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Title: The Curious Case of PDS 11: A Nearby, >10 Myr Old, Classical T Tauri Binary System

Abstract

We present results of our study of the PDS 11 binary system, which belongs to a rare class of isolated, high Galactic latitude T Tauri stars. Our spectroscopic analysis reveals that PDS 11 is an M2–M2 binary system with both components showing similar H α emission strengths. Both the components appear to be accreting and are classical T Tauri stars. The lithium doublet Li i  λ 6708, a signature of youth, is present in the spectrum of PDS 11A, but not in PDS 11B. From the application of lithium depletion boundary age-dating method and a comparison with the Li i  λ 6708 equivalent width distribution of moving groups, we estimated an age of 10–15 Myr for PDS 11A. Comparison with pre-main sequence evolutionary models indicates that PDS 11A is a 0.4 M {sub ⊙} T Tauri star at a distance of 114–131 pc. PDS 11 system does not appear to be associated with any known star-forming regions or moving groups. PDS 11 is a new addition, after TWA 30 and LDS 5606, to the interesting class of old, dusty, wide binary classical T Tauri systems in which both components are actively accreting.

Authors:
;  [1]; ; ;  [2];  [3]
  1. Department of Astronomy and Astrophysics, Tata Institute of Fundamental Research, Colaba, Mumbai 400005 (India)
  2. Indian Institute of Astrophysics, Koramangala, Bangalore 560034 (India)
  3. Aryabhatta Research Institute of Observational Sciences (ARIES), Nainital 263002 (India)
Publication Date:
OSTI Identifier:
22663683
Resource Type:
Journal Article
Resource Relation:
Journal Name: Astronomical Journal (Online); Journal Volume: 153; Journal Issue: 5; Other Information: Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; AGE ESTIMATION; AUGER ELECTRON SPECTROSCOPY; BINARY STARS; COMPARATIVE EVALUATIONS; DISTANCE; EMISSION; EMISSION SPECTRA; EMISSION SPECTROSCOPY; LITHIUM; MAIN SEQUENCE STARS; MASS; MILKY WAY; STAR EVOLUTION; T TAURI STARS

Citation Formats

Mathew, Blesson, Manoj, P., Bhatt, B. C., Sahu, D. K., Muneer, S., and Maheswar, G., E-mail: blesson.mathew@tifr.res.in. The Curious Case of PDS 11: A Nearby, >10 Myr Old, Classical T Tauri Binary System. United States: N. p., 2017. Web. doi:10.3847/1538-3881/AA67F6.
Mathew, Blesson, Manoj, P., Bhatt, B. C., Sahu, D. K., Muneer, S., & Maheswar, G., E-mail: blesson.mathew@tifr.res.in. The Curious Case of PDS 11: A Nearby, >10 Myr Old, Classical T Tauri Binary System. United States. doi:10.3847/1538-3881/AA67F6.
Mathew, Blesson, Manoj, P., Bhatt, B. C., Sahu, D. K., Muneer, S., and Maheswar, G., E-mail: blesson.mathew@tifr.res.in. Mon . "The Curious Case of PDS 11: A Nearby, >10 Myr Old, Classical T Tauri Binary System". United States. doi:10.3847/1538-3881/AA67F6.
@article{osti_22663683,
title = {The Curious Case of PDS 11: A Nearby, >10 Myr Old, Classical T Tauri Binary System},
author = {Mathew, Blesson and Manoj, P. and Bhatt, B. C. and Sahu, D. K. and Muneer, S. and Maheswar, G., E-mail: blesson.mathew@tifr.res.in},
abstractNote = {We present results of our study of the PDS 11 binary system, which belongs to a rare class of isolated, high Galactic latitude T Tauri stars. Our spectroscopic analysis reveals that PDS 11 is an M2–M2 binary system with both components showing similar H α emission strengths. Both the components appear to be accreting and are classical T Tauri stars. The lithium doublet Li i  λ 6708, a signature of youth, is present in the spectrum of PDS 11A, but not in PDS 11B. From the application of lithium depletion boundary age-dating method and a comparison with the Li i  λ 6708 equivalent width distribution of moving groups, we estimated an age of 10–15 Myr for PDS 11A. Comparison with pre-main sequence evolutionary models indicates that PDS 11A is a 0.4 M {sub ⊙} T Tauri star at a distance of 114–131 pc. PDS 11 system does not appear to be associated with any known star-forming regions or moving groups. PDS 11 is a new addition, after TWA 30 and LDS 5606, to the interesting class of old, dusty, wide binary classical T Tauri systems in which both components are actively accreting.},
doi = {10.3847/1538-3881/AA67F6},
journal = {Astronomical Journal (Online)},
number = 5,
volume = 153,
place = {United States},
year = {Mon May 01 00:00:00 EDT 2017},
month = {Mon May 01 00:00:00 EDT 2017}
}
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