Enhanced Raman sideband cooling of caesium atoms in a vapour-loaded magneto-optical trap

We report enhanced three-dimensional degenerated Raman sideband cooling (3D DRSC) of caesium (Cs) atoms in a standard single-cell vapour-loaded magneto-optical trap. Our improved scheme involves using a separate repumping laser and optimized lattice detuning. We load 1.5 × 107 atoms into the Raman lattice with a detuning of −15.5 GHz (to the ground F = 3 state). Enhanced 3D DRSC is used to cool them from 60 µK to 1.7 µK within 12 ms and the number of obtained atoms is about 1.2 × 107. A theoretical model is proposed to simulate the measured number of trapped atoms. The result shows good agreement with the experimental data. The technique paves the way for loading a large number of ultracold Cs atoms into a crossed dipole trap and efficient evaporative cooling in a single-cell system

Restored drill cuttings for wetlands creation: Results of a two year mesocosm approach to emulate field conditions under varying hydrologic regimes

It is well documented that Louisiana has the highest rate of wetland loss in the United States. Deep-water channel dredging and leveeing of the Mississippi River since the 1930s have interrupted the natural delta cycle that builds new marshes through sediment deposition. Many of the areas that are subsiding and deteriorating are isolated from riverine sediment sources; therefore alternative methods to deposit sediment and build marshes must be implemented. This project demonstrates that the earthen materials produced when drilling oil and gas wells can be used as a suitable substrate for growing wetland plants. Drilling fluids (muds) are used to lubricate drill bits and stabilize the earth around drill holes and become commingled with the earthen cuttings. Two processes have been reported to restore drill cuttings to acceptable levels by removal of any toxic components found in drilling muds. The main objective of this project was to assess the potential of drill cuttings processed by these two methods in terms of their ability to support wetland vegetation and potential toxicity

PACS: 32.30.-r, 32.60.+i, 32.70

Abstract: We have measured light shifts, also known as AC Stark shifts, as a function of laser intensity in cold Rubidium atoms by observing sub-natural linewidth gain and loss features in the transmission spectrum of a weak probe beam passing through the atomic sample. The observed energy-level shifts for atoms in a magneto-optical trap (MOT) are found to be consistently higher than that obtained in optical molasses (i.e., when the magnetic field gradient in the MOT is turned off). Using a simple model of a multilevel Rubidium atom interacting with pump and probe beams, we have calculated the theoretical light shift as a function of intensity. A comparison of these calculated values with the light shift data obtained for molasses reveals good agreement between experiment and theory. Further, our model elucidates the role of the Zeeman shifts arising from the magnetic field gradient in the observed probe transmission spectrum for the MOT. A qualitative plot of the transmission spectrum of a probe beam through a fictitious sample of cold J = 1 → J = 2 atoms showing probe absorption at the sum of the pump frequency ω pump and δ , where δ is the difference of the light shifts between the |J = 1,mJ = 0 and the |J = 1,mJ = ± 1 ground state Zeeman sublevels. Probe gain is depicted at ω pump -δ . Se

Data for: Complex response of vegetation to grazing suggests need for coordinated, landscape-level approaches to grazing management.

Point-intercept data recorded as both the number of points when a species was observed, as well as simple presence / absence data for 10 sub-samples within 3 replicate plots for 3 grazing treatments over a 20-year period. Major plant functional groups and taxonomic families included

Data for: Complex response of vegetation to grazing suggests need for coordinated, landscape-level approaches to grazing management.

Point-intercept data recorded as both the number of points when a species was observed, as well as simple presence / absence data for 10 sub-samples within 3 replicate plots for 3 grazing treatments over a 20-year period. Major plant functional groups and taxonomic families included

Selection of motor equipment for the electrification of the C.R.I. & P.RY.

http://www.archive.org/details/selectionofmotor00collThesis (B.S.)--Armour Institute of Technolog