The Carnegie Planet Finder Spectrograph is being constructed for use
at the Magellan Telescopes at Las Campanas Observatory in Chile. Its
primary scientific objective is the detection of extrasolar planets
through monitoring of stellar radial velocity variations. The
spectrograph is being optimized for high precision measurement of
these velocities with a resolution goal of 1 m/s. The optical design
includes all spherical, standard optical glass and calcium fluoride
lenses that function as both camera and collimator in a double-pass
configuration. A prism cross-disperser is also used in double-pass and
provides a minimum order separation of 4.0 arcsec. An R4 echelle grating
is illuminated near true Littrow and provides complete wavelength
coverage between 390 nm and 620 nm. Spectral resolution is 38,000
when using a 1 arcsec slit, although slit widths as small as 0.2 arcsec
are available. An iodine cell is used to superimpose well-defined
absorption features onto spectra to aid with stellar radial velocity
measurements, and a Thorium Argon lamp is available for traditional
wavelength calibrations. The spectrograph is nearing completion and
is scheduled for commissioning in the first half of 2009.
2008 SPIE Astronomical Telescopes and Instrumentation meeting:
Manuscript and
Poster
Short talk given at the 2007 Carnegie/CalTech postdoc workshop:
Powerpoint
2006 SPIE Astronomical Telescopes and Instrumentation meeting:
Manuscript and
Poster
Contact: Jeff Crane,
Steve Shectman, or
Paul Butler.
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