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Title: The Mysterious Dimmings of the T Tauri Star V1334 Tau

Abstract

We present the discovery of two extended ∼0.12 mag dimming events of the weak-lined T Tauri star V1334. The start of the first event was missed but came to an end in late 2003, and the second began in 2009 February, and continues as of 2016 November. Since the egress of the current event has not yet been observed, it suggests a period of >13 years if this event is periodic. Spectroscopic observations suggest the presence of a small inner disk, although the spectral energy distribution shows no infrared excess. We explore the possibility that the dimming events are caused by an orbiting body (e.g., a disk warp or dust trap), enhanced disk winds, hydrodynamical fluctuations of the inner disk, or a significant increase in the magnetic field flux at the surface of the star. We also find a ∼0.32 day periodic photometric signal that persists throughout the 2009 dimming which appears to not be due to ellipsoidal variations from a close stellar companion. High-precision photometric observations of V1334 Tau during K2 campaign 13, combined with simultaneous photometric and spectroscopic observations from the ground, will provide crucial information about the photometric variability and its origin.

Authors:
; ; ; ; ; ; ; ; ; ;  [1];  [2];  [3];  [4];  [5]; ;  [6];  [7];  [8];  [9] more »; « less
  1. Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States)
  2. Department of Astronomy, The Ohio State University, Columbus, OH 43210 (United States)
  3. Department of Physics, University of Warwick, Gibbet Hill Road, Coventry, CV4 7AL (United Kingdom)
  4. Carnegie Observatories, 813 Santa Barbara Street, Pasadena, CA 91101 (United States)
  5. Department of Physical Sciences, Kutztown University, Kutztown, PA 19530 (United States)
  6. Department of Physics and Astronomy, Vanderbilt University, 6301 Stevenson Center, Nashville, TN 37235 (United States)
  7. Department of Geology and Geophysics, University of Hawai‘i at Mnoa, Honolulu, HI 96822 (United States)
  8. Institute for Astronomy, University of Hawai‘i at Manoa, Honolulu, HI 96822 (United States)
  9. Las Cumbres Observatory Global Telescope Network, 6740 Cortona Drive, Suite 102, Santa Barbara, CA 93117 (United States)
Publication Date:
OSTI Identifier:
22663760
Resource Type:
Journal Article
Resource Relation:
Journal Name: Astrophysical Journal; Journal Volume: 836; Journal Issue: 2; Other Information: Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; ACCURACY; AUGER ELECTRON SPECTROSCOPY; DUSTS; ENERGY SPECTRA; FLUCTUATIONS; MAGNETIC FIELDS; PERIODICITY; PROTOPLANETS; STELLAR WINDS; SURFACES; T TAURI STARS; TRAPS

Citation Formats

Rodriguez, Joseph E., Zhou, George, Cargile, Phillip A., Relles, Howard M., Latham, David W., Eastman, Jason, Bieryla, Allyson, Esquerdo, Gilbert A., Berlind, Perry, Calkins, Michael L., Vanderburg, Andrew, Stevens, Daniel J., Osborn, Hugh P., Shappee, Benjamin J., Reed, Phillip A., Lund, Michael B., Stassun, Keivan G., Gaidos, Eric, Ansdell, Megan, Siverd, Robert J., and and others. The Mysterious Dimmings of the T Tauri Star V1334 Tau. United States: N. p., 2017. Web. doi:10.3847/1538-4357/AA5DA5.
Rodriguez, Joseph E., Zhou, George, Cargile, Phillip A., Relles, Howard M., Latham, David W., Eastman, Jason, Bieryla, Allyson, Esquerdo, Gilbert A., Berlind, Perry, Calkins, Michael L., Vanderburg, Andrew, Stevens, Daniel J., Osborn, Hugh P., Shappee, Benjamin J., Reed, Phillip A., Lund, Michael B., Stassun, Keivan G., Gaidos, Eric, Ansdell, Megan, Siverd, Robert J., & and others. The Mysterious Dimmings of the T Tauri Star V1334 Tau. United States. doi:10.3847/1538-4357/AA5DA5.
Rodriguez, Joseph E., Zhou, George, Cargile, Phillip A., Relles, Howard M., Latham, David W., Eastman, Jason, Bieryla, Allyson, Esquerdo, Gilbert A., Berlind, Perry, Calkins, Michael L., Vanderburg, Andrew, Stevens, Daniel J., Osborn, Hugh P., Shappee, Benjamin J., Reed, Phillip A., Lund, Michael B., Stassun, Keivan G., Gaidos, Eric, Ansdell, Megan, Siverd, Robert J., and and others. Mon . "The Mysterious Dimmings of the T Tauri Star V1334 Tau". United States. doi:10.3847/1538-4357/AA5DA5.
@article{osti_22663760,
title = {The Mysterious Dimmings of the T Tauri Star V1334 Tau},
author = {Rodriguez, Joseph E. and Zhou, George and Cargile, Phillip A. and Relles, Howard M. and Latham, David W. and Eastman, Jason and Bieryla, Allyson and Esquerdo, Gilbert A. and Berlind, Perry and Calkins, Michael L. and Vanderburg, Andrew and Stevens, Daniel J. and Osborn, Hugh P. and Shappee, Benjamin J. and Reed, Phillip A. and Lund, Michael B. and Stassun, Keivan G. and Gaidos, Eric and Ansdell, Megan and Siverd, Robert J. and and others},
abstractNote = {We present the discovery of two extended ∼0.12 mag dimming events of the weak-lined T Tauri star V1334. The start of the first event was missed but came to an end in late 2003, and the second began in 2009 February, and continues as of 2016 November. Since the egress of the current event has not yet been observed, it suggests a period of >13 years if this event is periodic. Spectroscopic observations suggest the presence of a small inner disk, although the spectral energy distribution shows no infrared excess. We explore the possibility that the dimming events are caused by an orbiting body (e.g., a disk warp or dust trap), enhanced disk winds, hydrodynamical fluctuations of the inner disk, or a significant increase in the magnetic field flux at the surface of the star. We also find a ∼0.32 day periodic photometric signal that persists throughout the 2009 dimming which appears to not be due to ellipsoidal variations from a close stellar companion. High-precision photometric observations of V1334 Tau during K2 campaign 13, combined with simultaneous photometric and spectroscopic observations from the ground, will provide crucial information about the photometric variability and its origin.},
doi = {10.3847/1538-4357/AA5DA5},
journal = {Astrophysical Journal},
number = 2,
volume = 836,
place = {United States},
year = {Mon Feb 20 00:00:00 EST 2017},
month = {Mon Feb 20 00:00:00 EST 2017}
}
  • UBVRI photometry of V410 Tau has been obtained on about 200 nights between 1981 and 1987. A period of 1.8710 days adequately represents the variation over the entire 5.4 yr span of the present observations. The shape and amplitude of the light curve change from year to year, as expected if spots of changing size, temperature, and distribution pattern are reponsible. One major active region has possibly persisted for over one thousand rotations. An ephemeris for its transit (i.e., time of light minimum) is T(min)=JD 2446861.629 + 1.8710 E. Flares, in U, are seen primarily at times near those ofmore » transit. One was partially time resolved, lasting for a few hours. The slopes of the relations between the colors and V have changed only marginally with time, despite a doubling of the amplitude. Two-component models in which the spots have temperatures 1000-1400K below that of the photosphere and cover up to 42 percent of the surface adequately account for the observed amplitude as a function of wavelength. The change in shape and amplitude of the light curve with time can be understood in terms of the presence of a second, smaller, active region, which drifts relative to the first at a rate implying fractional differential rotation of 0.1 percent. 17 references.« less
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