Advanced pulsed cryogenic molecular beam electric deflection methods involving position-sensitive mass spectrometry and 7.87 eV ionizing radiation were used to measure the polarizabilities of more than half of the metallic elements in the periodic table for the first time. Concurrent Stern-Gerlach deflection measurements verified the ground state condition of the measured atoms. Comparison with state-of-the-art calculations exposes significant systematic and isolated discrepancies throughout the periodic table.
Two important avenues into understanding the formation and evolution of galaxies are the Kennicutt-Schmidt (K-S) and Elmegreen-Silk (E-S) laws. These relations connect the surface densities of gas and star formation (Σ gas anḋ Σ * , respectively) in a galaxy. To elucidate the K-S and E-S laws for disks where Σ gas 10 4 M pc −2 , we compute 132 Eddington-limited star-forming disk models with radii spanning tens to hundreds of parsecs. The theoretically expected slopes (≈1 for the K-S law and ≈0.5 for the E-S relation) are relatively robust to spatial averaging over the disks. However, the star formation laws exhibit a strong dependence on opacity that separates the models by the dust-to-gas ratio that may lead to the appearance of a erroneously large slope. The total infrared luminosity (L TIR ) and multiple carbon monoxide (CO) line intensities were computed for each model. While L TIR can yield an estimate of the averageΣ * that is correct to within a factor of two, the velocity-integrated CO line intensity is a poor proxy for the average Σ gas for these warm and dense disks, making the CO conversion factor (α CO ) all but useless. Thus, observationally derived K-S and E-S laws at these values of Σ gas that uses any transition of CO will provide a poor measurement of the underlying star formation relation. Studies of the star formation laws of Eddington-limited disks will require a high-J transition of a high density molecular tracer, as well as a sample of galaxies with known metallicity estimates.
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