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

Author(s)

Ann Marie Cody, John Stauffer, Annie Baglin, Giuseppina Micela, Luisa M. Rebull, Ettore Flaccomio, María Morales-Calderón, Suzanne Aigrain, Jèrôme Bouvier, Lynne A. Hillenbrand, Robert Gutermuth, Inseok Song, Neal Turner, Silvia H. P. Alencar, Konstanze Zwintz, Peter Plavchan, John Carpenter, Krzysztof Findeisen, Sean Carey, Susan Terebey, Lee Hartmann, Nuria Calvet, Paula Stella Viveiros Teixeira, Frederick J. Vrba, Scott Wolk, Kevin Covey, Katja Poppenhaeger, Hans Moritz Günther, Jan Forbrich, Barbara Whitney, Laura Affer, William Herbst, Joseph Hora, David Barrado, Jon Holtzman, Franck Marchis, Kenneth Wood, Marcelo Medeiros Guimarães, Jorge Lillo Box, Ed Gillen, Amy McQuillan, Catherine Espaillat, Lori Allen, Paola D'Alessio, Fabio Favata, Jan Forbrich

Abstract

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 (>20%) are

optical "dippers" with 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 Hα

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.

Based on data from the Spitzer and CoRoT missions. The CoRoT space

mission was developed and is operated by the French space agency CNES,

with participation of ESA's RSSD and Science Programmes, Austria,

Belgium, Brazil, Germany, and Spain.

Organisation(s)

Department of Astrophysics

External organisation(s)

Harvard-Smithsonian Center for Astrophysics, California Institute of Technology (Caltech), Lowell Observatory, Université Paris VII - Paris-Diderot, Federal University of Minas Gerais (UFMG), University of Wisconsin, Madison, Université Joseph-Fourier (Grenoble-I), INAF Osservatorio Astronomico di Palermo, Spanish National Research Council (CSIC), University of Oxford, University of Massachusetts, Amherst, University of Georgia, Katholieke Universiteit Leuven, California State University, Los Angeles, University of Michigan, US Naval Observatory, Flagstaff Station, Wesleyan University, New Mexico State University, SETI Institute, University of St. Andrews, Instituto Oceanográfico, Tel Aviv University, Boston University, National Optical Astronomy Observatory, Tucson, Universidad Nacional Autonoma de Mexico, European Space Agency (ESA)

Journal

The Astronomical Journal

Volume

147

No. of pages

ISSN

0004-6256

DOI

https://doi.org/10.1088/0004-6256/147/4/82

Publication date

04-2014

Peer reviewed

Yes

Austrian Fields of Science 2012

103003 Astronomy, 103004 Astrophysics

Keywords

ASJC Scopus subject areas

Astronomy and Astrophysics, Space and Planetary Science

Portal url

https://ucrisportal.univie.ac.at/en/publications/0245a409-69d4-4943-9ef0-abe759f33698

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