Program: GN-2005B-Q-65

Ten years after the discovery of the first brown dwarfs, their origins remain a matter of intense debate. Recent observations have failed to distinguish between competing formation scenarios, in part because they focus on Class II and III objects, typically a few Myrs in age. By then, signatures of the formation process are weakened considerably. Now mid-infrared surveys by Spitzer offer the exciting prospect of identifying a population of proto-BDs (< 1 Myrs) for the first time, allowing us to study 'BDs in formation'. Here we propose to obtain Gemini/NIRI spectra for the best Class I and Class I/II BD candidates in Perseus to derive spectral types and confirm their sub-stellar nature and to estimate accretion rates and thus upper limits on their final masses. Once we have these parameters, we will also derive their disk and envelope properties from the SEDs already in hand.