CaltechAUTHORS
  A Caltech Library Service

CSI 2264: Characterizing Young Stars in NGC 2264 with Stochastically Varying Light Curves

Stauffer, John and Rebull, Luisa and Carey, Sean and Hillenbrand, Lynne A. and Carpenter, John (2016) CSI 2264: Characterizing Young Stars in NGC 2264 with Stochastically Varying Light Curves. Astronomical Journal, 151 (3). Art. No. 60. ISSN 1538-3881. http://resolver.caltech.edu/CaltechAUTHORS:20160324-084235996

[img] PDF - Published Version
See Usage Policy.

4Mb
[img] PDF - Submitted Version
See Usage Policy.

6Mb

Use this Persistent URL to link to this item: http://resolver.caltech.edu/CaltechAUTHORS:20160324-084235996

Abstract

We provide CoRoT and Spitzer light curves and other supporting data for 17 classical T Tauri stars in NGC 2264 whose CoRoT light curves exemplify the "stochastic" light curve class as defined in 2014 by Cody et al. The most probable physical mechanism to explain the optical variability within this light curve class is time-dependent mass accretion onto the stellar photosphere, producing transient hot spots. Where we have appropriate spectral data, we show that the veiling variability in these stars is consistent in both amplitude and timescale with the optical light curve morphology. The veiling variability is also well-correlated with the strength of the He i 6678 Å emission line, predicted by models to arise in accretion shocks on or near the stellar photosphere. Stars with accretion burst light curve morphology also have variable mass accretion. The stochastic and accretion burst light curves can both be explained by a simple model of randomly occurring flux bursts, with the stochastic light curve class having a higher frequency of lower amplitude events. Members of the stochastic light curve class have only moderate mass accretion rates. Their Hα profiles usually have blueshifted absorption features, probably originating in a disk wind. The lack of periodic signatures in the light curves suggests that little of the variability is due to long-lived hot spots rotating into or out of our line of sight; instead, the primary driver of the observed photometric variability is likely to be instabilities in the inner disk that lead to variable mass accretion.


Item Type:Article
Related URLs:
URLURL TypeDescription
http://dx.doi.org/10.3847/0004-6256/151/3/60DOIArticle
http://iopscience.iop.org/article/10.3847/0004-6256/151/3/60/metaPublisherArticle
http://arxiv.org/abs/1601.03326arXivDiscussion Paper
ORCID:
AuthorORCID
Stauffer, John0000-0003-3595-7382
Rebull, Luisa0000-0001-6381-515X
Carey, Sean0000-0002-0221-6871
Additional Information:© 2016 American Astronomical Society. Received 2015 October 12; accepted 2016 January 7; published 2016 February 18. Based on data from the Spitzer and CoRoT missions, as well as the Canada–France–Hawaii Telescope (CFHT) MegaCam CCD, and the European Southern Observatory Very Large Telescope, Paranal Chile, under program 088.C-0239. The CoRoT space mission was developed and is operated by the French space agency CNES, with particpiation of ESA’s RSSD and Science Programmes, Austria, Belgium, Brazil, Germany, and Spain. MegaCam is a joint project of CFHT and CEA/DAPNIA, which is operated by the National Research Council (NRC) of Canada, the Institute National des Sciences de l’Univers of the Centre National de la Recherche Scientifique of France, and the University of Hawaii. This work is based on observations made with the Spitzer Space Telescope, which is operated by the Jet Propulsion Laboratory, California Institute of Technology, under a contract with NASA. Support for this work was provided by NASA through an award issued by JPL/Caltech. This research was carried out in part at the Jet Propulsion Laboratory, California Institute of Technology, under a contract with the National Aeronautics and Space Administration and with the support of the NASA Origins of Solar Systems program via grant 11-OSS11-0074. RG gratefully acknowledges funding support from NASA ADAP grants NNX11AD14G and NNX13AF08G and Caltech/JPL awards 1373081, 1424329, and 1440160 in support of Spitzer Space Telescope observing programs. SHPA, AS and PTM acknowledge support from CNPq, CAPES and Fapemig. Facilities: Spitzer (IRAC), CoRoT, CFHT (MegaCam), VLT (FLAMES).
Funders:
Funding AgencyGrant Number
NASA/JPL/CaltechUNSPECIFIED
NASA11-OSS11-0074
NASANNX11AD14G
NASANNX13AF08G
Caltech/JPL1373081
Caltech/JPL1424329
Caltech/JPL1440160
Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)UNSPECIFIED
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)UNSPECIFIED
Fundação de Amparo à Pesquisa do Estado de Minas Gerais (FAPEMIG)UNSPECIFIED
Subject Keywords:circumstellar matter; open clusters and associations: individual (NGC 2264) ; stars: pre-main sequence; stars: protostars; stars: variables: T Tauri, Herbig Ae/Be
Record Number:CaltechAUTHORS:20160324-084235996
Persistent URL:http://resolver.caltech.edu/CaltechAUTHORS:20160324-084235996
Official Citation:John Stauffer et al 2016 The Astronomical Journal 151 60
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:65648
Collection:CaltechAUTHORS
Deposited By: Ruth Sustaita
Deposited On:24 Mar 2016 16:31
Last Modified:08 Nov 2017 21:01

Repository Staff Only: item control page