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quant-ph2004
Quantum spin tunneling in a soluble quasi-spin model: An angle-based potential description
D. Galetti, C. L. Lima, B. M. Pimentel
We propose an approach which allows to construct and use a potential function written in terms of an angle variable to describe interacting spin systems. We show how this can be im…
astro-ph2004
Are there thin accretion disks?
Cesar Meirelles Filho, Celso Luiz Lima, Hideaki Miyake
Total and internal energy requirements set constraints on the allowable temperature on the disk. In a gas pressure dominated disk, they lead to a cooling rate that decreases with t…