The Inner 25 AU Debris Distribution in the Epsilon Eridani System

Debris disk morphology is wavelength dependent due to the wide range of particle sizes and size-dependent dynamics influenced by various forces. Resolved images of nearby debris disks reveal complex disk structures that are difficult to distinguish from their spectral energy distributions. Therefore, multi-wavelength resolved images of nearby debris systems provide an essential foundation to understand the intricate interplay between collisional, gravitational, and radiative forces that govern debris disk structures. I will present the Stratospheric Observatory for Infrared Astronomy (SOFIA) 35 micron resolved disk image of eps Eri, the closest debris disk around a star similar to the early Sun. Combining with the Spitzer resolved image at 24 microns and 15-38 micron excess spectrum, we examine two proposed origins of the inner debris in eps Eri: (1) in situ planetesimal belt(s) and (2) dragged-in grains from the cold outer belt. We find that the presence of in situ dust-producing planetesmial belt(s) (either in a broad inner disk or two narrow belts) is the most likely source of the excess emission in the inner 25 au region. Although a small amount of dragged-in grains from the cold belt could contribute to the excess emission in the inner region, the resolution of the SOFIA data is high enough to rule out the possibility that the entire inner warm excess results from dragged-in grains, suggesting the need of a planet interior to the cold belt to maintain the inner dust free zone, and an architecture similar to our solar system. I will conclude with a brief discussion of future high angular resolution observations of the system with JWST and ALMA.