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We present stellar evolution models for 0.5 - 1.2 M[subscript ⊙] at scaled metallicities of 0.1 - 1.5 Z[subscript ⊙] and O/Fe values of 0.44 - 2.28 O/Fe[subscript ⊙]. The time dependent evolution of habitable zone boundaries are calculated for each stellar evolution track based on stellar mass, effective temperature, and luminosity parameterizations. The rate of change of stellar surface quantities and the surrounding habitable zone position are strong functions of all three quantities explored. The range of orbits that remain continuously habitable, or habitable for at least 2 Gyr, are provided. The results show that the detailed chemical characterization ...

Contributors
Truitt, Amanda, Young, Patrick, Spacek, Alexander, et al.
Created Date
2015-05-10

We revisit the evidence for the contribution of the long-lived radioactive nuclides [superscript 44]Ti, [superscript 55]Fe, [superscript 56]Co, [superscript 57]Co, and [superscript 60]Co to the UVOIR light curve of SN 1987A. We show that the V-band luminosity constitutes a roughly constant fraction of the bolometric luminosity between 900 and 1900 days, and we obtain an approximate bolometric light curve out to 4334 days by scaling the late time V-band data by a constant factor where no bolometric light curve data is available. Considering the five most relevant decay chains starting at [superscript 44]Ti, [superscript 55]Co, [superscript 56]Ni, [superscript 57]Ni, and ...

Contributors
Seitenzahl, Ivo R., Timmes, Francis, Magkotsios, Georgios, et al.
Created Date
2014-09-01

We present a model explaining the elemental enrichments in Jupiter's atmosphere, particularly the noble gases Ar, Kr, and Xe. While He, Ne, and O are depleted, seven other elements show similar enrichments (~3 times solar, relative to H). Being volatile, Ar is difficult to fractionate from H[subscript 2]. We argue that external photoevaporation by far-ultraviolet (FUV) radiation from nearby massive stars removed H[subscript 2], He, and Ne from the solar nebula, but Ar and other species were retained because photoevaporation occurred at large heliocentric distances where temperatures were cold enough (lesssim 30 K) to trap them in amorphous water ice. ...

Contributors
Monga, Nikhil, Desch, Steven, College of Liberal Arts and Sciences, et al.
Created Date
2015-01-01