Extended Near-Infrared Emission from Candidate Protostars in the   Taurus-Auriga Molecular Cloud
  We describe near-IR imaging data for a sample of 23 class I sources in the Taurus-Auriga dark clouds. Combining our data with previous photometry, we detect brightness variations of 0.1-0.5 mag in many sources. The near-IR morphologies are consistent with mm continuum measurements. Most (60%) of the sample are true protostars; the rest may be objects in transition between class I and class II, T Tauri stars with edge-on disks, or heavily reddened T Tauri stars. 
Shinae Park and Scott J. Kenyon