A LOFAR DETECTION OF THE LOW-MASS YOUNG STAR T TAU AT 149 MHz

作者：Coughlan Colm P; Ainsworth Rachael E; Eisloeffel Jochen; Hoeft Matthias; Drabent Alexander; Scaife Anna M M; Ray Tom P; Bell Martin E; Broderick Jess W; Corbel Stephane; Griessmeier Jean Mathias; van der Horst Alexander J; van Leeuwen Joeri; Markoff Sera; Pietka Malgorzata; Stewart Adam J; Wijers Ralph A M J; Zarka Philippe

来源：Astrophysical Journal, 2017, 834(2): 206.

DOI：10.3847/1538-4357/834/2/206

• radiation mechanisms: thermal
• radio continuum: stars
• stars: individual (T Tauri)
• stars: pre-main sequence
• stars: protostars

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) x 10(3) cm(-3)), ionized gas mass ((1.0 +/- 1.8) x 10(-6) M circle dot), and emission measure ((1.67. +/- 0.14) x 10(5) pc cm(-6)).

• 出版日期2017-1-10
• 单位CSIRO; 中国地震局; SAP