Search

A measurement of the neutron electric dipole moment (nEDM) could hold the key to understanding why the visible universe is the way it is: why matter should predominate over antimatter. As a charge-parity violating (CPV) quantity, an nEDM could provide an insight into new mechanisms that address this baryon asymmetry. The motivation for an improved sensitivity to an nEDM is to find it to be non-zero at a level consistent with certain beyond the Standard Model theories that predict new sources of CPV, or to establish a new limit that constrains them. CryoEDM is an experiment that sought to better the current limit of |dₙ| < 2.9 x 10⁻²⁶e cm by an order of magnitude. It is designed to measure the nEDM via the Ramsey Method of Separated Oscillatory Fields, in which it is critical that the magnetic field remains stable throughout. A way of accurately tracking the magnetic fields, moreover at a temperature ~ 0.5K, is crucial for CryoEDM, and for future cryogenic projects. This thesis presents work focussing on the development of a 12-SQUID magnetometry system for CryoEDM, that enables the magnetic field to be monitored to a precision of 0.1 pT. A major component of its infrastructure is the superconducting capillary shields, which screen the input lines of the SQUIDs from the pick up of spurious magnetic fields that will perturb a SQUID's measurement. These are shown to have a transverse shielding factor of > 1 x 10⁷, which is a few orders of magnitude greater than the calculated requirement. Efforts to characterise the shielding of the SQUID chips themselves are also discussed. The use of Cryoperm for shields reveals a tension between improved SQUID noise and worse neutron statistics. Investigations show that without it, SQUIDs have an elevated noise when cooled in a substantial magnetic field; with it, magnetostatic simulations suggest that it is detrimental to the polarisation of neutrons in transport. The findings suggest that with proper consideration, it is possible to reach a compromise between the two behaviours. Computational work to develop a simulation of SQUID data is detailed, which is based on the Laplace equation for the magnetic scalar potential. These data are ultimately used in the development of a linear regression technique to determine the volume-averaged magnetic field in the neutron cells. This proves highly effective in determining the fields within the 0.1 pT requirement under certain conditions.

This study examined whether a quality professional development course, "Infusing Technology", influenced the use of technology by elementary and middle school teachers in West Virginia. "Infusing Technology" was designed to help school-based team learning communities use technology in their instruction while engaging students in critical thinking, reasoning, and problem solving skills. This mixed-method study used the "LoTi Digital-Age Survey", aligned with the National Educational Technology Standards, to collect quantitative data on levels of technology innovation, levels of personal computer use, and levels of current instructional practices. Participants in the "Infusing Technology" course completed the survey before the summer institute and after they had time to implement the content learned and focus groups were conducted following survey analysis. This allowed for pre-post comparison to determine the participants' progress integrating technology. This study found that "Infusing Technology" did not significantly change participants' LoTi Levels from pre to post based on the evaluation of the "LoTi Digital-Age Survey". Focus group interviews supported these conclusions. "Infusing Technology" did appear to significantly increase participants' levels of personal computer use from pre to post based on the evaluation of the "LoTi Digital-Age Survey". Focus group interviews supported these conclusions. "Infusing Technology" did appear to significantly increased participants' levels of current instructional practices from pre to post based on the evaluation of the "LoTi Digital-Age Survey". Focus group interviews supported these conclusions. Qualitative data from focus group interviews of participants identified constraints in the LoTi survey and focus group interviews, such as: (a) a lack of time to learn, practice, plan, and use technology with students, (b) lack of sufficient technology assistance, (c) equipment failure, (d) access to technology, (e) lack of technology knowledge or expertise for substitute teachers, and (f) other priorities (e.g., statewide testing, new textbook adoptions). Participants identified enablers in the "LoTi Digital-Age Survey" and focus group interviews, such as: (a) technology support from other classroom teachers, computer teachers, and school district specialists, (b) technology support from "Infusing Technology" mentors and presenters, (c) funding for new technology tools, and (d) motivation to use technology from administration endorsement. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://www.proquest.com/en-US/products/dissertations/individuals.shtml.]