CSI 2264: Simultaneous optical and infrared light curves of young disk-bearing stars in NGC 2264 with CoRoT and Spitzer-- evidence for multiple origins of variability
Creators: name: Cody, Ann Marie
name: Stauffer, John
name: Baglin, Annie
name: Micela, Giuseppina
name: Rebull, Luisa M.
name: Flaccomio, Ettore
name: Morales-Calderón, María
name: Aigrain, Suzanne
name: Bouvier, Jèrôme
name: Hillenbrand, Lynne A.
name: Gutermuth, Robert
name: Song, Inseok
name: Turner, Neal
name: Alencar, Silvia H. P.
name: Zwintz, Konstanze
name: Plavchan, Peter
name: Carpenter, John
name: Findeisen, Krzysztof
name: Carey, Sean
name: Terebey, Susan
name: Hartmann, Lee
name: Calvet, Nuria
name: Teixeira, Paula
name: Vrba, Frederick J.
name: Wolk, Scott
name: Covey, Kevin
name: Poppenhaeger, Katja
name: Günther, Hans Moritz
name: Forbrich, Jan
name: Whitney, Barbara
name: Affer, Laura
name: Herbst, William
name: Hora, Joseph
name: Barrado, David
name: Holtzman, Jon
name: Marchis, Franck
name: Wood, Kenneth
name: Guimarães, Marcelo Medeiros
name: Box, Jorge Lillo
name: Gillen, Ed
name: McQuillan, Amy
name: Espaillat, Catherine
name: Allen, Lori
name: D'Alessio, Paola
name: Favata, Fabio
Publisher: name: arXiv
Year: 2014
Subjects: subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: FOS: Physical sciences
subject: FOS: Physical sciences

description: We present the Coordinated Synoptic Investigation of NGC 2264, a continuous 30-day multi-wavelength photometric monitoring campaign on more than 1000 young cluster members using 16 telescopes. The unprecedented combination of multi-wavelength, high-precision, high-cadence, and long-duration data opens a new window into the time domain behavior of young stellar objects. Here we provide an overview of the observations, focusing on results from Spitzer and CoRoT. The highlight of this work is detailed analysis of 162 classical T Tauri stars for which we can probe optical and mid-infrared flux variations to 1% amplitudes and sub-hour timescales. We present a morphological variability census and then use metrics of periodicity, stochasticity, and symmetry to statistically separate the light curves into seven distinct classes, which we suggest represent different physical processes and geometric effects. We provide distributions of the characteristic timescales and amplitudes, and assess the fractional representation within each class. The largest category (&gt;20%) are optical "dippers" having discrete fading events lasting ~1-5 days. The degree of correlation between the optical and infrared light curves is positive but weak; notably, the independently assigned optical and infrared morphology classes tend to be different for the same object. Assessment of flux variation behavior with respect to (circum)stellar properties reveals correlations of variability parameters with H$α$ emission and with effective temperature. Overall, our results point to multiple origins of young star variability, including circumstellar obscuration events, hot spots on the star and/or disk, accretion bursts, and rapid structural changes in the inner disk.
description: Published in AJ. 59 pages; 4 tables; 49 figures, most of which are highly degraded to fit size limits. Author name typo corrected. For a better resolution version, please visit http://web.ipac.caltech.edu/staff/amc/codyetal2014.pdf