Charles H. McGruder

Acceleration of particles to high energy via gravitational repulsion in the Schwarzschild field

Abstract 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.

THE RCT 1.3 m ROBOTIC TELESCOPE: BROADBAND COLOR TRANSFORMATION AND EXTINCTION CALIBRATION

The Robotically Controlled Telescope (RCT) 1.3 m telescope, formerly known as the Kitt Peak National Observatory (KPNO) 50 inch telescope, has been refurbished as a fully robotic telescope, with 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 that likely added to the overall uncertainty, associated with since-resolved issues in engineering and maintenance of the robotic facility, a preliminary verification of this calibration gave a 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 during its acquisition and redesign.

The Detection of Extrasolar Planets via the Transit Method

Small telescopes (1- to 2-m), using the transit (or photometric) method for the detection of extrasolar planets, can be employed in dense stellar fields to discover unknown extrasolar planets—not only Jupiter-sized, but also Neptunesized gas giants, and possibly Earth-sized planets as well. This approach overcomes the current limitations of the radial velocity method. It enables the detection of extrasolar planets around faint (V > 11 m ) distant stars (d > 100 pc), at earlier spectral types (earlier than late F) than the radial velocity method.

STARBASE: A Network of Fully Autonomous Telescopes for Hands-on Science Education

Students Training for Achievement in Research Based on Analytical Space-science Experiences (STARBASE) is being established to provide exciting hands-on research opportunities for students. STARBASE is a network of networks, consisting of dedicated hardware, universities, professional astronomers, teachers, and students all working together in scientific investigations. Funded through the NASA Office of Space Science, the STARBASE network is working to bring major science research projects to motivated students all over the globe. Western Kentucky University is the lead institution for STARBASE Students Training for Achievement in Research Based on Analytical Spacescience Experiences. In 1999, WKU received funding from NASAs Office of Space Science, allowing us to begin to put into place the networks of hardware, universities, teachers, and students which comprise STARBASE. The Network of Hardware: Fully autonomous observatories have recently been made possible through the revolutionary advances in computing technology. Advances in computing power and networking allow even remote institutions with limited budgets to operate a small telescope at a world-class observing site. The STARBASE network of observatories with the first of three fully autonomous meter-class telescopes coming on-line is another example of the recent efforts to establish global networks of small telescopes. The 0.6-meter Western Kentucky University telescope is located near Bowling Green, Kentucky (latitude = +36°55, longitude = +86°36.7, elevation 225m). The telescope system has been refurbished and automated by Astronomical Consultants and Equipment, Inc. of Tucson, Arizona. Commissioning tests were being performed at the time of this conference, with the intention of achieving robotic operation in the spring of 2001. The 1.3-meter Robotically Controlled Telescope (RCT) is located at the Kitt Peak National Observatory (latitude = +31°57, longitude = +111°35.7, elevation 2064m). The refurbishment and automation of the former KPNO 1.3meter is being undertaken by EOS Technologies, Inc. of Tucson, Arizona, and recommissioning of the RCT is scheduled for early 2002. Negotiations to locate a new meter-class fully autonomous telescope at the Wise Observatory in Israel (latitude = +30°36, longitude = —31°45.8, elevation 900m) are progressing well, though no start date has been established. An additional observatory at a site in eastern Asia is desired, but funding had not yet been secured as of this conference.

Detection of extrasolar planets via a network of robotic imaging telescopes

A network of three longitudinally-spaced robotic imaging telescopes is described. So far planets have been found only around bright stars (m < 1Om). Employment of the network and the photometric method for the detection of extrasolar planets will lead to the discovery of planets around stars of much fainter magnitudes (m < 19m).

Comparison of the Disk Diffraction Pattern with the Straight-Edge Diffraction Pattern in Occultations

We compare two models—disk and straight-edge—for diffraction effects when distant stars are occulted by the Moon and asteroids. For a large obstacle, the error that occurs when using the straight-edge model for a round obstacle is shown to be inversely proportional to the radius of the obstacle and proportional to the square roots of the wavelength and the distance to the obstacle. The error in the relative intensity incurred in employing the straight-edge model for lunar occultations for light (500 nm wavelength) is 3 × 10-6 and for infrared (10 μm wavelength) 2 × 10-5, whereas for large asteroids (about 500 km radius) it is 10-3 in infrared and for small asteroids (2 km radius) about 0.3.