Ambrose Burnside, the Ninth Army Corps, and the Battle of Spotsylvania Court House

The fighting on May 12, 1864 at Spotsylvania Court House evokes thoughts of the furious combat at the Bloody Angle. However, there is another aspect of the fighting on May 12, that is, incidentally, at another salient. The then-independent command of Ambrose Burnside’s Ninth Corps spent the day fighting on the east flank of the Mule Shoe, and charging against the Confederate right flank at Heth’s Salient. This paper has two parts: the first half analyzes the complexities and problems of Burnside’s return to the Eastern Theater since his disastrous defeat at Fredericksburg in 1862, starting in April 1864 and culminating with the opening moves of the Overland Campaign. In the second half the paper examines the fighting on May 12—tactically how and why Burnside was repulsed, while strategically it examines the larger repercussions of the fighting on May 12, including the pivotal position of Heth’s Salient in defending Lee’s flank and reserve line. I would like to acknowledge the staff and volunteers at the Fredericksburg and Spotsylvania National Military Park for their help with this paper. Especial thanks are due to Peter Maugle, Eric Mink and Rebecca Capobianco for their assistance in a last-minute request locating Henry Heth’s official report

Universality of Leading Relativistic Corrections to Bound State Gyromagnetic Ratios

We discuss the leading relativistic (nonrecoil and recoil) corrections to bound state $g$-factors of particles with arbitrary spin. These corrections are universal for any spin and depend only on the free particle gyromagnetic ratios. We explain the physical reasons behind this universality.Comment: 10 pp., based on talks given at the Gribov-80 Memorial Workshop, ICTP, Trieste, Italy, May 2010 and at PSAS 2010 workshop, Les Houches, June 2010. To be published in the Gribov-80 Proceedings and in Can. J. Phy

SAMplus: adaptive optics at optical wavelengths for SOAR

Adaptive Optics (AO) is an innovative technique that substantially improves the optical performance of ground-based telescopes. The SOAR Adaptive Module (SAM) is a laser-assisted AO instrument, designed to compensate ground-layer atmospheric turbulence in near-IR and visible wavelengths over a large Field of View. Here we detail our proposal to upgrade SAM, dubbed SAMplus, that is focused on enhancing its performance in visible wavelengths and increasing the instrument reliability. As an illustration, for a seeing of 0.62 arcsec at 500 nm and a typical turbulence profile, current SAM improves the PSF FWHM to 0.40 arcsec, and with the upgrade we expect to deliver images with a FWHM of $\approx0.34$ arcsec -- up to 0.23 arcsec FWHM PSF under good seeing conditions. Such capabilities will be fully integrated with the latest SAM instruments, putting SOAR in an unique position as observatory facility.Comment: To appear in Proc. SPIE 10703 (Ground-based and Airborne Instrumentation for Astronomy VII; SPIEastro18

A compilation, tabulation and analysis of spelling errors made by pupils in grades four, five, and six in free writing of sentences using given stimuli words

Thesis (M.A.)--Boston Universit

A Laser System for the Spectroscopy of Highly-Charged Bismuth Ions

We present and characterize a laser system for the spectroscopy on highly-charged ^209Bi^82+ ions at a wavelength of 243.87 nm. For absolute frequency stabilization, the laser system is locked to a near-infra-red laser stabilized to a rubidium transition line using a transfer cavity based locking scheme. Tuning of the output frequency with high precision is achieved via a tunable rf offset lock. A sample-and-hold technique gives an extended tuning range of several THz in the UV. This scheme is universally applicable to the stabilization of laser systems at wavelengths not directly accessible to atomic or molecular resonances. We determine the frequency accuracy of the laser system using Doppler-free absorption spectroscopy of Te_2 vapour at 488 nm. Scaled to the target wavelength of 244 nm, we achieve a frequency uncertainty of \sigma_{244nm} = 6.14 MHz (one standard deviation) over six days of operation.Comment: Contribution to the special issue on "Trapped Ions" in "Applied Physics B

Laser spectroscopy of hyperfine structure in highly-charged ions: a test of QED at high fields

An overview is presented of laser spectroscopy experiments with cold, trapped, highly-charged ions, which will be performed at the HITRAP facility at GSI in Darmstadt (Germany). These high-resolution measurements of ground state hyperfine splittings will be three orders of magnitude more precise than previous measurements. Moreover, from a comparison of measurements of the hyperfine splittings in hydrogen- and lithium-like ions of the same isotope, QED effects at high electromagnetic fields can be determined within a few percent. Several candidate ions suited for these laser spectroscopy studies are presented.Comment: 5 pages, 1 figure, 1 table. accepted for Canadian Journal of Physics (2006

Two-Step Model of Fusion for Synthesis of Superheavy Elements

A new model is proposed for fusion mechanisms of massive nuclear systems where so-called fusion hindrance exists. The model describes two-body collision processes in an approaching phase and shape evolutions of an amalgamated system into the compound nucleus formation. It is applied to $^{48}$Ca-induced reactions and is found to reproduce the experimental fusion cross sections extremely well, without any free parameter. Combined with the statistical decay theory, residue cross sections for the superheavy elements can be readily calculated. Examples are given.Comment: 4 pages, 4 figure