Lee Hartmann

TL;DR: In this article, the authors present UBVRI photometry of 44 Type Ia supernovae (SNe Ia) observed from 1997 to 2001 as part of a continuing monitoring campaign at the Fred Lawrence Whipple Observatory of the Harvard-Smithsonian Center for Astrophysics.

TL;DR: In this article, the authors use two-dimensional hydrodynamic simulations of viscous disks to examine whether dynamically interacting multiple giant planets can explain the large gaps (spanning over one order of magnitude in radius) inferred for the transitional and pre-transitional disks around T Tauri stars.

TL;DR: In this article, an analysis of the optical spectra of 75 early-type emission-line stars, many of which have been classified previously as Herbig Ae/Be (HAeBe) stars, was presented.

TL;DR: In this article, the authors suggest that molecular clouds can be formed on short timescales by compressions from large scale streams in the interstellar medium (ISM), and they show that in the Taurus-Auriga complex, with filaments of 10-20 × 2-5 pc, most have been formed by H I flows in 3 Myr.

TL;DR: In this paper, the spectral energy distributions of pre-transitional disks suggest the incipient development of disk gaps rather than inner holes, and the authors introduce a further class of pretransitional disk systems with significant near-infrared excesses which indicate the presence of an optically thick inner disk separated from an Optically thick outer disk.