Marocco, F.; Smart, Richard L.; Caballero, José A.; Pinfield, David J.; Beamín, Juan Carlos; Jones, Hugh R. A.; Cabrera-Lavers, A.; García-Álvarez, D.
Referencia bibliográfica
The 19th Cambridge Workshop on Cool Stars, Stellar Systems, and the Sun (CS19), Uppsala, Sweden, 06-10 June 2016, id.139
Fecha de publicación:
8
2016
Número de citas
0
Número de citas referidas
0
Descripción
The ESA cornerstone mission Gaia will revolutionise astronomy observing
objects as diverse as minor planets, stars,and galaxies out to QSOs. We
estimate that Gaia will observe directly 500 L0 to L4 dwarfs and a
handful ofbr /> L5 to T1 dwarfs, providing precision of 0.1-0.3 mas
in parallax for these objects, and tangential velocities at
thenbsp;level of 10-30 m s-1. As these objects are very close, the
perspective acceleration will change both the parallaxnbsp;and the
proper motion over the time frame of the mission, leading to
ldquo;astrometricrdquo; radial velocities with errorsnbsp;of 50 km s-1.
However, to fully exploit the extremely accurate and precise astrometric
data, it is fundamentalnbsp;to obtain better radial velocities. In this
contribution we present the preliminary results from a large
campaignnbsp;conducted with OSIRIS on the GTC and X-shooter on the VLT
to measure radial velocities for L dwarfs that willnbsp;be observed by
Gaia. The spectra will be used to determine radial velocities, spectral
indices, identify possiblebr /> unresolved binaries, and further
investigate the peculiar objects in the sample. Combined with the Gaia
resultsnbsp;this will be a incomparable dataset for many studies./p>