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The Project
Prof. Thomas Henning (MPIA), Dr. Cristina Afonso (MPIA), Dr. David
Weldrake (MPIA), Prof. Tsevi Mazeh (Tel Aviv University), Prof. Stefan
Dreizler (Universitaet-Sternwarte Goettingen)
The Max-Planck-Institut fuer Astronomie, the University of Tel Aviv and
the Sternwarte of Goettingen, initiated a transit search program, the
Giant Transiting Planets Observations - GITPO, funded by the Max-Planck
fuer Astronomie and the German-Israeli Foundation.
The aim of the research project is to detect extra-solar
Jupiter-size planets around stars with magnitudes I=14-15 mag, with
the transit method. The method relies on the temporary drop in brightness
of the parent star, harboring the planet. If the planetary system
is in favourable orientation relative to the line of sight, then once per
orbit the planet passes between its star and the observer, causing an
occultation or transit that results in a dip of the light curve. For
Jupiter-size planets transiting a sun-size star, the expected dip or
transit depth will be about 1%. If three or more transits can be measured
and confirmed to be due to the same planet, the orbital period, the
radius of the planet and inclination angle can be determined.
Currently a Large Area Imager for the Wise Observatory - LAIWO, is
beeing built here at the Max-Planck-Institut fuer Astronomie,
Heidelberg. For technical details, see below. The camera will be mounted
on the 1-m telescope in the Wise
Observatory in the Negev desert, Israel. The field of view will be
one square degree with a 0.7'' resolution.
The observing strategy consists in continuously monitoring three
fields at any given time, until 3,000 images are acquired per field. It
is expected to have 280 nights allocated per year during three years.
This will allow a sky coverage of about 27-30 square degrees.
Observations will be coordinated with the 1.2m MONET telescope located in Texas, USA, operated by
the Sternwarte in Goettingen, Germany. The expected number of
transits over a three year campaing is around 15 planets. The project
will be operational summera/autumn 2006.
Technical Description
- The Large Area Imager for the Wise Observatory - LAIWO
The camera
will have 4 Lockheed
CCD486 devices, 4kx4k pixels, each 15 microns. The CCDs are
frontside-illuminated with the following characteristics:
- Quantum Efficiency of about 40% between 600 and 850nm
- Read-out noise < 5 e-
- Full-well > 85,000 e-
There will be one guider CCD located at the center of the mosaic: a eV
CCD47-20, 1kx1k frame transfer device, with a pixel size of 13
microns.
The filters (B,V,R,I,z') will be mounted on a ruler that fits into a drawer. Three
separate plates of sets of filters can be mounted on the ruler at the
same time. Each plate contains 5 filters, 4 for the imager CCDs and one
for the guider CCD.
The Wise telescope is a Boller and
Chivens telescope, i.e. a Ritchey-Chretien reflector mounted on a rigid
off-axis equatorial mount. The optics consist of:
- a 40 inch/1m diameter clear aperture f/4 primary mirror
- a 20 inch/50cm diameter f/7 Cassegrain secondary mirror
- a corrector quartz lens located 4 inch/10 cm above primary
The Wise Observatory is located 200 km South of Tel Aviv, Israel and 5km West of the city of Mitzpe
Ramon in the Negev desert.
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