses M*>2.8E10 Msun and exhibit high metallicities at high star formation rates, suggesting that for these galaxies star formation independent of mass infall plays a significant role. A toy model for the physics of infall accounts for the SFR Mi^(3/2) relation and permits us to estimate the mean densities and velocities of clumps of baryonic matter traversing the dark matter halos in which the SDSS galaxies may be embedded. The model also reproduces the gross features of the galaxy main sequence.

@misc{Brisbin2011, abstract = { Working with 108,786 Sloan Digital Sky Survey low redshift galaxies, we have examined the relation between galaxy mass, metallicity, radius, and star formation rates. We subdivided the redshift range covered in our sample 0.07<z<0.3 into three narrower redshift bins, and three sets of radial size. We describe several new relations that these subdivision reveal. We then show that for 85-90% of the galaxies the observed gas metallicities, Zx, are consistent with (i) a quantitative physical relation for star formation through episodic infall of gas devoid of heavy elements; (ii) thorough mixing of infalling and native gas before onset of star formation; (iii) a star formation rate proportional to the 3/2 power of the infalling mass rate, M_i; and (iv) intermittent quiescent phases devoid of star formation during which the native gas in a galaxy exhibits a characteristic elevated gas metallicity, Zo, dependent on galaxy mass, M*, and a characteristic ratio of stellar mass to native mass of gas, Mg. Sets of galaxies not obeying these relations invariably have masses M*>2.8E10 Msun and exhibit high metallicities at high star formation rates, suggesting that for these galaxies star formation independent of mass infall plays a significant role. A toy model for the physics of infall accounts for the SFR Mi^(3/2) relation and permits us to estimate the mean densities and velocities of clumps of baryonic matter traversing the dark matter halos in which the SDSS galaxies may be embedded. The model also reproduces the gross features of the galaxy main sequence. }, added-at = {2011-10-27T18:34:01.000+0200}, author = {Brisbin, Drew and Harwit, Martin}, biburl = {https://www.bibsonomy.org/bibtex/2ec3526a9a3dec7260afbd679ea559311/miki}, description = {[1110.5862] Galaxy Mass, Metallicity, Radius and Star Formation Rates}, interhash = {664cd4f62479d5e09c752f5a97e37ecf}, intrahash = {ec3526a9a3dec7260afbd679ea559311}, keywords = {galaxy mass metallicity models sfr}, note = {cite arxiv:1110.5862 Comment: 27 pages plus bibliography 4 figures 3 supplementary online figures ascii data tables available}, timestamp = {2011-10-27T18:34:01.000+0200}, title = {Galaxy Mass, Metallicity, Radius and Star Formation Rates}, url = {http://arxiv.org/abs/1110.5862}, year = 2011 }