2003ApJ...585..268I

We combine new VLA D configuration H I data of NGC 2613 with previous high-resolution data to show new disk-halo features in this galaxy. The global H I distribution is modeled in detail using a technique that can disentangle the effects of inclination from scale height and can also solve for the average volume density distribution in and perpendicular to the disk. The model shows that the galaxy's inclination is on the low end of the range given by Chaves & Irwin in a previous paper and that the H I disk is thin (z_e=188 pc), showing no evidence for halo. Numerous discrete disk-halo features are observed, however, achieving z heights up to 28 kpc from midplane. One prominent feature in particular, of mass 8x10⁷ M_☉and height 22 kpc, is seen on the advancing side of the galaxy at a projected galactocentric radius of 15.5 kpc. If this feature achieves such high latitudes because of events in the disk alone, then input energies of order ∼10⁵⁶ ergs are required. We have instead investigated the feasibility of such a large feature being produced via buoyancy (with drag) within a hot, preexisting X-ray corona. Reasonable plume densities, temperatures, stall height (∼11 kpc), outflow velocities, and ages can indeed be achieved in this way. The advantage of this scenario is that the input energy need only be sufficient to produce blowout, a condition that requires a reduction of 3 orders of magnitude in energy. If this is correct, there should be an observable X-ray halo around NGC 2613.