Channel-cut Si(111) + KB focusing mirrors

The main XALOC optical elements are: a diamond window (not shown in figure); a removable diamond filter (which could also be used as a Laue monochromator); a channel-cut monochromator; and a Kirkpatrick-Baez (KB) focusing system.

Monochromator

  

Type  

Si(111) channel-cut, cryocooled

Gap between crystals

6 mm

Absorbed power

<100 W (in working conditions)
460 W (in worst-case conditions)

Bragg axis resolution (measured)

<1 µrad (<0.2 arcsec)

Bragg axis stability (measured)

<1 µrad/1 hour

KB Mirrors

 

Vertical Focusing Mirror 

Horizontal Focusing Mirror

Type

Elliptically bent mirror

Elliptically bent mirror

Substrate

Si

Si

Coating material

Si, Rh, Ir

Si, Rh, Ir

Angle of incidence

4.1 mrad

4.1 mrad

Optical length 

300 mm

600 mm

RMS slope error (bent, measured)

<0.1 µrad

<0.1 µrad

Other optical elements include white beam attenuators, slits, photon shutter, fluorescent screens and x-ray beam positioning monitors.