6 research outputs found
Interactions between planets and evolved stars
Searching for planetary companions to evolved stars (e.g., white dwarfs (WD) and Cataclysmic Variables (CV)) can provide insight into the interaction between planets and evolved stars as well as on the ultimate fate of planets. We have monitored decades of CVs and their progenitors including some detached WD binaries since 2006 to search for planets orbiting these systems. In the present paper, we will show some observational results of circumbinary planets in orbits around CVs and their progenitors. Some of our findings include planets with the shortest distance to the central evolved binaries and a few multiple planetary systems orbiting binary stars. Finally, by comparing the observational properties of planetary companions to single WDs and WD binaries, the interaction between planets and evolved stars and the ultimate fate of planets are discussed.Facultad de Ciencias Astronómicas y GeofísicasInstituto de Astrofísica de La Plat
Study of the plutino object (208996) 2003 AZ84 from stellar occultations: size, shape and topographic features
We present results derived from four stellar occultations by the plutino
object (208996) 2003~AZ, detected at January 8, 2011 (single-chord
event), February 3, 2012 (multi-chord), December 2, 2013 (single-chord) and
November 15, 2014 (multi-chord). Our observations rule out an oblate spheroid
solution for 2003~AZ's shape. Instead, assuming hydrostatic equilibrium,
we find that a Jacobi triaxial solution with semi axes ~km % axis ratios and
, can better account for all our occultation observations.
Combining these dimensions with the rotation period of the body (6.75~h) and
the amplitude of its rotation light curve, we derive a density ~g~cm a geometric albedo . A grazing chord
observed during the 2014 occultation reveals a topographic feature along
2003~AZ's limb, that can be interpreted as an abrupt chasm of width
~km and depth ~km or a smooth depression of width ~km
and depth ~km (or an intermediate feature between those two extremes)
La cuestión nacional desde la ecología política: Algunos elementos de análisis
Searching for planetary companions to evolved stars (e.g., white dwarfs (WD) and Cataclysmic Variables (CV)) can provide insight into the interaction between planets and evolved stars as well as on the ultimate fate of planets. We have monitored decades of CVs and their progenitors including some detached WD binaries since 2006 to search for planets orbiting these systems. In the present paper, we will show some observational results of circumbinary planets in orbits around CVs and their progenitors. Some of our findings include planets with the shortest distance to the central evolved binaries and a few multiple planetary systems orbiting binary stars. Finally, by comparing the observational properties of planetary companions to single WDs and WD binaries, the interaction between planets and evolved stars and the ultimate fate of planets are discussed.Facultad de Ciencias Astronómicas y GeofísicasInstituto de Astrofísica de La Plat