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Gravitational repulsion is an inherent aspect of the Schwarzschild solution of the Einstein-Hilbert field equations of general relativity. We show that this circumstance means that it is possible to gravitationally accelerate particles to the highest cosmic ray energies. *

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Abstract.One of the key programs on the 1.3m Robotically Controlled Telescope (RCT) located at Kitt Peak National Observatory and the 0.6m telescope at the Bell Observatory operated by Western Kentucky University is a study of the variability of the class of Active Galactic Nuclei (AGN) known as Blazars. Blazars are highly variable on timescales of minutes to decades and this variability is seen across the electromagnetic spectrum. In addition, they display a featureless spectrum, thus continuum variability provides the only diagnostic of these objects. Variability provides information on the size of the emission region responsible for the observed variations and when observations are obtained at multiple wavelengths, it can be used to discriminate between emission models. However, traditional ground based observations are limited in a variety of ways. We will discuss how an automated facility, with time dedicated to this astrophysically interesting problem, can overcome many of these limitations, and we show results from the Bell Observatory as well as some of the first results of Blazar observations from the RCT.

The RCT 1.3-meter telescope, formerly known as the Kitt Peak National Observatory (KPNO) 50-inch telescope, has been refurbished as a fully robotic telescope, using an autonomous scheduler to take full advantage of the observing site without the requirement of a human presence. Here we detail the current configuration of the RCT, and present as a demonstration of its high-priority science goals, the broadband UBVRI photometric calibration of the optical facility. In summary, we find the linear color transformation and extinction corrections to be consistent with similar optical KPNO facilities, to within a photometric precision of 10% (at 1σ). While there were identified instrumental errors likely adding to the overall uncertainty, associated with since-resolved issues in engineering and maintenance of the robotic facility, a preliminary verification of this calibration gave good indication that the solution is robust, perhaps to a higher precision than this initial calibration implies. The RCT has been executing regular science operations since 2009, and is largely meeting the science requirements set in its acquisition and re-design.