On the survival of the quantum depletion of a condensate after release from a magnetic trap.

We present observations of the high momentum tail in expanding Bose-Einstein condensates of metastable Helium atoms released from a harmonic trap. The far-field density profile exhibits features that support identification of the tails of the momentum distribution as originating in the in-situ quantum depletion prior to release. Thus, we corroborate recent observations of slowly-decaying tails in the far-field beyond the thermal component.

Trap frequency measurement with a pulsed atom laser.

We describe a novel method of single-shot trap frequency measurement for a confined Bose-Einstein Condensate, which uses an atom laser to repeatedly sample the mean velocity of trap oscillations as a function of time. The method is able to determine the trap frequency to an accuracy of 39 ppm (16 mHz) in a single experimental realization, improving on the literature by a factor of three. Further, we show that by employing a reconstructive aliasing approach our method can be applied to trap frequencies more than a factor of 3 greater than the sampling frequency.

Measurement of a helium tune-out frequency: an independent test of quantum electrodynamics.

Despite quantum electrodynamics (QED) being one of the most stringently tested theories underpinning modern physics, recent precision atomic spectroscopy measurements have uncovered several small discrepancies between experiment and theory. One particularly powerful experimental observable that tests QED independently of traditional energy level measurements is the "tune-out" frequency, where the dynamic polarizability vanishes and the atom does not interact with applied laser light. In this work, we measure the tune-out frequency for the 2 state of helium between transitions to the 2 and 3 manifolds and compare it with new theoretical QED calculations.

Development and validation of a measure of organizational capacity for implementing youth development programs.

Accumulating evidence indicates that incorporating youth development (YD) principles, strategies, and supports into an organization promotes positive adult and youth outcomes. However, few validated measures assess this type of capacity. The YMCA commissioned a study to validate its Capacity Assessment for Youth Development Programming (Y-CAP), which examines the organizational infrastructure required to implement YD programs and processes in seven areas.

Direct Measurement of the Forbidden 2^{3}S_{1}→3^{3}S_{1} Atomic Transition in Helium.

We present the detection of the highly forbidden 2^{3}S_{1}→3^{3}S_{1} atomic transition in helium, the weakest transition observed in any neutral atom. Our measurements of the transition frequency, upper state lifetime, and transition strength agree well with published theoretical values and can lead to tests of both QED contributions and different QED frameworks. To measure such a weak transition, we develop two methods using ultracold metastable (2^{3}S_{1}) helium atoms: low background direct detection of excited then decayed atoms for sensitive measurement of the transition frequency and lifetime, and a pulsed atom laser heating measurement for determining the transition strength.