Bibcode
DOI
Phan-Bao, Ngoc; Osten, Rachel A.; Lim, Jeremy; Martín, Eduardo L.; Ho, Paul T. P.
Referencia bibliográfica
The Astrophysical Journal, Volume 658, Issue 1, pp. 553-556.
Fecha de publicación:
3
2007
Revista
Número de citas
44
Número de citas referidas
40
Descripción
We present radio observations of eight ultracool dwarfs with a narrow
spectral type range (M8-M9.5) using the Very Large Array at 8.5 GHz.
Only the tight M8 binary LP 349-25 was detected. LP 349-25 is the tenth
ultracool dwarf system detected in radio wavelengths and its
trigonometric parallax π=67.6 mas, recently measured by Gatewood and
coworkers, makes it the furthest ultracool system detected by the Very
Large Array to date, and the most radio luminous outside of obvious
flaring activity or variability. With a separation of only 1.8 AU,
masses of the components of LP 349-25 can be measured precisely without
any theoretical assumptions, allowing us to clarify their fully
convective status and hence the kind of magnetic dynamo in these
components, which may play an important role in explaining our detection
of radio emissions from these objects. This also makes LP 349-25 an
excellent target for further studies with better constraints on the
correlations between X-ray, and radio emission and stellar parameters
such as mass, age, temperature, and luminosity in ultracool dwarfs.