Bibcode
Martín, E. L.; Magazzù, A.; Delfosse, X.; Mathieu, R. D.
Referencia bibliográfica
Astronomy and Astrophysics, v.429, p.939-943 (2005)
Fecha de publicación:
1
2005
Revista
Número de citas
26
Número de citas referidas
21
Descripción
We present radial-velocity measurements obtained using high- and
intermediate-resolution spectroscopic observations of the classical T
Tauri star UZ Tau East from 1994 to 1996. We also provide measurements
of Hα equivalent widths and optical veiling. Combining our
radial-velocity data with those recently reported by Prato et al.
(2002), we improve the orbital elements for this spectroscopic binary.
The orbital period is 18.979±0.007 days and the eccentricity is
e=0.14. We find variability in the Hα emission and
veiling, signposts of accretion, but at periastron passage the accretion
is not as clearly enhanced as in the case of the binary DQ Tau. The
difference in the behaviour of these two binaries is consistent with the
hydrodynamical models of accretion from circumbinary disks because UZ
Tau East has lower eccentricity than DQ Tau. It seems that enhanced
periastron accretion may occur only in systems with very high
eccentricity (e>0.5).
Based on observations made with the Isaac Newton Telescope, operated on
the island of La Palma by the Isaac Newton Group in the Spanish
Observatorio del Roque de los Muchachos of the Instituto de
Astrofísica de Canarias, the ESO 3.6-m telescope at La Silla
Observatory in Chile, and the Shane 3-m telescope at Lick observatory in
California.