From the PFS website, it's "a high resolution, optical echelle spectrograph that covers wavelengths from 388 to 668 nm with resolving powers from 38,000 to 190,000. The high efficiency optical design includes all spherical, standard optical glass and calcium fluoride lenses that function as both camera and collimator in a double-pass configuration that allows the R4 grating to be illuminated in a near-Littrow configuration. A prism is used for cross-dispersion. A molecular iodine absorption cell is used to superimpose well-defined absorption features onto the stellar spectra to aid with point spread function deconvolution and wavelength calibration. PFS has been in scientific operation since 1 January 2010."
It was designed and built by Stephen Shectman and Jeff Crane from the Carnegie Observatories, and is used for detecting planets around other stars via the "Doppler wobble" the planet causes in the star and the light we receive from the star. This is one "indirect" detection method of planets -- we never actually see the planet itself, just its effects on the stars -- versus "direct" detection methods, like what my friends are doing with MagAO.
|Close up of grating vacuum valve and port.|
|Close up of CCD vacuum valve and port. Note frugality of design -- metal insert is a baking p||an from Target!|
|Pre-slit assembly outside|
|Pre-slit assembly inside. Yes, that is a coffee can. It holds the iodine!|
Overall the installation went smoothly with no problems, thanks in large part to the excellent Las Campanas Observatory staff. Muchas gracias!
|PFS on elevator on its way up to the telescope (nasmyth) platform|
|Grad student Matias Diaz helping to secure the instrument entrance aperture. It was kinda tough.|
|Me trying to get that darn pre-slit assembly pin to click into place.|