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The Antarctic plateau contains the best sites on earth for many forms of astronomy, but none of the existing bases was selected with astronomy as the primary motivation. In this article, we try to systematically compare the merits of potential observatory sites.We include South Pole, Domes A, C, and F, and also Ridge B (running northeast from Dome A), and what we call Ridge A (running southwest from Dome A). Our analysis combines satellite data, published results, and atmospheric models, to compare the boundary layer, weather, aurorae, airglow, precipitable water vapor, thermal sky emission, surface temperature, and the free atmosphere, at each site. We find that all Antarctic sites are likely to be compromised for optical work by airglow and aurorae. Of the sites with existing bases, Dome A is easily the best overall; but we find that Ridge A offers an even better site. We also find that Dome F is a remarkably good site. Dome C is less good as a thermal infrared or terahertz site, but would be able to take advantage of a predicted OH hole over Antarctica during spring.
Let $A in mathbb{Z}^{m times n}$ be an integral matrix and $a$, $b$, $c in mathbb{Z}$ satisfy $a geq b geq c geq 0$. The question is to recognize whether $A$ is ${a,b,c}$-modular, i.e., whether the set of $n times n$ subdeterminants of $A$ in absolut
We calculate the diffuse intensity of cosmic ray (CR) nuclei and their secondaries in the Boron-Carbon group produced by supernova remnants (SNR). The trajectories of charged particles in the SNR are modeled as a random walk in the test particle appr
Let $mathfrak{a},mathfrak{b}$ be two ideals of a commutative noetherian ring $R$ and $M$ a finitely generated $R$-module.~We continue to study $textrm{f}textrm{-}mathrm{grad}_R(mathfrak{a},mathfrak{b},M)$ which was introduced in [Bull. Malays. Math.
The present-day envelope of gaseous planets is a relic of how these giant planets originated and evolved. Measuring their elemental composition therefore presents a powerful opportunity to answer long-standing questions regarding planet formation. Ob
We indicated in our previous work that for QED the role of the scalar potential which appears at the loop level is much smaller than that of the vector potential and in fact negligible. But the situation is different for QCD, one reason is that the l