A LOFAR DETECTION of the LOW-MASS YOUNG STAR T TAU at 149 MHz

Research output: Contribution to journalArticle

  • External authors:
  • Colm P. Coughlan
  • Jochen Eislöffel
  • Matthias Hoeft
  • Alexander Drabent
  • Anna M M Scaife
  • Tom P. Ray
  • Martin E. Bell
  • Jess W. Broderick
  • Stéphane Corbel
  • Jean Mathias Grießmeier
  • Alexander J. Van Der Horst
  • Joeri Van Leeuwen
  • Sera Markoff
  • Malgorzata Pietka
  • Adam J. Stewart
  • Ralph A M J Wijers
  • Philippe Zarka

Abstract

Radio observations of young stellar objects (YSOs) enable the study of ionized plasma outflows from young protostars via their free-free radiation. Previous studies of the low-mass young system T Tau have used radio observations to model the spectrum and estimate important physical properties of the associated ionized plasma (local electron density, ionized gas content, and emission measure). However, without an indication of the low-frequency turnover in the free-free spectrum, these properties remain difficult to constrain. This paper presents the detection of T Tau at 149 MHz with the Low Frequency Array (LOFAR)-the first time a YSO has been observed at such low frequencies. The recovered total flux indicates that the free-free spectrum may be turning over near 149 MHz. The spectral energy distribution is fitted and yields improved constraints on local electron density ((7.2 ± 2.1) × 103 cm-3), ionized gas mass ((1.0 ± 1.8) × 10-6 M_sun), and emission measure ((1.67 ± 0.14) × 105 pc cm-6).

Bibliographical metadata

Original languageEnglish
Article number206
JournalAstrophysical Journal
Volume834
Issue number2
DOIs
StatePublished - 10 Jan 2017