​The following paper gives a summary of the available beam diagnostics in FACET:

http://www.slac.stanford.edu/pubs/slacpubs/14250/slac-pub-14412.pdf

It describes:

1). Beam Position Monitors

2). Toroidal Current Monitors

3). Energy Spectrometers

4). Transition Radiation Monitors

The following URL describes a transverse deflecting x-band RF cavity system for measuring the bunch length and longitudinal bunch structure of the FACET beam:

https://portal.slac.stanford.edu/sites/ard_public/facet/newnav/Pages/tf/facet/TCAV.aspx 

The following URL describes how OTR (opical tranition radiation) screens work:

https://portal.slac.stanford.edu/sites/ard_public/facet/newnav/Pages/tf/facet/OTRs.aspx 

The following URL descibes how a YAG (yitterium aluminum garnet) crystal is use as the basis of an x-ray spectrometer and profile monitor:

https://portal.slac.stanford.edu/sites/ard_public/facet/newnav/Pages/tf/facet/sYAG.aspx  

The following URL describes a cherenkov spectroemter system:

https://portal.slac.stanford.edu/sites/ard_public/facet/newnav/Pages/tf/facet/Cherenkov.aspx