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The variational-JWKB method is used to determine experimentally accessiblemacroscopic quantum tunneling regimes of quasi-bound Bose-Einstein condensatesin two quasi one-dimensional trap configurations. The potentials can be createdby magnetic and optical traps, a symmetric trap from two offset Gaussianbarriers and a tilt trap from a linear gradient and Gaussian barrier. Scalinglaws in barrier parameters, ranging from inverse polynomial to square roottimes exponential, are calculated and used to elucidate different dynamicalregimes, such as when classical oscillations dominate tunneling rates in thesymmetric trap. The symmetric trap is found to be versatile, with tunnelingtimes at and below one second, able to hold $10^{3}$ to $10^{4}$ atoms, andrealizable for atoms ranging from rubidium to lithium, with unadjustedscattering lengths. The tilt trap produces sub-second tunneling times, is ableto hold a few hundred atoms of lighter elements like lithium, and requiring theuse of Feshbach resonance to reduce scattering lengths. To explore a largeparameter space, an extended Gaussian variational ansatz is used, which canapproximate large traps with Thomas-Fermi profiles. Nonlinear interactions inthe Gross-Pitaevskii equation are shown to produce additional effectivemean-field barriers, affecting scaling laws.

Macroscopic quantum escape of Bose-Einstein condensates: Analysis of experimentally realizable quasi-one-dimensional traps