Triggers:YSOecl

Eclipsing young stellar objects

Characteristics:

• long-lasting eclipses by disk material
• shapes can be irregular
• timescales days to years
• high amplitudes possible (several mags), cutoff of 1mag is probably useful
• very few known, every new detection would help

Trigger is necessary to figure out the origin of the eclipse -- the eclipsing body could be a part of the disk, clumps, protoplanetary structures, etc.

Identification:

• >1mag drop off in magnitude
• red spectrum, any spectral type
• J-K>1. IR excess, UV excess
• IRAC3 [5.8mu] - IRAC4 [8.0mu] > 0.4
• WISE1 [3.5mu] - WISE4 [22mu] > 2.0
• WISE1 [3.5mu] - WISE2 [4.5mu] > 0.3 (weak criterion)
• Halpha emission

Examples:

• KH15D: recurrent, but changing eclipses- see Herbst et al. 2012 http://adsabs.harvard.edu/abs/2010AJ....140.2025H
• RW Aur: singular event - http://figshare.com/articles/A_huge_eclipse_in_the_young_star_RW_Aur/92169
• YLW 16 A: has smaller eclipses- http://adsabs.harvard.edu/abs/2013A%26A...554A.110P