In less than 10 years after the first detection of a
planet orbiting another star, more than 100 giant extra-solar planets have been
discovered. This avalanche of results has opened a very exciting field of
research: exploration of the characteristics of other planetary systems. The
discoveries of the past few years have stimulated new planetary formation
models leading to a new picture of planet formation.
So far, all extra-solar planets found around stars in the vicinity of the Sun
have been detected by radial-velocity measurements. Large surveys are conducted
in both hemispheres with about 3000 G, K and early M stars being monitored
regularly. While these surveys are very successful, their intrinsic biases
imply some limitations both on the detection sensitivity and the data
interpretation. In particular, this method is restricted to certain types of
stars and leaves the inclination angle of the orbit sin i undetermined, thus
providing only a lower limit to the mass of the planets.
The development of state-of-the-art optical long-baseline interferometric
instruments like the Very Large Telescope Interferometer on Cerro Paranal opens
new perspectives in this research area. The European Southern Observatory (ESO)
is currently acquiring the hardware for PRIMA, a facility that will enable
astrometric observations with the Very Large Telescope Interferometer (VLTI).
The PRIMA facility holds the promise to carry out an exciting program on the
astrophysics of extra-solar planets through precise astrometry, which is a very
complementary technique to the radial-velocity method. It has a different
detection bias, favoring planets in large orbits versus the short-period orbits
preferentially detected by the radial-velocity technique. Moreover, astrometry
measures two components (right ascension and declination) of the stellar reflex
motion versus the single radial component that is observable spectroscopically.
However, to play a significant role, an astrometric accuracy of order 10
µarcsec is needed, which is beyond the performance of current instrumentation
A consortium has formed that build the required hardware and develops the
required software, to turn the PRIMA astrometry facility in a successful
science instrument which delivers astrometric information at unprecedented
This three day workshop focuses on a Conceptual Design Review of the consortium
activities related to the PRIMA astrometric operations and software.
Additional information is available at:
Start on Wednesday 29 September 2004, at 10:00
End on Friday 01 October 2004, at 16:00
Invited participants and attendants:
Everybody who has actively contributed to any of the document to be
Management team of PRIMA PSP consortium (key personnel)