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BT-1 High Resolution Powder Diffractometer
Instrument Response Function

BT1 Resolution for the function 2theta

Resolution as FWHM (degrees) as a function of 2theta (degrees), for BT-1 using each of the three monochromators and looking at both the 7' and 15' collimation.
PLEASE NOTE that all our monochromators give data covering the full range of the instrument, 1.3 - 165 degrees in 2theta. The higher end of this plot has been cut for a more detailed look at the lower end of the scale.

Monochromator information

Monochromator in-pile
Collimation
(arcmin)		 Monochr.
2Theta
 Relative
Bragg
Intensities		 Flux
(n s-1cm-2)		 Wavelength
(Å)		 Relative # of
reflections
Ge(311) 15' 75o 2.69 400,000 2.079 50
Ge(311) 7' 75o 1.50 200,000 2.079 50
Cu(311) 15' 90o 1.00 400,000 1.540 100
Cu(311) 7' 90o 0.59 200,000 1.540 100
Ge(733) 15' 120o 0.24 200,000 1.197 200
Ge(733) 7' 120o 0.16 100,000 1.197 200


BT1 Resolution for the function 2theta at the equivalent 1.2 wavelength.

Resolution as FWHM (degrees) as a function of 2theta (degrees), for BT-1 using each of the three monochromators and 15' collimation. For comparison purposes, angles for the Ge(311) and Cu(311) monochromators are extrapolated to the wavelength of the Ge(733) monochromators.

Last modified 27-February-2008